Project description:Alternative splicing(AS) contributes to gene diversification through RNA-binding proteins, but AS regulation during germline development remains largely undefined. Here, we report a comprehensive set of mRNA splicing events mediated by epithelial splicing regulatory proteins 1(Esrp1) to regulate mouse oocyte development. Collectively, our data highlights that ESRP1-mediated AS program are required for oocyte development and female fertility maintainance.
Project description:Transcription and pre-mRNA alternative splicing are highly regulated processes that play major roles in modulating eukaryotic gene expression. It is increasingly apparent that other pathways of RNA metabolism, including small RNA biogenesis, can regulate these processes. However, a direct link between alternative pre- mRNA splicing and small RNA pathways has remained elusive. Here we show that the small RNA pathway protein Argonaute-2 (Ago-2) regulates alternative pre-mRNA splicing patterns of specific transcripts in the Drosophila nucleus using genome-wide methods in conjunction with RNAi in cell culture and Ago-2 deletion or catalytic site mutations in Drosophila adults. Moreover, we show that nuclear Argonaute-2 binds to specific chromatin sites near gene promoters and negatively regulates the transcription of the Ago-2-associated target genes. These transcriptional target genes are also bound by Polycomb group (PcG) transcriptional repressor proteins and change during development, implying that Ago-2 may regulate Drosophila development. Impor- tantly, both of these activities were independent of the catalytic activity of Ago-2, suggesting new roles for Ago-2 in the nucleus. Finally, we determined the nuclear RNA-binding profile of Ago-2, found it bound to several splicing target transcripts, and identified a G-rich RNA-binding site for Ago-2 that was enriched in these transcripts. These results suggest two new nuclear roles for Ago-2: one in pre-mRNA splicing and one in transcriptional repression. Input chromatin, 2 replicates of Ago2 ChIP-seq
Project description:Alternative splicing (AS) is generally observed in different developmental processes in mammals. In mammalian development, totipotency which is defined as the ability of a cell to give rise to all cell types of an entire organism is limited to early-stage preimplantation embryos. Somatic cell nuclear transfer (SCNT) can reprogram terminally differentiated cells into a totipotent state. However, studies addressing the functional role of AS in mammalian preimplantation embryonic development are lacking. Here we show that AS has important physiological functions in mammalian preimplantation embryonic development as a regulator. We discovered abundant AS transitions during both key events in preimplantation embryonic development, fertilization and embryonic genome activation. We also found that the RNA-binding protein hnRNPK govern the oocyte-to-embryo transition by regulating the MII oocyte-specific exon exclusion in mouse. Furthermore, we demonstrated that SCNT embryos had abnormal alternative splicing compared to in vitro fertilized (IVF) embryos in bovine. We used RNA-targeting system CRISPR-Cas13d to target cis elements of ABI2 pre-mRNA to operate alternative splicing, reducing abnormal isoform ratios of SCNT embryos and greatly improve the production of cloned cows. Our results advance the understanding of SCNT-mediated reprogramming and its potential applications for both reproductive and therapeutic cloning.
Project description:To delineate the developmental trajectory of oocyte during the process, we performed RNA-seq on single germ cells from newborn (P0.5) ovaries and identified a series of genes that may function between stage transitions. The significant decrease of meiosis-related genes and the dramatic increase of oocyte-specific genes marked the transition of germ cell to a functional oocyte. Our data highlighted the complexity of transcriptional control and depicted the regulatons and their regulatory networks in oocyte development. Besides that, our data first characterized patterns of alternative splicing events and linked isform usage differences to cellular stage transitions of folliculogenesis. In summary, this study reconstructed molecular cascades in oocytes and revealed the orchestration of transcription-splicing coupling regulation on follicle formation.
Project description:This SuperSeries is composed of the following subset Series: GSE30995: An Alternative Splicing Switch Regulates Embryonic Stem Cell Pluripotency and Reprogramming [RNA-Seq] GSE31006: An Alternative Splicing Switch Regulates Embryonic Stem Cell Pluripotency and Reprogramming [ChIP-Seq] GSE31007: An Alternative Splicing Switch Regulates Embryonic Stem Cell Pluripotency and Reprogramming [protein binding microarray] GSE31948: An Alternative Splicing Switch Regulates Embryonic Stem Cell Pluripotency and Reprogramming [AS microarray] Refer to individual Series
Project description:Gephyrin (GPHN) regulates the clustering of postsynaptic components at inhibitory synapses and is involved in pathophysiology of neuropsychiatric disorders. Here, we uncover an extensive diversity of GPHN transcripts that are tightly controlled by splicing during mouse and human brain development. Proteomic analysis reveals at least a hundred isoforms of GPHN incorporated at inhibitory Glycine and gamma-aminobutyric acid A receptors containing synapses. They exhibit different localization and postsynaptic clustering properties, and altering the expression level of one isoform is sufficient to affect the number, size, and density of inhibitory synapses in cerebellar Purkinje cells. Furthermore, we discovered that splicing defectsreported in neuropsychiatric disorders are carried by multiple alternative GPHN transcripts, demonstrating the need for a thorough analysis of the GPHN transcriptome in patients. Overall, we show that alternative splicing of GPHN is an important genetic variation to consider in neurological diseases and a determinant of the diversity of postsynaptic inhibitory synapses.