Project description:Offspring health outcomes are often linked with epigenetic alterations triggered by maternal nutrition and intrauterine environment. Strong experimental data also link paternal preconception nutrition with pathophysiology in the offspring, but the mechanism(s) routing effects of paternal exposures remain elusive. Animal experimental models have highlighted small non-coding RNAs (sncRNAs) as potential regulators of these effects. This study characterised the baseline sncRNA landscape of human sperm and the effect of a 6 week dietary intervention on their expression profile. 5’tRFs, miRNA and piRNAs were the most abundant sncRNA subtypes identified; their expression was associated with age, BMI and sperm quality. Nutritional intervention with vitamin D and omega-3 fatty acids altered expression of 3 tRFs, 15 miRNAs and 112 piRNAs, targeting genes involved in fatty acid metabolism and transposable elements in the sperm genome.
Project description:Paternal exposure to a range of environmental and lifestyle factors elicits distinct changes to the sperm sncRNA profile; modifications that have significant post-fertilization consequences. Despite this knowledge, there remains limited mechanistic understanding of how paternal exposures effect the sperm sncRNA landscape. Here, we report the acute sensitivity of the sperm sncRNA profile to the potent reproductive toxicant, acrylamide. Further, we traced the differential accumulation of acrylamide responsive sncRNAs to coincide with sperm transit of the proximal (caput) segment of the epididymis, wherein acrylamide exposure altered the expression of several transcription factors implicated in the expression of acrylamide-sensitive sncRNAs. We also identified extracellular vesicles secreted from the caput epithelium in relaying altered sncRNA profiles to maturing spermatozoa, the implications of which manifest in the form of dysregulated gene expression during early embryonic development. These data provide a causative mechanistic link to account for how environmental insults can alter the sperm epigenome and compromise the transcriptomic profile of early embryos
Project description:To find and fuse with the egg, mammalian sperm must complete an arduous voyage through the female reproductive tract. This odyssey is powered by the sperm tail, a specialized motile cilium. Mammalian sperm tails are reinforced at the molecular scale with sperm-specific microtubule inner proteins (sperm-MIPs), but the identities of these sperm-MIPs are unknown. Here, we report high-resolution cryo-electron microscopy structures of bovine sperm doublet microtubules (DMTs), allowing us to identify many sperm-MIPs. We also resolve structures of singlet MTs in the endpiece, revealing MIPs shared between singlet and doublet MTs. We demonstrate that at least two sperm-MIPs bind and stabilize MTs in vitro. Our structures shed light on ciliary diversity across cell types and provide structural frameworks for understanding molecular underpinnings of male infertility
Project description:Paternal exposure to environmental stressors elicits distinct changes to the sperm sncRNA profile; modifications that have significant post-fertilization consequences. Despite this knowledge, there remains limited mechanistic understanding of how paternal exposures modify the sperm sncRNA landscape. Here, we report the acute sensitivity of the sperm sncRNA profile to the reproductive toxicant, acrylamide. Further, we traced the differential accumulation of acrylamide-responsive sncRNAs to coincide with sperm transit of the proximal (caput) segment of the epididymis, wherein acrylamide exposure altered the abundance of several transcription factors implicated in the expression of acrylamide-sensitive sncRNAs. We also identified extracellular vesicles secreted from the caput epithelium in relaying altered sncRNA profiles to maturing spermatozoa, and dysregulated gene expression during early embryonic development following fertilisation by acrylamide-exposed spermatozoa. These data provide mechanistic links to account for how environmental insults can alter the sperm epigenome and compromise the transcriptomic profile of early embryos.
Project description:Analysis of sncRNA expression in 22 primary cSCC (10 from cSCCs that had evolved to histologically confirmed metastases, or MSCC, and 12 from a cSCC control group who had not developed any metastasis in a 5-year follow-up period). Unsupervised hierarchical clustering of the most variably expressed sncRNAs stratified the tumors into two groups, one formed mainly by NMSCC and the other formed exclusively by metastasizing cSCC, the latter displaying an overall sncRNA downregulation. Supervised clustering of MSCC vs. NMSCC identified the differential expression of 330 sncRNAs, most of them downregulated in the metastasizing group (248 sncRNAs; 75%). Functional and sequence-based classification of the probes in the array revealed alterations in the proportion of the snoRNAs represented in MSCCs when compared to their expression in NMSCCs.
Project description:Bovine respiratory epithelial cells have different susceptibility to bovine
respiratory syncytial virus infection. The cells derived from the lower
respiratory tract were significantly more susceptible to the virus than those
derived from the upper respiratory tract. Pre-infection with virus of lower
respiratory tract with increased adherence of P. multocida; this was not the
case for upper tract. However, the molecular mechanisms of enhanced
bacterial adherence are not completely understood. To investigate whether
virus infection regulates the cellular adherence receptor on bovine trachea-,
bronchus- and lung-epithelial cells, we performed proteomic analyses.
2020-07-28 | PXD019509 | JPOST Repository
Project description:small sncRNA sequencing of sperm
Project description:Male-derived accessory gland proteins (Acps) that are transferred to females during mating have profound effects on female reproductive physiology including increased ovulation, mating inhibition, and effects on sperm utilization and storage. The extreme rates of evolution seen in Acps may be driven by sperm competition and sexual conflict, processes which may ultimately drive complex interactions between female- and male-derived molecules and sperm. However, little is known of how gene expression in female reproductive tissues changes in response to the presence of male molecules and sperm. To characterize this response, we conducted parallel genomic and proteomic analyses of gene expression in the reproductive tract of 3-day-old unmated and mated female Drosophila melanogaster. Using DNA microarrays, we identified 539 transcripts that are differentially expressed in unmated vs. mated females and revealed a striking peak in differential expression at 6 hrs postmating and a marked shift from primarily down-regulated to primarily up-regulated transcripts within 3 hrs after mating. Combining two-dimensional gel electrophoresis and liquid chromatography mass spectrometry analyses, we identified 84 differentially expressed proteins at 3 hrs postmating, including proteins which appeared to undergo post-translational modification. Together, our observations define transcriptional and translational response to mating within the female reproductive tract and suggest a bimodal model of postmating gene expression initially correlated with mating and the final stages of female reproductive tract maturation and later with the declining presence of male reproductive molecules and with sperm maintenance and utilization. Experiment Overall Design: Three-day-old mated and unmated females were dissected to remove the lower reproductive tract (upper uterus, sperm-storage organs, and accessory glands). Mated females were dissected either immediately following mating (0 hr) or at 3, 6, or 24 hrs following the termination of mating. Tracts of 12-40 females of like category were pooled and total RNA extracted via a TRIzol-based protocol. Processing and labeling of transcript was performed by the Molecular Biology Core Facility at the Medical College of Georgia. Arrays from mated females at the different timepoints were compared to unmated females.