Project description:The ability to generate defined null mutations in mice revolutionized the analysis of gene function in mammals. However, gene-deficient mice generated by using 129-derived embryonic stem (ES) cells may carry large segments of 129 DNA, even when extensively backcrossed to reference strains, such as C57BL/6J, and this may confound interpretation of experiments performed in these mice. Tissue plasminogen activator (tPA), encoded by the PLAT gene, is a fibrinolytic serine protease that is widely expressed in the brain. A large number of neurological abnormalities have been reported in tPA-deficient mice. The studies here compare genes differentially expressed in the brains of Plat-/- mice from two independent Plat-/- mouse derivations to wild-type C57BL/6J mice. One strain denoted “Old” was constructed in ES cells from a 129 mouse and backcrossed extensively to C57BL/6J, and one denoted “New” Plat-/- mouse was constructed using zinc finger nucleases directly in the C57BL/6J-Plat-/- mouse strain. We identify a significant set of genes that are differentially expressed in the brains of Old Plat-/- mice that preferentially cluster in the vicinity of Plat on chromosome 8, apparently linked to more than 20 Mbp of DNA flanking Plat being of 129 origin. No such clustering is seen in the New Plat-/- mice.
Project description:Proteome isolated from C57BL/6J mouse B and T cells are evluated for the presence of novel open reading frame products (nORFs). Translation products encoded by non canonical or novel open reading frame (ORF) genomic regions are generally considered too small to play any significant biological role, and dismissed as inconsequential. We conduct a systematic study of novel ORFs to gain new insights into normal biological and disease processes.
Project description:A M. tuberculosis transposon library was used to infect WT and iNOS-/- mice. Surviving mutants were recovered from spleens, genomic DNA was extracted, and labeled probes were synthesized from transposon ends. Probes from each WT mouse were hybridized with probes from a similar iNOS-/- mouse.
