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Positive transcription elongation factor b (P-TEFb) is a RNA polymerase II carboxyl-terminal domain (Pol II CTD) kinase that phosphorylates Ser2 of the CTD and promotes the elongation phase of transcription. Despite the fact that P-TEFb has role in many cellular processes, the role of this kinase complex remains to be understood in mammalian early developmental events. In this study, using immunocytochemical analyses, we found that the P-TEFb components, CDK9, Cyclin T1 and Cyclin T2 were localized to nuclear speckles, as well as in nucleolar-like bodies in pig germinal vesicle oocytes. Using nascent RNA labeling and small molecule inhibitors, we showed that inhibition of CDK9 activity abolished the transcription of GV oocytes globally. Moreover, using fluorescence in situ hybridization, in absence of CDK9 kinase activity the production of ribosomal RNAs was impaired. We also presented the evidences indicating that P-TEFb kinase activity is essential for resumption of oocyte meiosis and embryo development. Treatment with CDK9 inhibitors resulted in germinal vesicle arrest in maturing oocytes in vitro. Inhibition of CDK9 kinase activity did not interfere with in vitro fertilization and pronuclear formation. However, when in vitro produced zygotes were treated with CDK9 inhibitors, their development beyond the 4-cell stage was impaired. In these embryos, inhibition of CDK9 abrogated global transcriptional activity and rRNA production. Collectively, our data suggested that P-TEFb kinase activity is crucial for oocyte maturation, embryo development and regulation of RNA transcription in pig. [ABSTRACT FROM AUTHOR]

Depression symptoms following immune response to a challenge have been reported after the recovery from sickness. A RNA-Seq study of the dysregulation of the microglia transcriptome in a model of inflammation-associated depressive behavior was undertaken. The transcriptome of microglia from mice at day 7 after Bacille Calmette Guérin (BCG) challenge was compared to that from unchallenged Control mice and to the transcriptome from peripheral macrophages from the same mice. Among the 562 and 3,851 genes differentially expressed between BCG-challenged and Control mice in microglia and macrophages respectively, 353 genes overlapped between these cells types. Among the most differentially expressed genes in the microglia, serum amyloid A3 (Saa3) and cell adhesion molecule 3 (Cadm3) were over-expressed and coiled-coil domain containing 162 (Ccdc162) and titin-cap (Tcap) were under-expressed in BCG-challenged relative to Control. Many of the differentially expressed genes between BCG-challenged and Control mice were associated with neurological disorders encompassing depression symptoms. Across cell types, S100 calcium binding protein A9 (S100A9), interleukin 1 beta (Il1b) and kynurenine 3-monooxygenase (Kmo) were differentially expressed between challenged and control mice. Immune response, chemotaxis, and chemokine activity were among the functional categories enriched by the differentially expressed genes. Functional categories enriched among the 9,117 genes differentially expressed between cell types included leukocyte regulation and activation, chemokine and cytokine activities, MAP kinase activity, and apoptosis. More than 200 genes exhibited alternative splicing events between cell types including WNK lysine deficient protein kinase 1 (Wnk1) and microtubule-actin crosslinking factor 1(Macf1). Network visualization revealed the capability of microglia to exhibit transcriptome dysregulation in response to immune challenge still after resolution of sickness symptoms, albeit lower than that observed in macrophages. The persistent transcriptome dysregulation in the microglia shared patterns with neurological disorders indicating that the associated persistent depressive symptoms share a common transcriptome basis. [ABSTRACT FROM AUTHOR]