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.
Project description:The inner ear in mammals is derived from a simple ectodermal thickening called the otic placode. Through a series of complex morphological changes, the placode forms the mature inner ear comprising of the auditory organ (cochlea) and the vestibular/balance organs (utricle, saccule, and three semi-circular canals). The vast majority of genes known to be involved during inner ear development have been found through mutational screens or by chance. To identify genes that can serve as novel candidates required for inner ear development, and also candidate genes for uncloned human deafnesses, inner ear tissues from mouse embryos from E9 to E15 were microdissected and expression-profiled at half-day intervals. Also profiled was the non-inner ear mesenchymal tissue surrounding the inner ear tissue. Various patterns of gene expression were identified, and significant biological pathways that these genes represented were identified. Also identified were mouse genes whose human orthologs are located within uncloned non-syndromic deafness intervals, thus serving as candidates for sequence analysis. Experiment Overall Design: Inner ear tissues from E9 to E15 were microdissected at half-day intervals. E9 is the earliest stage when the otic placode is clearly visible and able to be microdissected cleanly. E15 is the stage when all the organs of the inner ear have become established, as have the sensory hair and non-sensory support cells within those organs. For each of the stages from E9 to E10, whole inner ears were profiled. For each of the stages from E10.5 to E12, the primordial cochlear and vestibular organs were profiled separately. For each of the stages from E12.5 to E15, the cochlea and the saccule were profiled separately, whereas the utricle and the three ampullae were combined and profiled together. Any given tissue from any given stage was a collection of anywhere between 4 to 17 identical tissues, and was obtained in duplicate (i.e. from different litters). Hence, a total of 58 inner ear samples were obtained. Moreover, non-inner ear tissue found in the immediate vicinity of inner ear tissue was also obtained and profiled. Specifically, all non-inner ear tissue from E9 was profiled in duplicate. Non-inner ear tissue from E9.5 to E10.5 was pooled and profiled together (in duplicate), whereas that from E11 to E15 was pooled and profiled together (also in duplicate). Therefore, a total of 6 non-inner samples were obtained.
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from Mus musculus tissues (Heart, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from seven Mus musculus tissues (Heart, Brain, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
Project description:Meis genes have been shown to control essential processes during development of the central and peripheral nervous system. Here we have defined the roles of the Meis2 gene during vertebrate inner ear induction and the formation of the cochlea. Meis2 is expressed in several tissues required for inner ear induction and in non-sensory tissue of the cochlear duct. Global inactivation of Meis2 in the mouse leads to a severely reduced size of the otic vesicle. Tissue-specific knock outs of Meis2 reveal that its expression in the hindbrain is essential for inner ear induction. Inactivation of Meis2 in the inner ear itself leads to an aberrant coiling of the cochlear duct. By analyzing transcriptomes obtained from Meis2 mutants and ChIPseq analysis of an otic cell line we define candidate target genes for Meis2 which may be directly or indirectly involved in cochlear morphogenesis. Taken together, these data show that Meis2 is essential for inner ear formation and provide an entry point to unveil the network underlying proper coiling of the cochlear duct.
Project description:The inner ear in mammals is derived from a simple ectodermal thickening called the otic placode. Through a series of complex morphological changes, the placode forms the mature inner ear comprising of the auditory organ (cochlea) and the vestibular/balance organs (utricle, saccule, and three semi-circular canals). The vast majority of genes known to be involved during inner ear development have been found through mutational screens or by chance. To identify genes that can serve as novel candidates required for inner ear development, and also candidate genes for uncloned human deafnesses, inner ear tissues from mouse embryos from E9 to E15 were microdissected and expression-profiled at half-day intervals. Also profiled was the non-inner ear mesenchymal tissue surrounding the inner ear tissue. Various patterns of gene expression were identified, and significant biological pathways that these genes represented were identified. Also identified were mouse genes whose human orthologs are located within uncloned non-syndromic deafness intervals, thus serving as candidates for sequence analysis. Keywords: Developmental timecourse