Jerri L. Bartholomew
Director, J.L. Fryer Aquatic Animal Health Laboratory
Connect with Jerri
Nash Hall 524 jerri.bartholomew@oregonstate.edu (541) 737-1834
Bartholomew Lab
Ph.D., Oregon State University
Our research focuses on the pathogens that affect the health of wild Pacific salmon populations, particularly myxozoan parasites, which have a complex life cycle, requiring both a fish and annelid host.
Disease Effects on Wild Populations
The myxozoan Ceratonova shasta is endemic across the Pacific NW and causes high mortality in juvenile salmon in some river systems. A long-term project in the Klamath River integrates monitoring and research to develop recommendations for fishery management by providing real time data on parasite densities and their predicted effects on juvenile salmon, and by linking areas of high disease risk with physical parameters such as water flows and temperature. We are applying similar approaches to the Deschutes River. Research in the Willamette River further investigates C. shasta dynamics in this system as well as conducting surveys for parasites of native and introduced fishes.
Interactions Between Hatchery and Wild Fish
Research being conducted in the Willamette River basin investigates pathogen transmission between hatchery populations and naturally reproducing populations. We are also looking at the effects of multiple infections on salmon survival.
Climate Change Effects on Disease
Climate change is expected to have profound effects on host-pathogen interactions. We are examining how this might affect myxozoan disease by developing predictions for how the phenology of parasite life cycles will change under future climates, how changing flow dynamics will alter disease, and to identify river habitats that should be protected as refugia.
Parasite Evolution and Diversity
Myxozoans not only have complex life histories, but enigmatic relationships as revealed by molecular sequence analysis. Continued investigations into the genetics of C. shasta have revealed that it is actually a parasite complex, with different strains specifically evolving with different salmonid hosts. This finding has caused us to rethink assumptions about host-parasite interactions. We are currently involved in genome sequencing and transcriptomic studies that will aid us in developing better diagnostic tools as well as to answer questions about basic parasite biology and phylogenetic relationships.
Parasite Invasion
The first step in Myxozoan infection is activation of their polar capsules. These specialized cells resemble the nematocysts of their cnidarian relatives and could offer possibilities for development of therapeutants. We are working with Israeli scientists to understand the physical process and the genes that control it, as well as to test candidate treatments that affect the process.
Evolution of the Immune System and Role of Mucosal Immunity
This salmonid-C. shasta relationship has proved an ideal model for investigating mucosal immunity in a primitive host and is the basis for a collaboration with Oriol Sunyer, University of Pennsylvania, funded by the National Science Foundation and National Institutes of Health.
Salmon Diseases
Myxozoan Parasites
Host Resistance Mechanisms
Parasite Evolution
Americus, B., Hams, N., Klompen, A.M.L., Alama-Bermejo, G., Lotan, T., Bartholomew, J.L., and Atkinson, S.D. Accepted September 2021. The cnidarian parasite Ceratonova shasta utilizs inherited and recruited venom-like compounds during infection. PeerJ.
Brekhman, V., Ofek-Lalzar, M., Atkinson, S.D., Alama-Bermejo, G., Maor-Landaw, K., Malik, A., Bartholomew, J.L., and Lotan, T. 2021. Proteomic analysis of the parasitic Cnidarian Ceratonova shasta (Cnidaria: Myxozoa) reveals diverse roles of actin in motility and spore formation. Front. in Mar. Sci. 8:632700.
Kumar, G., Ertl, R., Nilsen, F., Bartholomew, J.L., and El-Matbouli, M. 2021. Data of de novo transcriptome assembly of the myxozoan parasite Tetracapsuloides bryosalmonae. Data Brief 35:106831.
Barrett, D.E. and Bartholomew, J.L. 2021. A tale of two fish: Comparative transcriptomics of resistant and susceptible steelhead following exposure to Ceratonova shasta highlights differences in parasite recognition. PLoS One. 16(2):e0234837.
Americus, B., Schisler, G.J., Bartholomew, J.L., and Atkinson, S.D. 2021. Myxobolus cerebralis Causes Presporogonic Mortality in Juvenile Mountain Whitefish. J. of Aquatic Animal Hlth. 33(2):116-122.
Bartošová-Sojková, P., Kyslík, J., Alama-Bermejo, G., Hartigan, A., Atkinson, S.D., Bartholomew, J.L., Picard-Sánchez, A., Palenzuela, O., Faber, M.N., Holland, J.W., and Holzer, A.S. 2021. Evolutionary Analysis of Cystatins of Early-Emerging Metazoans Reveals a Novel Subtype in Parasitic Cnidarians. Biology 10(2):110.
Americus, B., Bartholomew, J.L., Lotan, T., and Atkinson, S.D. 2020. A comparison of the structure and function of nematocysts in free-living and parasitic cnidarians (Myxozoa). International Journal for Parasitology, 50: 763-769. DOI:10.1016/j.ijpara.2020.04.012
Americus, B., Austin, B., Lotan, T., Bartholomew, J., and Atkinson, S. 2020. In vitro and in vivo assays reveal that cations affect nematocyst discharge in Myxobolus cerebralis (Cnidaria: Myxozoa). Parasitology, 147(12):1352-1358. DOI:10.1017/S0031182020001158
Kyger, R., Luzuriaga, A., Peri, S., Layman, T., Sandberg, T.O.M., Singh, D., Atkinson, S.D., Bartholomew, J.L., Huchon, D., Soojin, V., and Alvarez-Ponce, D. 2020. Myxosporea (Myxozoa, Cnidaria) lack DNA cytosine methylation. Molecular Biology and Evolution, msaa214. DOI:10.1093/molbev/msaa214
Tilic, E., Atkinson, S.D., Rouse, G. 2020. Mitochondrial genome of the freshwater annelid Manayunkia occidentalis Mitochondrial DNA Part B: Resources, 5(3): 3313-3315. DOI:10.1080/23802359.2020.1815604
Alama-Bermejo, G,, Meyer, E., Atkinson, S.D., Holzer, A.S., Wiśniewska, M.W., Kolísko, M., and Bartholomew, J.L. 2020. Transcriptome-wide comparisons and virulence gene polymorphisms of host-associated genotypes of the cnidarian parasite Ceratonova shasta in salmonids. Genome Biology and Evolution, 12(8), 1258-1276. DOI:10.1093/gbe/evaa109
Taggart-Murphy, L., Alama-Bermejo, G., Dolan, B., Takizawa, F., and Bartholomew, J. 2020. Differences in inflammatory responses of rainbow trout infected by two genotypes of the myxozoan parasite Ceratonova shasta. Dev Comp Immunol. Aug 23;114:103829. doi: 10.1016/j.dci.2020.103829.
Kumar, G., Ertl, R., Bartholomew, J.L., and El-Matbouli, M. 2020. Transcriptome Analysis Elucidates the Key Responses of Bryozoan Fredericella sultana during the Development of Tetracapsuloides bryosalmonae (Myxozoa). Int J Mol Sci. Aug 17;21(16):5910. doi: 10.3390/ijms21165910.
Yahalomi, D., Atkinson, S.D., Neuhof, M., Chang. E., Philippe, H., Cartwright, P., Bartholomew, J.L., and Huchon, D. 2020. A cinidarian parasite of salmon (Myxozoa: Henneguya) lacks a mitochondrial genome. Proc Natl Acad Sci U S A. 2020 Mar 10;117(10):5358-5363. doi: 10.1073/pnas.1909907117. Epub 2020 Feb 24. PMID: 32094163
Richey, C.A., Kenelty, K.V., Hopkins, K.V.S., Stevens, B.N., Martinez-López, B., Hallett, S.L., Atkinson, S.D., Bartholomew, J.L., and Soto, E. 2020. Validation of environmental DNA sampling for determination of Ceratonova shasta (Cnidaria: Myxozoa) distribution in Plumas National Forest, CA. Parasitol. Res. PMID: 31897785.
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