Project description:Female reproductive senescence results from the regulated depletion of a finite pool of oocytes called the ovarian reserve. This pool of oocytes is initially established during fetal development, but the oocytes that comprise it must remain quiescent for decades until they are activated during maturation in adulthood. In order for developmentally competent oocytes to populate the ovarian reserve they must successfully initiate both meiosis and oogenesis. As the factors that regulate the timing and fidelity of these early events remain elusive, we assessed the precise function and timing of the transcriptional regulator TAF4b during meiotic prophase I progression in mouse fetal oocytes. Compared to matched controls, E14.5 Taf4b-deficient oocytes enter meiosis I in a timely manner however, their subsequent progression through the pachytene- to-diplotene transition of meiotic prophase I is compromised. Moreover, this disruption of meiotic progression is associated with the reduced ability of Taf4b-deficient oocytes to repair double-strand DNA breaks. Transcriptional profiling of Taf4b-deficient oocytes reveals that between E16.5 and E18.5 these oocytes fail to coordinate the reduction of meiotic gene expression and the induction of oocyte differentiation genes. These studies reveal that TAF4b promotes the formation of the ovarian reserve in part by orchestrating the timely transition to meiosis I arrest and oocyte differentiation, which are often perceived as separate events.
Project description:Research has shown that Taf4b-deficient female mice display excessive perinatal germ cell death, delayed germ cell cyst breakdown, and increased chromosome asynapsis. Therefore, we hypothesized that TAF4b, as part of TFIID, regulates oogenesis and meiotic gene programs. However, the transcriptomic effects of Taf4b-deficiency and how this may lead to the infertility we observe in mice has not yet been studied. Therefore, we performed RNA-seq to examine gene expression changes in E16.5 female Taf4b-heterozygous and Taf4b-deficient germ cells
Project description:Research has shown that Taf4b-deficient female mice display excessive perinatal germ cell death, delayed germ cell cyst breakdown, and increased chromosome asynapsis. Therefore, we hypothesized that TAF4b, as part of TFIID, regulates oogenesis and meiotic gene programs. However, the transcriptomic effects of Taf4b-deficiency and how this may lead to the infertility we observe in mice has not yet been studied. Therefore, we performed RNA-seq to examine gene expression changes in E14.5 female Taf4b-wildtype, Taf4b-heterozygous, and Taf4b-deficient germ cells
Project description:Taf4b-deficient male mice are initially sub-fertile and become infertile due to a depletion of the spermatogonial stem cell (SSC) reserve. During embryonic time points, significantly reduced numbers of germ cells have been observed in the Taf4b-deficient male gonad and previous research has shown that Taf4b mRNA expression peaks at E15.5. Therefore, we hypothesized that TAF4b, as part of TFIID, regulates cell cycle and SSC gene programs. We performed RNA-seq to examine gene expression changes in E14.5 and E16.5 male Taf4b-wildtype, Taf4b-heterozygous, and Taf4b-deficient germ cells
