journal article
LitStream Collection
Home
Coy, J.; Kioschis, P.; Sedlacek, Z.; Poustka, A.
doi: 10.1007/BF00352342pmid: 8199400
As a part of the functional analysis of the region from the position of the fragile X mutation to the telomere of the long arm of the human X Chromosome (Chr), we have developed a number of different approaches to identify genes located in this area. We describe here a procedure allowing the rapid identification of expressed sequences based on the hybridization of radioactively labeled complex cDNA probes derived from different pig and human tissues to cosmid clones gridded onto nylon filters and to restriction fragments of these clones. This technique has allowed the identification of a number of differentially expressed sequences in cosmid clones covering most of the Xq27.3 to Xqter region. Using these sequences as hybridization probes, cDNA clones for new genes expressed in a tissue-specific manner were isolated. Applied to genomic regions defined by overlapping cosmid clones, this method will serve as a major component in our strategy to establish integrated physical and transcription maps.
Schmutz, S.; Berryere, T.; Moker, J.; Thue, T.; Winkelman, D.
doi: 10.1007/BF00352343pmid: 8199401
Bovine gene mapping is progressing rapidly using syntenic group mapping based on somatic cell hybrids and linkage, and to a lesser extent on in situ hybridization. Single chromosome DNA libraries are a logical next step, and this was, therefore, the aim of our laboratory. Since we have access to several cattle with t(1;29) and this chromosome is readily distinguishable, we chose this as our first target—recognizing that we would not produce a “single” chromosome library in the strict sense because two autosomes are represented. We utilized an inverted microscope and a micromanipulator fitted with glass instruments pulled specifically to dissect off approximately 100 t(1:29) chromosomes per microdrop. A glass chamber made to accommodate a hanging drop was used to extract the DNA under a dissecting microscope. The DNA was then cleaved with EcoRI and inserted in λgtwes arms. Host cells were then infected with these phage and positive clones obtained. The first clone, isolated from this library by hybridization with a human collagen 6A1 cDNA, was mapped by in situ hybridization to bovine Chromosome (Chr) 1q12–q14, near the centromere. The second clone, an anonymous DNA fragment (D1S11), was mapped to 1q43–q46, near the terminal end.
Jiang, X.; Villeneuve, L.; Turmel, C.; Kozak, C.; Jolicoeur, P.
doi: 10.1007/BF00352344pmid: 7911043
Ahi-1 has previously been identified as a common helper provirus integration site on mouse Chromosome (Chr) 10 in 16% of Abelson pre-B-cell lymphomas and shown to be closely linked to the Myb protooncogene. By using long-range restriction mapping, we have mapped the Myb and Ahi-1 regions within a 120-kbp DNA fragment. The Ahi-1 region is located approximately 35 kbp downstream of the Myb gene. A further comfirmation of this finding was obtained by screening a mouse YAC library. The three positive clones obtained contained both the Myb and Ahi-1 gene sequences. To test whether provirus integration in the Ahi-1 region enhances the expression of Myb by a cis-acting mechanism, we have also examined Myb gene expression in A-MuLV-induced pre-B-lymphomas. Our data have revealed that there is no clear evidence for such activation in the tumors we have tested, indicating that provirus insertion in the Ahi-1 region is activating a novel gene, apparently involved in tumor formation.
Trudel, M.; Chrétien, N.; D'Agati, V.
doi: 10.1007/BF00352345pmid: 8199402
Nineteen SBM transgenic mouse lines specifically expressing the c-myc protooncogene in renal epithelium have developed polycystic kidney disease (PKD). Transgene expression is completely penetrant, leading to death from renal failure. In the course of continuous breeding of eight transgenic lines, all lines underwent spontaneous transgene mutations characterized by partial deletion and probable rearrangement of the transgene insert. Revertant mice and their progeny have no evidence of renal disease. This constitutes the first report of spontaneous mutations occurring within transgene inserts. The high spontaneous mutation frequency of 10-2 to 10-3 greatly exceeds that of naturally occurring mutations and is probably favored by the transgene's multiple tandem insertion. These spontaneous mutations demonstrate that the intact transgene is necessary and sufficient to produce the SBM phenotype. Further, these results implicate deregulation of factor(s) governing epithelial cell proliferation in the pathogenesis of PKD in SBM mice.
Szpirer, C.; Szpirer, J.; Rivière, M.; Levan, G.; Orlowski, J.
doi: 10.1007/BF00352346pmid: 8199403
The plasma membrane Na/H exchanger plays an essential role in regulating intracellular pH and Na+ concentration and has been implicated in several pathophysiological conditions, including essential hypertension and congenital secretory diarrhea. Four isoforms of the Na/H exchanger encoded by separate genes have recently been identified by cDNA cloning. To map their locations in the human and rat genomes, rat isoform-specific cDNA probes were hybridized to Southern filters containing panels of somatic cell hybrids that segregate either human or rat chromosomes. The rat Nhe1 gene was assigned to Chromosome (Chr) 5, extending the homology with human chromosome 1p that has previously been shown to contain the human NHE1 gene. The genes encoding the NHE-2 and NHE-4 isoforms were syntenic in the two species and assigned to rat Chr 9 and human Chr 2. A single Nhe3 gene was detected in rat and assigned to Chr 1. In contrast, although evidence to date has suggested a single human NHE3 gene on Chr 5, two NHE3 genes, NHE3A and NHE3B, were identified and assigned to Chrs 10 and 5, respectively. Interestingly, rat Chr 1 has recently been found to carry a gene controlling systolic blood pressure upon sodium loading in stroke-prone, spontaneously hypertensive rats. Thus, this and other evidence implicates rat Nhe3 as a possible candidate gene in this disease process.
Lengeling, A.; Zimmer, W.; Goodman, S.; Ma, Y.; Bloom, M.; Bruneau, G.; Krieger, M.; Thibault, J.; Kaupmann, K.; Jockusch, H.
doi: 10.1007/BF00352348pmid: 8199405
Showing 1 to 10 of 18 Articles