The first observations of intracellular structures that probably represented mitochondria were published in the 1840s. Richard Altmann, in 1890, established them as cell organelles and called them "bioblasts". The term "mitochondria" was coined by Carl Benda in 1898. Leonor Michaelis discovered that Janus green can be used as a supravital stain for mitochondria in 1900. In 1904, Friedrich Meves, made the first recorded observation of mitochondria in plants in cells of the white waterlily, "Nymphaea alba" and in 1908, along with Claudius Regaud, suggested that they contain proteins and lipids. Benjamin F. Kingsbury, in 1912, first related them with cell respiration, but almost exclusively based on morphological observations.
History of discovery and research
Mitochondrion
Mitochondrion | History of discovery and research
1890. 1890 1890. 1890
the mitochrondria is the powerhouse of the cell
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Yes.
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who was the first to discover it?
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Richard Altmann.
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what exactly is it?
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It is a semi autonomous double-membrane-bound organelle found in most eukaryotic organisms.
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who is the above-mentioned person?
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A German pathologist and histologist.
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when did he discover this organelle mentioned above?
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The first observations of intracellular structures that probably represented mitochondria were published in the 1840s. Richard Altmann, in 1890, established them as cell organelles and called them "bioblasts". The term "mitochondria" was coined by Carl Benda in 1898. Leonor Michaelis discovered that Janus green can be used as a supravital stain for mitochondria in 1900. In 1904, Friedrich Meves, made the first recorded observation of mitochondria in plants in cells of the white waterlily, "Nymphaea alba" and in 1908, along with Claudius Regaud, suggested that they contain proteins and lipids. Benjamin F. Kingsbury, in 1912, first related them with cell respiration, but almost exclusively based on morphological observations.
Mitochondrion | History of discovery and research
The first high-resolution electron micrographs appeared in 1952, replacing the Janus Green stains as the preferred way of visualizing the mitochondria. This led to a more detailed analysis of the structure of the mitochondria, including confirmation that they were surrounded by a membrane. It also showed a second membrane inside the mitochondria that folded up in ridges dividing up the inner chamber and that the size and shape of the mitochondria varied from cell to cell.
Mitochondrion | History of discovery and research
However, most scientists disputed his discovery as nothing but a staining artefact. Their microscopes were not powerful enough to identify the organelles. By the 1930s, Golgi's description was largely rejected. It was only firmly established after 50 years of its discovery, when electron microscopes were developed.
Camillo Golgi | Cell organelle
It was later determined that the lateral border Kent was referring to was in fact the oral aperture of "Trimastix", which also contained a fourth flagella . Today, the morphology of "Trimastix" is better understood, including details not initially observed by Kent, such as Trimastix lacking a conventional mitochondrion. Current research indicates that despite there being no strong evidence that the organelle can produce ATP, there are many mitochondrial functions that it appears to have maintained .
Trimastix | History of Knowledge
In the following years, the mechanism behind cellular respiration was further elaborated, although its link to the mitochondria was not known. The introduction of tissue fractionation by Albert Claude allowed mitochondria to be isolated from other cell fractions and biochemical analysis to be conducted on them alone. In 1946, he concluded that cytochrome oxidase and other enzymes responsible for the respiratory chain were isolated to the mitochondria. Eugene Kennedy and Albert Lehninger discovered in 1948 that mitochondria are the site of oxidative phosphorylation in eukaryotes. Over time, the fractionation method was further developed, improving the quality of the mitochondria isolated, and other elements of cell respiration were determined to occur in the mitochondria.
Mitochondrion | History of discovery and research
The nucleus was the first organelle to be discovered. What is most likely the oldest preserved drawing dates back to the early microscopist Antonie van Leeuwenhoek (1632–1723). He observed a "lumen", the nucleus, in the red blood cells of salmon. Unlike mammalian red blood cells, those of other vertebrates still contain nuclei. The nucleus was also described by Franz Bauer in 1804 and in more detail in 1831 by Scottish botanist Robert Brown in a talk at the Linnean Society of London. Brown was studying orchids under the microscope when he observed an opaque area, which he called the "areola" or "nucleus", in the cells of the flower's outer layer.
Cell nucleus | History
De Duve was skeptical of referring to the new-found enzymes as microbodies because, as he noted, "too little is known of their enzyme complement and of their role in the physiology of the liver cells to substantiate a proposal at the present time". He suggested that these enzymes belonged to the same cell organelle, but one different from previously known organelles. But, as strong evidences were still lacking, he did not publish his hypothesis. In 1955 his team demonstrated similar cell fractions with same biochemical properties from the ciliated protozoan "Tetrahymena pyriformis"; thus, it was indicated that the particles were undescribed cell organelles unrelated to mitochondria.
Christian de Duve | Discovery of peroxisome
He was the first to use electron microscope to study biological cells. Earlier electron microscopes were used only in physical researches. His first electron microscopic study was on the structure of mitochondria in 1945. He was given American citizenship in 1941. He discovered that mitochondria are the "power houses" of all cells. He also discovered cytoplasmic granules full of RNA and named them "microsomes", which were later renamed ribosomes, the protein synthesizing machineries of cell. With his associate, Keith Porter, he found a "lace-work" structure that was eventually proven to be the major structural feature of the interior of all eukaryotic cells.
Albert Claude | Career
It had been suggested in the late 19th century when similarities between mitochondria and bacteria were noted, but largely dismissed until it was revived and championed by Lynn Margulis in the 1960s and 1970s; Margulis was able to make use of new evidence that such organelles had their own DNA that was inherited independently from that in the cell's nucleus.
History of evolutionary thought | Microbiology, horizontal gene transfer, and endosymbiosis
An organelle in eukaryotice cells now known as Golgi apparatus or Golgi complex, or sometimes simply as Golgi, was discovered by Camillo Golgi. Golgi modified his black reaction using osmium dichromate solution with which he stained the nerve cells (Purkinje cells) of the cerebellum of an owl. He noticed thread-like networks inside the cells and named them "apparato reticolare interno" (internal reticular apparatus). Recognising them to be unique cellular components, he presented his discovery before the Medical-Surgical Society of Pavia in April 1898. After the same was confirmed by his assistant Emilio Veratti, he published it in the "Bollettino della Società medico-chirurgica di Pavia".
Camillo Golgi | Cell organelle
Following the discovery of cellular organelles in the nineteenth century, little was known about their function and synthesis until the development of electron microscopy and subcellular fractionation in the twentieth century. This allowed experiments on the function, structure, and biogenesis of these organelles to commence. Mechanisms of protein sorting and retrieval have been found to give organelles their characteristic composition. It is known that cellular organelles can come from preexisting organelles; however, it is a subject of controversy whether organelles can be created without a preexisting one.
Organelle biogenesis | Discovery
g., mitosomes and hydrogenosomes). By this, mitochondria, hydrogenosomes, mitosomes, and related organelles as found in some loricifera (e. g. "Spinoloricus") and myxozoa (e. g. "Henneguya zschokkei") are together classified as MROs, mitochondrion-related organelles.
Mitochondrion | Origin and evolution
The mitochondrion (, plural mitochondria) is a semi autonomous double-membrane-bound organelle found in most eukaryotic organisms. Some cells in some multicellular organisms may, however, lack mitochondria (for example, mature mammalian red blood cells). A number of unicellular organisms, such as microsporidia, parabasalids, and diplomonads, have also reduced or transformed their mitochondria into other structures. To date, only one eukaryote, "Monocercomonoides", is known to have completely lost its mitochondria, and one multicellular organism, "Henneguya salminicola", is known to have retained mitochondrion-related organelles in association with a complete loss of their mitochondrial genome. The word mitochondrion comes from the Greek , , "thread", and , , "granule" or "grain-like".
Mitochondrion | Introduction
In 1913, particles from extracts of guinea-pig liver were linked to respiration by Otto Heinrich Warburg, which he called "grana". Warburg and Heinrich Otto Wieland, who had also postulated a similar particle mechanism, disagreed on the chemical nature of the respiration. It was not until 1925, when David Keilin discovered cytochromes, that the respiratory chain was described. In 1939, experiments using minced muscle cells demonstrated that cellular respiration using one oxygen atom can form two adenosine triphosphate (ATP) molecules, and, in 1941, the concept of the phosphate bonds of ATP being a form of energy in cellular metabolism was developed by Fritz Albert Lipmann.
Mitochondrion | History of discovery and research
Wallin was the first to experimentally investigate the origin of mitochondria, particularly in relation to their similarities with certain bacteria. His first paper in 1922 described the staining techniques for bacterial cells, and found that the techniques were equally good for staining mitochondria. He concluded that "bacteria and mitochondria have a similar chemical constitution". His subsequent paper (in the same year and same journal) further strengthened his assumptions. In addition, he observed in his study of blue green algae that chloroplasts are "bacteria or bacteria-like organisms that accepted the leisure of a symbiotic partnership in the struggle for existence". He made a summary conclusion that: Wallin was aware that he needed to culture mitochondria isolated from cell in an independent environment.
Ivan Wallin | Origin of mitochondria
His early experiment was a failure using tissue samples from guinea pig, dog, and human blood. However, he succeeded in obtaining a mitochondrial culture with liver of fetal and newborn rabbits. He reported his findings in 1924 with a remark that "mitochondria are, in reality, bacterial organisms, symbiotically combined with the tissues of higher organisms." He continued with prolific publications. The series of his papers titled "On the nature of mitochondria" reached nine in 1925. He gave a full description of his experiments and theories on mitochondria in his 1927 book "Symbionticism and the Origin of Species". Although he claimed that his experiments were performed with utmost care, critics rejected them on the grounds of possible contamination, and Wallin and his works were largely forgotten, until Lynn Margulis introduced a more complete endosymbiotic theory with better evidences in 1967.
Ivan Wallin | Origin of mitochondria
This innovation may have come from primitive eukaryotes capturing oxygen-powered bacteria as endosymbionts and transforming them into organelles called mitochondria. The earliest evidence of complex eukaryotes with organelles (such as mitochondria) dates from .
Paleontology | History of life
Ivan Emanuel Wallin (22 January 1883 – 6 March 1969) was an American biologist who made the first experimental works on endosymbiotic theory. Nicknamed the "Mitochondria Man", he claimed that mitochondria, which are cell organelles, were once independent bacteria, as supported by his comparative studies and culture of isolated mitochondria. From 1922, he published a series of papers titled "On the nature of mitochondria" in the "American Journal of Anatomy" which became the experimental foundations of his claims. He was the first person to specifically postulate that eukaryotic organelles originated from bacteria, and that symbiosis is a major force in creation of new species.
Ivan Wallin | Introduction
The VNO was discovered by Frederik Ruysch prior to 1732, and later by Ludwig Jacobson in 1813.
Vomeronasal organ | History
Autophagy was first observed by Keith R. Porter and his student Thomas Ashford at the Rockefeller Institute. In January 1962 they reported an increased number of lysosomes in rat liver cells after the addition of glucagon, and that some displaced lysosomes towards the centre of the cell contained other cell organelles such as mitochondria. They called this autolysis after Christian de Duve and Alex B. Novikoff. However Porter and Ashford wrongly interpreted their data as lysosome formation (ignoring the pre-existing organelles). Lysosomes could not be cell organelles, but part of cytoplasm such as mitochondria, and that hydrolytic enzymes were produced by microbodies.
Autophagy | History
He specialized in subcellular biochemistry and cell biology and discovered new cell organelles.
Christian de Duve | Career and research
Van der Giezen has published extensively in his field of research and made over 50 contributions as external seminars and lectures at international scientific meetings. Van der Giezen investigates adaptations of microbial eukaryotes to life under anoxia, or low oxygen. He discovered mitochondrial remnants (mitosomes) in the human intestinal parasite "Giardia intestinalis", an organism until then considered to be one of the most primitive eukaryotes. This discovery called for re-assessment of the evolution of mitochondria. Van der Giezen's research has demonstrated that several unusual organelles are in fact mitochondria. More recently, he has conducted large dataset analyses of microbial eukaryotes.
Mark van der Giezen | Scientific achievements
In 1903, Nikolai K. Koltsov proposed that the shape of cells was determined by a network of tubules that he termed the cytoskeleton. The concept of a protein mosaic that dynamically coordinated cytoplasmic biochemistry was proposed by Rudolph Peters in 1929 while the term ("cytosquelette", in French) was first introduced by French embryologist Paul Wintrebert in 1931. When the cytoskeleton was first introduced, it was thought to be an uninteresting gel-like substance that helped organelles stay in place. Much research took place to try to understand the purpose of the cytoskeleton and its components. With the help of Stuart Hameroff and Roger Penrose, it was discovered that microtubules vibrate within neurons in the brain, suggesting that brain waves come from deeper microtubule vibrations.
Cytoskeleton | History
Other classics include: identification of how skeletal bones grow through osteoblast deposition and osteoclast remodeling, early discovery of the biogenesis and metabolism of thyroxine and detection of triiodothyronine, early prediction of DNA semiconservative replication published days after the Watson and Crick Nature article, the discovery of axonal transport, the Warshawsky et al. finding that nascent proteins are processed from the rough endoplasmic reticulum through the Golgi apparatus into pancreatic zymogen granules (made in hot competition with the Palade lab at Rockefeller University), the first realization that the Golgi apparatus is the site of terminal glycosylation, the discovery of the cell coat, the cellular biogenesis of collagen, and new insights into the ultrastructure of basement membrane.
Charles Philippe Leblond | Other studies
He named the granules "bioblasts", and explained them as the elementary living units, having metabolic and genetic autonomy, in his 1890 book ""Die Elementarorganismen"" ("The Elementary Organism"). His explanation drew much skepticism and harsh criticism. Altmann's granules are now believed to be mitochondria.
Richard Altmann | Introduction
In 1956 Novikoff described a new class of membrane-bound organelles that he called "dense bodies." was the first to describe the actual lysosomal functions with respect to degradation of mitochondria. However he thought that the digestive activities he observed were due to other intracelluar organelles which he called "cytolysomes". It was at the "Ciba Foundation Symposium on Lysosomes" held in London on 12–14 February 1963, that he explained this phenomenon in which organelles such as endoplasmic reticulum, ribosomes, mitochondria and other cell debris were degraded by autolysis in the cytolysomes. Then the following speaker de Duve correctly identified that these organelles were lysosomes, and named them autophagic vacuoles, and he introduced the term "autophagy" for the process of such intracellular digestion.
Alex B. Novikoff | Achievements
Alternatively, Edwards (1982) proposed that the inner tissue of "Nematothallus" comprised stringy tubes, with the cellular patterning produced by their ends.
Nematothallus | History of research
Mitochondrial DNA was discovered in the 1960s by Margit M. K. Nass and Sylvan Nass by electron microscopy as DNase-sensitive threads inside mitochondria, and by Ellen Haslbrunner, Hans Tuppy and Gottfried Schatz by biochemical assays on highly purified mitochondrial fractions.
Mitochondrial DNA | History
Mitochondrial DNA was discovered by Nash and Margit in 1963. One to many double stranded mainly circular DNA is present in mitochondrial matrix. Mitochondrial DNA is 1% of total DNA of a cell. It is rich in guanine and cytosine content. Mitochondria of mammals have 55s ribosomes.
Mitochondrial matrix | Introduction
Schatz played a leading role in elucidating the biogenesis of mitochondria and in discovering mitochondrial DNA. He recognized that this DNA encoded only a small number of mitochondrial proteins which was decisive for his further research on the import of proteins into the mitochondria and the degradation of proteins within these organelles. Schatz discovered a complex transport system that recognizes mitochondrial proteins made in the cytoplasm by specific signals attached to these proteins and then transfers them into the mitochondria. This system comprises two protein complexes, TOM and TIM, which are localized in the outer and inner mitochondrial membranes respectively.
Gottfried Schatz | Work
Lewis was among the first scientists to observe the dynamics of mitochondria in living cells. In 1915 Margaret and Warren Lewis published a comprehensive analysis of the shapes and movements of mitochondria in cultured cells. Lewis's pioneering time-lapse studies included observations of mitochondrial movement toward and away from the centrosome, mitochondrial fission, and mitochondrial fusion. In the same paper, Lewis presented perhaps the first descriptions of stress-induced mitochondrial fragmentation and mitophagy.
Margaret Reed Lewis | Cell biology
Carl Benda (30 December 1857 Berlin – 24 May 1932 Turin) was one of the first microbiologists to use a microscope in studying the internal structure of cells. In an 1898 experiment using crystal violet as a specific stain, Benda first became aware of the existence of hundreds of these tiny bodies in the cytoplasm of eukaryotic cells and assumed that they reinforced the cell structure. Because of their tendency to form long chains, he coined the name "mitochondria" ("thread granules"). These bodies had first been noted in 1857 by the physiologist and pioneer of the light microscope, Albert von Kölliker, and were later termed "bioblasts" by Richard Altmann in 1886.
Carl Benda | Introduction
Owing to its large size and distinctive structure, the Golgi apparatus was one of the first organelles to be discovered and observed in detail. It was discovered in 1898 by Italian physician Camillo Golgi during an investigation of the nervous system. After first observing it under his microscope, he termed the structure as "apparato reticolare interno" ("internal reticular apparatus"). Some doubted the discovery at first, arguing that the appearance of the structure was merely an optical illusion created by the observation technique used by Golgi. With the development of modern microscopes in the twentieth century, the discovery was confirmed. Early references to the Golgi apparatus referred to it by various names including the "Golgi–Holmgren apparatus", "Golgi–Holmgren ducts", and "Golgi–Kopsch apparatus".
Golgi apparatus | Discovery
Bütschli, Schneider and Fol might have also claimed the discovery of the process presently known as "mitosis". In 1873, the German zoologist Otto Bütschli published data from observations on nematodes. A few years later, he discovered and described mitosis based on those observations.
Mitosis | Discovery
Mazia's research focused mainly on processes of mitosis , and was the first to isolate a spindle apparatus from a cell undergoing cell division. This research was done in conjunction with Katsuma Dan where they completed the first successful isolation of a mitotic apparatus from sea urchin eggs. This was a discovery that shocked the cell biology community. This discovery ended doubt of what the apparatus looked like, as well as opened a variety of new questions about the makeup of the apparatus, and how the appearance and disappearance of the structure was controlled. He never lost interest in the apparatus, and continued to research it throughout his career.
Daniel Mazia | Isolating the mitotic spindle
And, together with Daniel Mazia, he was the first to isolate the mitotic apparatus and subject it to biochemical study. This work demonstrated conclusively the existence of the mitotic spindle and initiated the modern biochemical study of mitosis.
Katsuma Dan | Introduction
In 1953, Wolfgang Zenker proved that the formation shows further development and can be found in adult humans with regularity. Since then, several studies have been performed on its comparative anatomy, histology, cytochemistry, and ultrastructural level. As soon as this structure had been shown to occur not only at all stages of human life but also in many other mammals and reptiles and since no signs of involution could be detected in any of the species investigated, it was renamed – from a topographical point of view – as "Juxtaoral organ" by Zenker and Salzer 1962. The results of the studies of Zenker and his group on this organ as well as the history of research are summarised in the monograph "Juxtaoral Organ: Morphology and Clinical aspects", Urban&Schwarzenberg 1982.
Juxtaoral organ of Chievitz | Introduction
Also in 1998, Reski and coworkers generated a knockout moss by deleting an "ftsZ" gene and thus identified the first gene essential in the division of an organelle in any eukaryote. Based on the results of further research on the ftsZ-gene family, Ralf Reski coined the term "plastoskeleton", analogous to the term "cytoskeleton", in 2000 and presented a new concept in cell biology of how chloroplasts, the green cell organelles of plants, change shape and divide.
Ralf Reski | Research
The vault or vault cytoplasmic ribonucleoprotein is a eukaryotic organelle whose function is not fully understood. Discovered and isolated by Nancy Kedersha and Leonard Rome in 1986, vaults are cytoplasmic organelles which when negative-stained and viewed under an electron microscope resemble the arches of a cathedral vaulted ceiling, with 39-fold (Or D39d) symmetry. They are present in many types of eukaryotic cells and appear to be highly conserved amongst eukaryotes.
Vault (organelle) | Introduction
In 1909, while studying chloroplast genomes, Erwin Baur made the first observations about organelle inheritance patterns. Organelle genome inheritance differs from nuclear genome, and this is illustrated by four violations of Mendel's laws.
Heteroplasmy | Organelle inheritance patterns
The first contribution of Roland Douce was the characterization of cardiolipin, the major lipid of the mitochondrial membrane of plants and animals, as phosphatidyl ethanolamine. He then considerably improved the methods of purification of chloroplasts and mitochondria, and obtained the first envelope preparations. He was the first to show that the chloroplast shell is the site of biosynthesis of galactolipids and in particular MGDG, monogalactosyldiacylglycerol. With his team, he will characterize the lipid and protein components of the envelope of the plastids. He will succeed in separating the inner and outer shells. This work will pave the way for a detailed analysis of the chloroplast, its envelopes and functions .
Roland Douce | Main discoveries
He presented his discovery at a meeting of the American Society for Cell Biology in 1955, and formally published in 1966, creating the name peroxisomes for the organelles as they are involved in peroxidase reactions. In 1968 he achieved the first large-scale preparation of peroxisomes, confirming that l-α hydroxyacid oxidase, d-amino acid oxidase, and catalase were all the unique enzymes of peroxisomes. De Duve and his team went on to show that peroxisomes play important metabolic roles, including the β-oxidation of very long-chain fatty acids by a pathway different from that in mitochondria; and that they are members of a large family of evolutionarily related organelles present in diverse cells including plants and protozoa, where they carry out distinct functions.
Christian de Duve | Discovery of peroxisome
(Thomas) Martin Embley is a Professor at Newcastle University who has made contributions to our understanding of the origin of eukaryotes and the evolution of organelles such as mitochondria, mitosomes and hydrogenosomes, that are found in parasitic protists.
Martin Embley | Introduction
Vestweber has worked in three different areas of molecular biology. During his studies for his PhD in the laboratory of Rolf Kemler he investigated the molecular mechanisms of cell recognition and cell adhesion between epithelial cells and during the development of the mouse preimplantation embryo, working on the adhesion molecule E-cadherin (uvomorulin). In the course of his postdoctoral work in the group of Gottfried Schatz at the Biocenter in Basel, Vestweber studied the biogenesis of mitochondria and found the first membrane component (today known as TOM 40) of the mitochondrial import machinery for the transport of proteins into this organelle.
Dietmar Vestweber | Research
In 1975, Carpenter discovered and published a paper on the recombination nodule, an organelle that mediates meiotic recombination.
Adelaide Carpenter | Scientific work
Both mitochondria and sorting endosomes undergo major rearrangements leading to fission where they contact the ER. Sites of close apposition can also form between most of these organelles most pairwise combinations. First mentions of these contact sites can be found in papers published in the late 1950s mainly visualized using electron microscopy (EM) techniques. Copeland and Dalton described them as “highly specialized tubular form of endoplasmic reticulum in association with the mitochondria and apparently in turn, with the vascular border of the cell”.
Membrane contact site | Introduction
Serendipity followed de Duve for another major discovery. After the confirmation of lysosome, de Duve's team was troubled by the presence (in the rat liver cell fraction) of the enzyme urate oxidase. De Duve thought it was not a lysosome because it is not an acid hydrolase, typical of lysosomal enzymes; still, it had similar distribution as the enzyme acid phosphatase. Further, in 1960 he found other enzymes (such as catalase and D-amino acid oxidase), that were similarly distributed in the cell fraction—and it was then thought that these were mitochondrial enzymes. (W. Bernhard and C. Rouillier had described such extra-mitochodrial organelles as microbodies, and believed that they were precursors to mitochondria.) de Duve noted the three enzymes exhibited similar chemical properties and were similar to those of other peroxide-producing oxidases.
Christian de Duve | Discovery of peroxisome
Of this discovery G. Cuvier published an account, "Description Anatomique d'un Organe Observé dans les Mammifères," in "Annales du Muséum d'Histoire Naturelle" (Paris, 1811). This discovery at once placed Jacobson in the front rank of the biologists of his age. The Danish society of sciences awarded him a silver medal of honor; he was given military rank as a regimental surgeon, and was granted a royal stipend to enable him to travel through Germany and France. During his sojourn in Paris Jacobson devoted a great deal of time to the study of practical medicine and surgery, and was so successful that the Danish government, on his return in 1813, obtained for him admission into the French army in order that he might study the medical system employed therein.
Ludwig Lewin Jacobson | Jacobsonian organ
The function of the nucleus remained unclear.
Cell nucleus | History
This topic stayed untouched until the 1980s. Initial evidence that DNA could move among cell compartments came when fragments of chloroplast DNA were found in the maize mitochondrial genome with the help of cross-hybridization, between chloroplast and mitochondrial DNA, and physical mapping of homologous regions. After this initial observation, Ellis coined the name "promiscuous DNA" in order to signify the transfer of DNA intracellularly from one organelle to the other and is the presence of organelle DNA in multiple cellular compartments. This is not only an important discovery on its own, but is also highly informative and helpful for understanding the evolutionary process and the time period different occurrence might take place.
NUMT | Brief History of NUMT
The ability of these bacteria to conduct respiration in host cells that had relied on glycolysis and fermentation would have provided a considerable evolutionary advantage. This symbiotic relationship probably developed 1.7 to 2 billion years ago. A few groups of unicellular eukaryotes have only vestigial mitochondria or derived structures: the microsporidians, metamonads, and archamoebae. These groups appear as the most primitive eukaryotes on phylogenetic trees constructed using rRNA information, which once suggested that they appeared before the origin of mitochondria. However, this is now known to be an artifact of long-branch attraction—they are derived groups and retain genes or organelles derived from mitochondria (e.
Mitochondrion | Origin and evolution
Perutz discovered that the detailed three-dimensional structures of proteins, such as myoglobin and hemoglobin could, in principle, be solved by X-ray analysis using a heavy metal atom labeling technique. Hugh Huxley discovered that muscle contraction works by a sliding filament mechanism.
MRC Laboratory of Molecular Biology | Origins: 1947-61
The hydrogen hypothesis is a model proposed by William F. Martin and Miklós Müller in 1998 that describes a possible way in which the mitochondrion arose as an endosymbiont within an archaeon (classified as an undoubted prokaryote at that time), giving rise to a symbiotic association of two cells from which the first eukaryotic cell could have arisen (symbiogenesis). According to the hydrogen hypothesis:
Hydrogen hypothesis | Introduction
Mesentery has been known for thousands of years, however it was unclear whether mesentery is a single organ or there are several mesenteries. The classical anatomical description of the mesocolon is credited to British surgeon Sir Frederick Treves in 1885, although a description of the membrane as a single structure dates back to at least Leonardo da Vinci. Treves is known for performing the first appendectomy in England in 1888; he was surgeon to both Queen Victoria and King Edward VII. He studied the human mesentery and peritoneal folds in 100 cadavers and described the right and left mesocolons as vestigial or absent in the human adult.
Mesentery | History
(The more related two species are, the more mtDNA/RNA mutations will be the same in their mitochondrial genome). Using these techniques, it is estimated that the first mitochondria arose around 1.5 billion years ago. A generally accepted hypothesis is that mitochondria originated as an aerobic prokaryote in a symbiotic relationship within an anaerobic eukaryote.
Human mitochondrial genetics | Genetic code variants
He discovered, in the chloroplast, an original mechanism of self-regulation of translation for certain photosynthesis proteins that are only produced if they can be assembled in a functional protein complex (CES process). Recently, he revisited the early days of endosymbiosis by showing how protein addressing signals to intracellular organelles would derive from antimicrobial peptides against which the ancestors of mitochondria and chloroplasts developed resistance.
Francis-André Wollman | Scientific work
The Rickettsiales are widely believed to be the closest relatives to mitochondria. Based on the fact that the "Midichlorian" genes for the flagellum and for the cbb3 cytochrome oxidase were proven to be ancestral, the genes were inferred to have been present in the bacterium that established the symbiosis with the ancestor of the eukaryotic cell, which became the mitochondrion. Hence, sequencing the genome of "M. mitochondrii" allowed an improved reconstruction of the mitochondrion's hypothetical free-living ancestor: It was a motile bacterium able to survive in microaerophilic conditions. Both these characteristics may have played an important role in the beginning of the symbiosis between the eukaryotic cell and the mitochondrion.
Midichloria | "Midichloria" and the origin of mitochondria
At the University of California, San Francisco, Hyman investigated the interaction between chromosomes and microtubules that create the mitotic forces that separate chromosomes in the lab of Tim Mitchison. He also created a number of tools that are used today:
Anthony A. Hyman | Research
The porosome was discovered in the early to mid-1990s by a team led by Professor Bhanu Pratap Jena at Yale University School of Medicine, using atomic force microscopy.
Porosome | History of discovery
Edouard Van Beneden made the first observation of centrosomes (which are composed of two orthogonal centrioles) in 1883. In 1895, Theodor Boveri named the organelle a "centrosome". The pattern of centriole duplication was first worked out independently by Étienne de Harven and Joseph G. Gall c. 1950.
Centriole | History
Endosymbiotic theory for the origin of mitochondria suggests that the proto-eukaryote engulfed a protomitochondria, and this endosymbiont became an organelle.
Symbiogenesis | Endosymbiosis of Protomitochondria
PTMs were first observed in 1901, when Claudius Regaud made a detailed study of the histology and physiology of the seminiferous tubules in rats. He described the PTMs as a single layer of flattened cells, which enclose the seminiferous tubules, and called them ‘’modified connective tissue cells’’. In 1958, Yves Clermont made a further investigation of the cells by electron microscopy. He found that these cells have a cytological resemblance to smooth muscle cells – they contain actin filaments, have invaginations at the cell surface and their organelles are located in the centre of the cell. He also suggested that these cells are responsible for the tubular contraction and referred to them as ‘’interlamellar cells’’.
Peritubular myoid cell | History
In 1981, Horwich moved back to New Haven, Connecticut for a postdoctoral fellowship at Yale University School of Medicine. He worked in the laboratory of Leon Rosenberg. In 1984, he moved across the hall from Rosenberg's lab to start his own laboratory as an assistant professor in the department of genetics. He still collaborated with members of the Rosenberg laboratory, including Wayne Fenton. As an independent researcher, Horwich asked whether the pathway that imports an enzyme called ornithine transcarbamylase (OTC) into the mitochondria of mammalian cells also could work in yeast. In 1987, during a genetic screen in yeast, Horwich and his colleagues stumbled across a protein folding function inside mitochondria.
Arthur L. Horwich | Research
A mitochondrion contains DNA, which is organized as several copies of a single, usually circular chromosome. This mitochondrial chromosome contains genes for redox proteins, such as those of the respiratory chain. The CoRR hypothesis proposes that this co-location is required for redox regulation. The mitochondrial genome codes for some RNAs of ribosomes, and the 22 tRNAs necessary for the translation of mRNAs into protein. The circular structure is also found in prokaryotes. The proto-mitochondrion was probably closely related to "Rickettsia". However, the exact relationship of the ancestor of mitochondria to the alphaproteobacteria and whether the mitochondrion was formed at the same time or after the nucleus, remains controversial.
Mitochondrion | Origin and evolution
Soon afterwards, he discovered gaps in sheaths of nerve fibers, which were later called the Nodes of Ranvier. This discovery later led Ranvier to careful histological examination of myelin sheaths and Schwann cells.
Node of Ranvier | History
The term was suggested in 1946 by Lwoff and collaborators.
Organotroph | History
In Gif-sur-Yvette, Bernard Dujon started to study a strange genetic phenomenon, linked to mitochondrial genetics, whose study was still in infancy. When crossing two haploid yeast species carrying different mitochondrial mutations, conferring the resistance to erythromycin or to chloramphenicol, allele segregation did not follow mendelian rules and recombinants appeared in mysterious proportions. At that time, no one had any idea of the genetic content of mitochondria, except that it contained DNA. Bernard Dujon was studying a particular mitochondrial locus, called "omega", that could be present as two different alleles, "omega+" or "omega-". Genetic crosses between yeast cells carrying different alleles led to highly distorted inheritance in the progeny, since almost all cells ended up carrying the "omega+" allele! In 1974, he proposed a model in which gene conversion of the "omega-" allele to "omega+" was achieved by homologous recombination, replacing one allele by the other, copying in the process the flanking erythromycin and chloramphenicol mutations.
Bernard Dujon | The early years : discovery of the first homing endonuclease
Contractile vacuoles ("stars") were first observed by Spallanzani (1776) in protozoa, although mistaken for respiratory organs. Dujardin (1841) named these "stars" as "vacuoles". In 1842, Schleiden applied the term for plant cells, to distinguish the structure with cell sap from the rest of the protoplasm. In 1885, de Vries named the vacuoule membrane as tonoplast.
Vacuole | Discovery
Ranvier was born and studied medicine at Lyon, graduating in 1865. He founded a small private research laboratory with Victor André Cornil, and together they offered a course in histology to medical students. They also wrote together an influential textbook on histopathology. In 1867, Ranvier entered the Collège de France and worked as an assistant to Claude Bernard. In 1875, he was appointed to its chair of general anatomy. In 1878, Ranvier discovered the nodes which received his name. Other anatomical structures bearing his name are the Merkel-Ranvier cells, melanocyte-like cells in the basal layer of the epidermis that contain catecholamine granules; and Ranvier's tactile disks, a special type of sensory nerve ending.
Louis-Antoine Ranvier | Career
Bergeron pioneered in Quebec and Canada, he elucidated the major resident proteins of the secretory pathway common to all cells. This led to the discovery of several proteins characterized for the first time involved in organ biogenesis and disease.
John J. M. Bergeron | Research and scientific career
CBs were initially discovered by neurobiologist Santiago Ramón y Cajal in 1903 as small argyrophilic (readily stained by silver salts, literally "silver loving") spots in the nuclei of silver-stained neuronal cells. Because of their close association with nucleoli, he named them "nucleolar accessory bodies". Later on, they were forgotten and rediscovered multiple times independently which led to a state where scientists from different research fields used different names for the same structure. Names used for CBs included "sphere organelles", "Binnenkörper", "nucleolar bodies" or "coiled bodies". The name coiled bodies comes from observation of electron microscopists Monneron and Bernhard. They described bodies as aggregates composed of coiled threads with thickness of 400–600 Å.
Cajal body | History
Devoted to medical research, he initially joined German institutes in Berlin. In 1929 he found an opportunity to join the Rockefeller Institute in New York. At Rockefeller University he made his most groundbreaking achievements in cell biology. In 1930 he developed the technique of cell fractionation, by which he discovered the agent of the Rous sarcoma, components of cell organelles such as mitochondrion, chloroplast, endoplasmic reticulum, Golgi apparatus, ribosome and lysosome. He was the first to employ the electron microscope in the field of biology. In 1945 he published the first detailed structure of cell. His collective works established the complex functional and structural properties of cells.
Albert Claude | Introduction
Anthony William Linnane (1930–2017) was an Australian professor of biochemistry, known for his work on mitochondria.
Anthony William Linnane | Introduction
Mitochondria and chloroplasts are eukaryotic organelles that originated as bacterial endosymbionts, so there was much interest in whether they use FtsZ for division. Chloroplast FtsZ was first discovered by Osteryoung, and it is now known that all chloroplasts use FtsZ for division. Mitochondrial FtsZ was discovered by Beech in an alga; FtsZ is used for mitochondrial division in some eukaryotes, while others have replaced it with a dynamin-based machinery.
FtsZ | History
He published his findings in an article titled "Sull'anatomia e fistologia della retina". On 12 November 1876, he reported his discovery to the Berlin Academy.
Franz Christian Boll | Introduction
As chromatoid body is significantly bigger than other known RNP granules it is seen even with light microscopy and was discovered already in 1876 by A. von Brunn.
Chromatoid body | Introduction
Golgi studied kidney function during 1882 to 1889. In 1882, he published his observations on the mechanism of renal hypertrophy, which he understood to be due to renal cell proliferation. In 1884, he described tubular cell mitoses in the kidney of a person suffering from tubulointerstitial nephritis, and he noted that the process was an essential part of repairing the kidney tissue. He was the first to dissect out intact nephrons, and show that the distal tubulus (loop of Henle) of the nephron returns to its originating glomerulus, a finding that he published in 1889 ("Annotazioni intorno all'Istologia dei reni dell'uomo e di altri mammifieri e sull'istogenesi dei canalicoli oriniferi".
Camillo Golgi | Kidney
A more accurate interpretation was made by J. David Robertson, who determined that the dark electron-dense bands were the headgroups and associated proteins of two apposed lipid monolayers. In this body of work, Robertson put forward the concept of the “unit membrane.” This was the first time the bilayer structure had been universally assigned to all cell membranes as well as organelle membranes.
History of cell membrane theory | Discovery of lipid bilayer structure
Between the 1930s and 1950s, Fritz Lipmann and others established the role of ATP as the universal carrier of energy in the cell, and mitochondria as the powerhouse of the cell. Such traditionally biochemical work continued to be very actively pursued throughout the 20th century and into the 21st.
History of biology | Biochemistry, microbiology, and molecular biology
He returned to New York City in 1975, for a year-long sabbatical at Rockefeller University working with Jim Darnell. In 1975, at the age of 37, he shared the Nobel Prize for Physiology or Medicine with Howard Temin and Renato Dulbecco. The citation reads, "for their discoveries concerning the interaction between tumor viruses and the genetic material of the cell." At the time, Baltimore's greatest contribution to virology was his discovery of reverse transcriptase (Rtase or RT) which is essential for the reproduction of retroviruses such as HIV and was discovered independently, and at about the same time, by Mizutani and Temin.
David Baltimore | MIT Cancer Center
He also performed extensive research of acarids (mites). In 1838, he published an influential work on comparative physiology, titled "Traité de physiologie comparée".
Antoine Louis Dugès | Introduction
He and Basil Lythgoe proved this to be the case. He gained his second PhD in 1952. He later worked on the selective phosphorylation of nucleosides to form nucleotides. This was the beginning of a lifelong career, and led to the chemical structures of RNA and, by inference, DNA.
Daniel McGillivray Brown | Biography
Many seminal discoveries have been published in the journal, including the first descriptions of numerous cellular functions and structures, such as the secretory pathway, mitochondrial and chloroplast DNA, microtubules, intermediate filaments, tight junctions (including occludins and claudins), adherens junctions, and cadherins.
Journal of Cell Biology | History
The classification of "Pelomyxa" has been the subject of considerable discussion, in recent decades. "Pelomyxa" lack mitochondria, as well as several other organelles usually found in eukaryote cells (notably, peroxisomes and dictyosomes). At one time, they were also believed to lack flagella and to be incapable of mitosis. As nucleated cells that lacked "nearly every other cell-inclusion of eukaryotes", "Pelomyxa" were, for a time, regarded as surviving "proto-Eukaryotes", standing somewhere between the bacteria and the modern cell. In 1973, it was proposed that the ancestors of "Pelomyxa palustris" had branched off from the eukaryote line before the advent of mitochondria In 1976, Jean M.
Pelomyxa | Classification
They described this membrane-like barrier as a "saclike structure surrounded by a membrane and containing acid phosphatase." It became clear that this enzyme from the cell fraction came from membranous fractions, which were definitely cell organelles, and in 1955 De Duve named them "lysosomes" to reflect their digestive properties. The same year, Alex B. Novikoff from the University of Vermont visited de Duve's laboratory, and successfully obtained the first electron micrographs of the new organelle. Using a staining method for acid phosphatase, de Duve and Novikoff confirmed the location of the hydrolytic enzymes of lysosomes using light and electron microscopic studies.
Lysosome | Discovery
He was the first to describe the loreal pits of the Crotalinae. Tyson however did not recognize its heat-sensing function, thinking it was a hearing organ.
Edward Tyson | Anatomical research
They were discovered in 1980 by Novick and Schekman, of the Department of Biochemistry, University of California, Berkeley.
Berkeley body | Introduction
In biology "organs" are defined as confined functional units within an organism. The analogy of bodily organs to microscopic cellular substructures is obvious, as from even early works, authors of respective textbooks rarely elaborate on the distinction between the two. In the 1830s, Félix Dujardin refuted Ehrenberg theory which said that microorganisms have the same organs of multicellular animals, only minor. Credited as the first to use a diminutive of "organ" (i.e., little organ) for cellular structures was German zoologist Karl August Möbius (1884), who used the term "organula" (plural of "organulum", the diminutive of Latin "organum"). In a footnote, which was published as a correction in the next issue of the journal, he justified his suggestion to call organs of unicellular organisms "organella" since they are only differently formed parts of one cell, in contrast to multicellular organs of multicellular organisms.
Organelle | History and terminology
He was the first person to describe siderocytes and sideroblasts, atypical nucleated erythrocytes with granules of iron accumulated in perinuclear mitochondria. This he reported in the journal "Nature". The Grüneberg ganglion, an olfactory ganglion in rodents, was first described by Hans Grueneberg in 1973.
Hans Grüneberg | Introduction
Hirsch "used these new tools to address the question of whether phagocytes contained preformed bactericidal substances or whether these substances developed after foreign particles were engulfed. They isolated granules from the rest of the cell contents, used phase and electron microscopy to visualize them, and determined chemically that they were lysosomes, the cell organelles recently identified by Belgian biochemist Christian de Duve. These discoveries, which traced the phagocytic digestive system to the fusion of phagocytic vacuoles and lysosomes, became widely available to the community after Jim and Zan made a remarkable series of films showing living phagocytes discharging their abundant lysosomes to kill bacteria."
Zanvil A. Cohn | Rockefeller Institute for Medical Research
A cranidium of "Atractopyge" was already illustrated by the Welsh scientist Edward Lhuyd in 1698.
Atractopyge | History
In this body of work, Robertson put forward the concept of the “unit membrane.” This was the first time the bilayer structure had been universally assigned to all cell membranes as well as organelle membranes.
Lipid bilayer | History
Although this idea was initially greeted with skepticism, Vance was able to reconstitute the transfer of newly made lipids to mitochondria in a cell-free system. She purified "Fraction X", renaming it the mitochondria-associated membrane (MAM) fraction, and showed that it contained highly active enzymes able to synthesize a variety of membrane components. She proposed that the MAM might function as a "membrane bridge" between the endoplasmic reticulum and the mitochondria. Although Vance's work was ahead of its time, it was rediscovered in the late 2000s when other researchers began to identify specific proteins, called tethers, that form the contact points between organelles.
Jean Vance | Career
He founded his classification of all organised beings on the consideration of each individual organ. As each organ gave birth to new relations, so he established a corresponding number of arbitrary arrangements. Those beings possessing the greatest number of similar organs were referred to one great division, and the relationship was considered more remote in proportion to the dissimilarity of organs.
Michel Adanson | Personal history
Accepting the Nobel Prize for this work in 1962, Watson cited one of Daly's papers on "The role of ribonucleoprotein in protein synthesis" as contributing to his work. After 1953, the cell nucleus research field was flooded with funding opportunities.
Marie Maynard Daly | Proteins
When diagramed, the resulting structure looks like the letter D. The D-loop was first discovered in 1971 when researchers noticed that many DNA in the mitochondria they were examining under microscope contained a short segment that was tripled stranded.
D-loop replication | Introduction
Till & McCulloch are James Till and Ernest McCulloch who, while studying the effect of radiation on the bone marrow of mice at the Ontario Cancer Institute, in Toronto, demonstrated the existence of multipotent stem cells in 1961.
Till &amp; McCulloch | Introduction
Later, part of the 1997 Nobel Prize in Chemistry was awarded to Paul D. Boyer and John E. Walker for their clarification of the working mechanism of ATP synthase.
Mitochondrion | NADH and FADH: the electron transport chain
This high amount of mitochondria is reported to be a result of mutations in the mitochondrial DNA. Some scientists have identified these mutations as deletions in the mitochondrial DNA of Hürthle cells found in neoplasms and Hashimoto's thyroiditis.
Hürthle cell | Histology
In 1982, a cognate receptor for the Signal Recognition Particle (SRP) was discovered and characterized in the ER membrane. In 1972, Sabatini moved his laboratory to the New York University School of Medicine to become the chair of the Department of Cell Biology, where he assembled a group that focused on the study of membrane and organelle biogenesis. Initially, that work placed a primary emphasis on identifying structural features of secretory, lysosomal and integral membrane proteins that are synthesized on membrane bound ribosomes, address them to specific subcellular locations and determine their disposition within a membrane.
David D. Sabatini | Academic career