Project description:Haploid stem cells offer an easy-to-manipulate genetic system and therefore have great values for studies of recessive phenotypes. Here, we show that mouse androgenetic haploid ES (ahES) cell lines can be established by transferring sperm into enucleated oocyte. The ahES cells maintain haploidy and stable growth over 30 passages, express pluripotent markers, possess the ability to differentiate into all three germ-layers in vitro and in vivo, and contribute to germline of chimeras when injected into blastocysts. Although epigenetically distinct from sperm cells, the ahES cells can produce viable and fertile progenies after intracytoplasmic injection into mature oocytes. The oocyte injection procedure can also produce viable transgenic mice from genetically engineered ahES cells. We used microarrays to compare the global programme of gene expression among ahES cells, normal diploid ES cells, MEF cells and round sperm cells and found that gene expression pattern of ahES cells was highly similar with ES cells but was distinct from MEF cells and round sperms. Androgenetic haploid ES cells were FACS sorted to harvest the G0/G1 phase haploid cells. Total RNA were extracted from three ahES cell lines (AH129-5, AH129-N1, AH129-NC1, all 129Sv genetic background), two ES cell lines ( CS1-1, R1, 129Sv background), MEF cells and round sperm and hybridized with Affymetrix GeneChip 430 2.0 array. Data were collected and analyzed to compare their gene expression pattern.
Project description:Haploid stem cells offer an easy-to-manipulate genetic system and therefore have great values for studies of recessive phenotypes. Here, we show that mouse androgenetic haploid ES (ahES) cell lines can be established by transferring sperm into enucleated oocyte. The ahES cells maintain haploidy and stable growth over 30 passages, express pluripotent markers, possess the ability to differentiate into all three germ-layers in vitro and in vivo, and contribute to germline of chimeras when injected into blastocysts. Although epigenetically distinct from sperm cells, the ahES cells can produce viable and fertile progenies after intracytoplasmic injection into mature oocytes. The oocyte injection procedure can also produce viable transgenic mice from genetically engineered ahES cells. We used microarrays to compare the global programme of gene expression among ahES cells, normal diploid ES cells, MEF cells and round sperm cells and found that gene expression pattern of ahES cells was highly similar with ES cells but was distinct from MEF cells and round sperms.
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.
Project description:Nucleolus-associated DNA was isolated from MEF cells before and after conditional knock-out of UBF and hybridized against genomic DNA in biological replicates. Two different types of immortalized MEF cells were used. MEFs were immortalized by genetic depletion of p53, iMEFs were immortalized by transfection of the SV40 Tt antigen.