Kristy L. Forsgren

The regulation of gonadal growth and development in fishes prior to the onset of puberty

While much is known about the regulation of gonadal development after puberty in vertebrates, relatively little is known about the biochemical and molecular processes involved in early gonadal growth and development. I am particularly interested in early ovarian development and the transition between primary and secondary ovarian follicle growth (i.e. transition from immaturity to sexual maturity). Early ovarian development is of particular interest because this is when stockpiles of maternal RNAs and proteins, which will eventually support embryonic development, are laid down. The proteins incorporated into the developing egg are thought to contribute to high quality eggs resulting in more robust larvae and increased survivorship. Additionally, in seasonally breeding animals, absolute fecundity, the maximum number of eggs that could potentially be ovulated per animal, is thought to be determined prior to puberty.

The Forsgren lab focuses on the factors that regulate and influence early embryonic and gonadal development in fishes. Our investigations encompass three areas of research: 1) the role of hormones in the control of growth and development, 2) the identification and function of putative proteins that are involved in regulating early embryonic and gonadal development, and 3) the impacts of endocrine disrupting compounds (anthropogenic chemicals that mimic native sex steroid hormones) on reproductive physiology.

Selected publications

Forsgren KL, S Qu, D Cwiertny, D Schlenk. 2014. Trenbolone acetate metabolites promote ovarian growth and development in adult Japanese medaka (Oryzias latipes). General and Comparative Endocrinology 202: 1-7

Bock, S. L., Chow, M. I., Forsgren, K. L., & Lema, S. C. (2021). Widespread alterations to hypothalamic-pituitary-gonadal (HPG) axis signaling underlie high temperature reproductive inhibition in the eurythermal sheepshead minnow (Cyprinodon variegatus). Mol Cell Endocrinol, 537, 111447. doi:10.1016/j.mce.2021.111447

Bond, E. R., & Forsgren, K. L. (2022). External reproductive structures of male Surfperches (Embiotocidae): Urogenital papilla. Anat Rec (Hoboken), 305(7), 1712-1723. doi:10.1002/ar.24836

Garcia, E., Rice, C. A., Eernisse, D. J., Forsgren, K. L., Quimbayo, J. P., & Rouse, G. W. (2019). Systematic relationships of sympatric pipefishes (Syngnathus spp.): A mismatch between morphological and molecular variation. J Fish Biol, 95(4), 999-1012. doi:10.1111/jfb.14073

Malik, A., Dickson, K. A., Kitagawa, T., Fujioka, K., Estess, E. E., Farwell, C., . . . Schuller, K. A. (2020). Ontogeny of regional endothermy in Pacific bluefin tuna (Thunnus orientalis). Marine Biology, 167(9). doi:10.1007/s00227-020-03753-3