Degree Type
Honors Capstone Project
Date of Submission
Spring 5-1-2018
Capstone Advisor
Melissa Pepling
Honors Reader
Donna Korol
Capstone Major
Biology
Capstone College
Arts and Science
Audio/Visual Component
no
Capstone Prize Winner
no
Won Capstone Funding
no
Honors Categories
Sciences and Engineering
Subject Categories
Biology | Cell and Developmental Biology | Life Sciences
Abstract
Women are born with the all the germ cells they will produce in their lifetime, with the establishment of this initial pool of germ cells being critical for fertility. In the mouse model, germ cells arrive at the genital ridge around 10.5 days post coitum (dpc) and divide by mitosis, forming cysts, until 13.5 dpc. These germ cells, referred to as oocytes, enter meiosis and begin to arrest in the diplotene stage of prophase I around 17.5 dpc. Simultaneously, the cysts begin to break apart and flattened granulosa cells surround the remaining single oocytes to form primordial follicles. Most oocytes remain arrested in the primordial follicle stage until sexual maturity, while a subset of the population progresses past the primordial follicle stage in a process known as the first wave of follicle development. During this process, a portion of the follicles are activated and progress through the primary and secondary follicle stage, until they eventually reach the antral follicle stage before dying off. Not much is known about the mechanisms of this first wave of follicle development or its implications for the initial pool of oocytes. Previous work has shown that culturing ovaries in the presence of insulin promoted the transition from primordial to primary follicles, though insulin’s mechanisms and effects on follicle development have yet to be determined. This project utilized immunocytochemistry, western blotting, and organ culture to elucidate some of the mechanisms by which insulin signals in the oocyte and to determine its effects on follicle formation and activation. Results support previous work suggesting that insulin signaling promotes follicle activation, and establish that insulin signaling may play a limited role in follicle development. Ovaries grown in culture with higher concentrations of insulin had both a greater percentage of primary follicles and fewer oocytes in cysts, suggesting that insulin plays a role in follicle development throughout the reproductive lifespan.
Recommended Citation
Abdullah, Ali, "The Effects of Insulin Signaling on Follicle Development and Activation" (2018). Renée Crown University Honors Thesis Projects - All. 1185.
https://surface.syr.edu/honors_capstone/1185
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
