Multifunctional Nature of Protostomian Gonadotropin-Releasing Hormone-Like Molecules

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

Evolution is driven, in part, by changes in the function of molecules that control the physiology of the organism. Studying these changes is crucial for understanding the unique adaptations developed by organisms to survive the test of time. One molecule whose change over time can influence evolution is a hormone called gonadotropin-releasing hormone (GnRH). GnRH activates reproduction to ensure the propagation of all vertebrate species. In invertebrates, GnRH is assumed to also activate reproduction although consistent support for such an assumption is lacking. It is hypothesized that invertebrate GnRH is not universally important to reproductive activation in invertebrates. Instead, invertebrate GnRH may assume a wide range of functions in neural, motor, and metamorphic control. The project investigates non-reproductive function of GnRH and a related peptide in an invertebrate animal, the sea slug Aplysia californica. These studies may reveal non-reproductive roles of GnRH critical to the survival of invertebrate species. To study the non-reproductive function of GnRH and the related peptide, adipokinetic hormone, a combination of whole organism studies and molecular and biochemical techniques will be used. The investigators will address the following aims: 1) Examine the role of GnRH in metamorphic development, 2) Perform in vitro functional analysis of GnRH receptor isoforms, investigate their distribution, and 3) Investigate the function of adipokinetic hormone. The work challenges a vertebrate-centric notion that invertebrate hormones essentially function as their vertebrate counterparts. This conceptual shift is important for advancing our knowledge on how changes in hormone function contribute to the survival, adaptation, and evolution of metazoans. For broader impacts, this project will provide Dr. Tsai with opportunities for: (1) undergraduate training, (2) minority recruitment, (3) inter-departmental and trans-Pacific collaborations, (4) information dissemination via the development of a novel website that uses humor and cartoons to engage K-12 students in comparative reproduction, and (5) outreach activities to showcase sea slugs to middle school students. Data collected from these studies will be shared through peer-reviewed publications and the Invertebrate Brain Platform http://invbrain.neuroinf.jp/modules/htmldocs/IVBPF/Top/index.html.