The Molecular Underpinning of Life-History Evolution: Roles of the IIS network and the Building of a Reptilian Model

Abstract

The Insulin and Insulin-like Signaling (IIS) network regulates cellular processes including pre- and post-natal growth, cellular development, wound healing, reproduction, and longevity. Despite their importance on the physiology of vertebrates, the study of the specific functions of the top regulators of the IIS network — insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) has been mostly limited to a few model organisms, namely lab-rodents. My dissertation aims to build a foundation for the development of a reptilian model to study IIS in the context of early life growth and reproduction. Towards this aim, the chapters of my dissertation (1) demonstrate that the expression patterns of IGF1 and IGF2 seen in lab-rodents are atypical relative to the typical patterns across amniotic clades, including humans; (2) characterize the gene expression of IGFs and IGFBPs across tissues and developmental stages in a model reptile, the brown anole lizard (Anolis sagrei); (3) discover that forced investment in tail regeneration results in increased investment in reproduction in the brown anole; and (4) demonstrate how a CURE focused on novel IIS research can be an effective teaching tool in the undergraduate biology classroom.