Plant Research Reveals New Role for Gene Silencing Protein
News Mar 30, 2012
The expression of a gene, when an organism's DNA is transcribed into a useable product, requires activation via a promoter or an external trigger. Plant research to be published in Science helps to show that later stages of transcription are just as important. This is likely to apply to other organisms, including humans.
Termination is the final stage of transcription. Successful termination is dependent on DNA being transcribed into RNA with the correct sections, including a certain length tail.
Scientists at the John Innes Centre on Norwich Research Park have found that where effective termination through the normal mechanisms has not occurred, DICER-LIKE 4 (DCL4) steps in to tidy up. Without termination, transcription continues down the chromosome unchecked.
In this way, DCL4 plays a crucial and previously unknown role in transcription termination. It helps formation of the gene product. DCL4 is more commonly known to play a part in the opposite effect, gene silencing.
"DCL4 is a back-up to termination processes, helping a gene to be successfully expressed," said lead author Professor Caroline Dean from JIC, which is strategically funded by BBSRC.
The findings may help explain why gene silencing happens so often with transgenes. It was not known that so much attention should be given to the tail end of a gene.
"Our research shows that for successful expression the end of a gene is just as important as its beginning," said Dean.
When termination fails a lot of aberrant RNA is made -- this is degraded as part of a cell's quality control mechanism. This can have consequences for other sequences in the genome that match the aberrant RNA.
"If a gene ends badly, aberrant RNA will trigger silencing pathways," said Dean.
DCL4's ability to step in to rescue poor termination makes it important for both successful gene expression, a previously unknown role for it, and gene silencing.
Single-stranded Origami Technology Drives Drug Delivery Systems and Pharmaceutical Nanofactories ForwardNews
First nanotechnological approach enables the design and replication of complex single-stranded DNA and RNA origami with potential for drug delivery and nanofabrication.READ MORE
Bacterial Control Mechanism for Adjusting to Changing ConditionsNews
A fundamental prerequisite for life on earth is the ability of living organisms to adapt to changing environmental conditions. Physicists have now determined that the regulation mechanisms used by bacteria to adapt to different environments are based on a global control process that can be described in a single equation.READ MORE
Cracking the Code of Coenzyme Q BiosynthesisNews
Coenzyme Q is a vital cog in the body’s energy-producing machinery, a kind of chemical gateway in the conversion of food into cellular fuel. Researchers are developing new tools to shed light on CoQ function, primarily by finding and defining proteins that have a direct link to the chemical. This includes the development of a new multi-omic strategy to identify the global function of an RNA-binding protein that has long been associated with mitochondria and its role in CoQ biosynthesis.READ MORE