Project description:To investigate the role of motor neuron autophagy in ALS, we generated mice in which the critical autophagy gene Atg7 was specifically disrupted in motor neurons (Atg7 cKO). We also bred these mice to the SOD1G93A mouse model of ALS. Then we performed RNA sequencing on lumbar spinal cords from these mice to determine how motor neuron autophagy inhibition altered gene expression.
Project description:miRNAs are post-transcriptional repressors with wide variation in cellular abundance across cell types and disease states. Yet, the transcriptomic and biological impact of altering miRNA levels (rather than binary gain or loss) has not been systematically investigated. By genetic combination, we generated an allelic series of mice expressing varying levels of miR-218, a motor neuron-specific miRNA associated with amyotrophic lateral sclerosis (ALS). Modulation of miR-218 dose causes threshold-like neuromuscular synaptogenesis and mouse viability phenotypes and revealed heterogenous dose-response curves of target mRNA repression. A dose-response network analyses unmasked a specific regulon exhibiting an inflection point in repression concomitant with the emergence of motor phenotypes. Furthermore, we find that miR-218 indirectly activates a coherent peripheral neuronal genetic signature and that the magnitude of miR-218 mediated effects varies in distinct motor subpopulations. This work reveals miRNA dose as a potent, non-linear modulator of in vivo mRNA target selection, suggesting how cellular dysfunction might abruptly arise when miRNA levels fall below a critical threshold. For the data uploaded here, motor neurons carrying an Hb9:gfp reporter were FACS isolated based upon GFP expression and used for either bulk or single cell RNA sequencing (10x genomics). Motor neurons were either mouse embryonic stem cell derived motor neurons (ESMNs) or mouse motor neurons from developmental stage E12. ESMN samples carry unique mutations of the miR-218-2 promoter of distinct sizes, or are wild type. E12 motor neurons carry combinations of mutations to either miR-218-1 or miR-218-2 or the promoter for miR-218-2. For single cell RNA sequencing, we have WT and miR-218 double knockout (DKO) motor neurons in duplicate. We also sequenced 4 samples of dorsal root ganglia from E12 mice (DRG1-4).
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.