Renyta Moses

This project represents the different levels of expression of the gene Follistatin-Like (FST-Like) in the developmental stages of male and female Astatotilapia burtoni, a close relative of Tilapia. FST-Like codes for the gonadal protein, Follistatin, which inhibits the release of the follicle-stimulating hormone (FSH) in mammals. This hormone is responsible for the growth of the female ovarian follicle that leads to the release of an egg; in fish, FSH aids in early gonadal development and vitellogenesis. Apart from Follistatin’s inhibitory functions, it has been known to play an important role in muscle growth. Since male tilapias are larger than female tilapias, and Follistatin inhibits a female gonadal hormone, I hypothesized that males will have a higher expression of FST-Like. qPCR and statistical methods such as ANOVA were utilized to obtain and analyze data for both brain and gonad tissues of males and females at 10 days post-fertilization and 14 days post-fertilization. The findings, although statistically insignificant, indicated that FST-Like was more highly expressed in females than in males; this rejects my initial hypothesis and suggests a different function of FST-Like in cichlids. Since males have a larger body mass than females, understanding the genes that play a role in the sex determination of cichlids is important; manipulating this pathway to produce large males could allow for more sustainable and economic ways to cultivate these fish both for the research and food industry.