Our laboratory focuses on the effects of natural and human-derived stressors on reproduction and development of marine organisms. We utilize developing systems as sensitive yet simple models for understanding mechanisms of toxicity and environmental stress. In addition, we investigate the physiological mechanisms by which these systems tolerate environmental stress.
The laboratory essentially has two main foci. The first is more basic in nature and deals with molecules and physiological mechanisms involved in fertilization and early development. The second is focused on the impacts of pollutants and altered habitats on early life stages that may ultimately lead to changes in populations. An example of the first focus is our study of the mechanisms of sperm motility initiation in Pacific herring from the San Francisco Bay estuary and the egg-derived ligand that signals the intracellular ionic changes and subsequent motility initiation (Drs. Carol Vines and Fred Griffin). These sperm have evolved a unique mode of motility initiation in that they surprisingly remain immotile in the environment for hours until they contact an egg, at which time an extracellular glycoprotein stimulates an ionic cascade resulting in flagellar motion. These ionic events are dependent on lowered salinity (in particular Na+) that is typical in the winter months in the estuary. We have found that sperm motility initiation, successful fertilization, embryo development, and even larval survival and growth are dependent on the lowered salinities that occur in normal years in the estuary. We are collaborating with colleagues in Japan to investigate both the basic ionic signaling events in sperm motility initiation as well as differences in salinity tolerance of herring populations along the Pacific Rim. In addition to research on non-mammalian systems, we have been investigating the role of DEFB126, a beta-defense that coats the mammalian sperm surface and “cloaks” sperm from being attacked by the female reproductive tract immune system (Ted Tollner, Ph.D. candidate). This glycoprotein is part of the innate immune system and is related to immuno-protective peptides used by invertebrates.
The second focus of the lab deals with both natural and anthropogenic stressors. For example, we are investigating the mechanisms by which phylogenetic differences in contaminant tolerance occur in embryos exposed to hydrophobic chemicals; these include polycyclic aromatic hydrocarbons, pharmaceuticals, and agrochemicals. This includes the study of the multidrug resistance transporter family of proteins and their expression in embryos/larvae as well as adult tissues (Nature McGinn, Ph.D. candidate). This research includes studies of the effects of environmental chemicals on axis determination in echinoderm and teleost fish embryos (Ellie Fairbairn, Ph.D. candidate; Dr. Carol Vines). In another project, we are investigating reproductive impairment in California marsh fish, including endocrine disruption and the expression of egg chorion proteins in males exposed to estrogenic compounds. This is part of a larger program that was just completed to develop new indicators of condition of salt marsh organisms as part of a US EPA-supported program, PEEIR. Finally, we are investigating the effects of suspended sediments in San Francisco Bay on herring fertilization and development, including larval behavior (Drs. Fred Griffin and Ed Smith).
Cao, Y., G. N. Cherr, A. L. Córdova, T.W.-M. Fan, R.M. Higashi, M. G. LaMontagne, K.M. Scow, J. Yuan, and P. A. Holden. 2006 Relationships between Sediment Microbial Communities and Pollutants in Two California Salt Marshes, Microbial Ecology, In Press.
Roepke, T.A., A.M. Hamdoun, and G.N. Cherr. 2006 An increase in multidrug transport activity is associated with oocyte maturation in sea stars, Development, Growth, Differentiation, In Press.
Rajagopal, M., T.L. Tollner, W. Finkbeiner, G.N. Cherr, and J. Widdicombe. 2006 Differentiated structure and function of primary cultures of monkey oviductal epithelium, In Vitro Cellular and Developmental Biology-Animal, In Press.
Rose, W.L., R.M. Nisbet, P.G. Gree, S. Norris, T. Fan, E.H. Smith, G.N. Cherr, and S.L. Anderson. 2006 Using an integrated approach to link biomarker responses and physiological stress to growth impairment of cadmium-exposed larval topsmelt, Aquatic Toxicology, In Press.
Roepke, T.A., E.S. Chang, and G.N. Cherr. 2006 Maternal exposure to estradiol and endocrine disrupting compounds alters the sensitivity of sea urchin embryos and the expression of an orphan steroid receptor, Journal of Experimental Zoology, 305A:831-840.
Anderson, S.L., G.N. Cherr, S.G. Morgan, C.A. Vines, R.M. Higashi, W.A. Bennett, W.L. Rose, A. Brooks, R.M. Nisbet. 2006 Integrating contaminant responses in indicator saltmarsh species, Marine Environmental Research, 62:S317-S321.
Ellis-Hutchings, R.G., G.N. Cherr, L.A. Hanna, and C.L. Keen. 2006 Polybrominated diphenyl ether (PBDE)-induced alterations in vitamin A and thyroid hormone concentrations in the rat during lactation and early postnatal development, Toxicology and Applied Pharmacology, 215:135-145.
Roepke, T.A., M.J. Snyder, and G.N. Cherr. 2005 Estradiol and endocrine disrupting compounds adversely affect development of sea urchin embryos at environmentally relevant concentrations, Aquatic Toxicology, 71:155-173.
Friedman, C.S., H.M. Brown, T.W. Ewing, F.J. Griffin, and G.N. Cherr.2005 Pilot study of the Olympia oyster Ostrea conchaphila in the San Francisco Bay estuary: Description and distribution of diseases., Diseases of Aquatic Organisms, 65:1-8.
Yudin, A.I., S.E.Generao, T.L.Tollner, C.A. Treece, J.W. Overstreet, and G.N. Cherr. 2005 ESP13.2 on the cell surface protects sperm from immunorecognition and binding of Anti-sperm antibodies., Biology of Reproduction, 73:1243-1252.
Yudin, A.I., C.A. Treece, T.L. Tollner, J.W. Overstreet, G.N. Cherr. 2005 The Carbohydrate Structure of DEFB126, the Major Component of the Cynomolgus Macaque Sperm Plasma Membrane Glycocalyx, Journal of Membrane Biology, 207(2):110-129.
Rose, W.L., J. Hobbs, R. Nisbet, P.G. Green, G. Cherr, S.A. Anderson. 2005 Validation of Otolith Growth Rate Analysis Using Cadmium-Exposed Larval Topsmelt (Atherinops affinis), Environmental Toxicology and Chemistry, 24(10):2612-2620.
Griffin, F.J., M.R, Brenner, H.M. Brown, E.H. Smith, C.A. Vines, and G.N. Cherr. 2004 Survival of Pacific herring larvae is a function of external salinity, In: Larval Fish Ecology in the San Francisco Estuary and Watershed, American Fisheries Society Symposium, 39:37-46.
Brown, H.M., A. Briden, T. Stokell, F.J. Griffin, and G.N. Cherr. 2004 Thermotolerance and Hsp70 Profiles in Adult and Embryonic California Native Oysters, Ostrea conchaphila (Carpenter, 1857), Journal of Shellfish Research, 23(1):135-141.
Tollner, T.L, A.I. Yudin, C.A. Treece, J.W. Overtsreet, and G.N. Cherr. 2004 Macaque sperm release ESP13.2 and PSP94 during capacitation: The absence of ESP13.2 is linked to sperm-zona recognition and binding, Molecular Reproduction and Development, 69:325-337.
Hamdoun, A.M., G.N. Cherr, T.A. Roepke, and D. Epel. 2004 Activation of multidrug efflux transporter activity at fertilization in sea urchin embryos (Strongylocentrotus purpuratus), Developmental Biology, 276:452-462.
Watters, D.L., H.M. Brown, F.J. Griffin, E.J. Larson, and G.N. Cherr. 2004 Pacific Herring spawning grounds in San Francisco Bay: 1973- 2000, In: Larval Fish Ecol