Transcriptome analysis of the potential roles of FOXL2 in chicken pre-hierarchical and pre-ovulatory granulosa cells.

Forkheadbox L2 (FOXL2) is a transcription factor involved in mammalian ovarian development, especially in granulosa cell differentiation. However, this factor's function in mature chicken ovary is unclear. To explore the function of FOXL2 in chicken granulosa cells, we performed RNA-seq to compare the transcriptomes of pre-hierarchical (phGCs) and pre-ovulatory granulosa cells (poGCs) by FOXL2 overexpression. We observed that focal adhesion might be one of the key pathways activated during the differentiation of granulosa cells, and FOXL2 might be involved in follicle selection by regulating the expression of cytokines and the concentration of cyclic adenosine monophosphate (cAMP). Interestingly, we observed that FOXL2 played different roles in phGCs and poGCs, which might contribute to homeostasis in the chicken follicle by inducing differentiation of granulosa cells in pre-hierarchal follicles and preventing premature ovulation in pre-ovulatory follicles. Taken together, the results of our study establish a framework for understanding the potential functions of FOXL2 in the chicken granulosa cell.