The Role of the Dorsomedial Hypothalamic Nucleus in Mediation of Seasonal Reproductive Rhythms in the Siberian Hamster

Morgan Burke : Molecular and Cell Biology/Integrative Biology

Mentor: Professor Irving Zucker, Psychology and Integrative Biology

Morgan’s fascination with neurobiology led her to join the laboratory of Prof. Irving Zucker , where she has been studying the neuroendocrine basis of seasonal rhythms. Siberian hamsters, like most mammals, restrict production of offspring to the spring and summer. They do so by measuring day length. Neural and endocrine tissues decode day length by measuring the duration of nocturnal melatonin secretion. Morgan’s study, which will serve as the basis of her senior thesis, will assess whether the dorsomedial hypothalamic nucleus, a brain melatonin target tissue, is a necessary and sufficient component of the neural substrate that measures nightly melatonin duration and consequently day length. This project addresses a fundamental issue in regulatory biology and is of potential value in controlling and preserving animal populations.