Researcher(s)
- Jacqueline Rima, Animal Science, University of Delaware
Faculty Mentor(s)
- Ashley Taylor, Animal and Food Sciences, University of Delaware
- Kathryn Ellwood, Animal and Food Sciences, University of Delaware
- Aditya Dutta, Animal and Food Sciences, University of Delaware
Abstract
Big data analysis has revolutionized our ability to identify drivers of complex biological
processes. Here we use programming language “R” to investigate drivers of laying hen’s reproductive
system. Just like humans, chicken have follicles on their ovaries that undergo growth and development.
Pre-recruitment follicles mature into pre-ovulatory follicles that later form an egg. When looking at a pre-
recruitment follicle and a pre-ovulatory follicle, it is easy to visually distinguish between the two as the
latter is much larger. However, how do they differ genetically? Only some of the genetic information in
DNA is transcribed to mRNA and that specific information gives a protein its function. In this study,
RNA was extracted from the two follicular types – pre-recruitment and pre-ovulatory follicle, and we used
differential gene expression analysis to determine which genes were expressed at significantly different
levels between the pre-ovulatory and pre-recruitment follicles. RStudio was used to identify highly
expressed genes and the database DAVID allowed us to conclude how the given genes interacted with
each other as well as the biological processes that took place. As follicles mature, they begin to facilitate
the production of several steroid hormones such as progesterone, androgen, and estrogen. With genes
such as CARTPT being highly expressed in pre-ovulatory follicles according to the dataset, it is logical to
conclude that it may play a role in steroidogenesis. Meanwhile, pre-recruitment follicles are more likely
to experience cell degeneration so genes like SFRP4 may be involved in modulating follicle cell survival
are likely important. These results allow for further investigation of how the genes identified control the
different stages of folliculogenesis and can serve as a point of reference when trying to understand what
takes place to enhance reproductive efficiency in layers and broiler breeders.