| First Author | Bennett K | Year | 1981 |
| Journal | Mouse News Lett | Volume | 64 |
| Pages | 89 | Mgi Jnum | J:20226 |
| Mgi Id | MGI:68334 | Citation | Bennett K, et al. (1981) Chromosomal locations of middle repetitive DNA families. Mouse News Lett 64:89 |
| abstractText | Full text of MNL contribution: Chromosomal locations of middle repetitive DNA families. We are interested in the chromosomal locations of several families of middle repetitive DNA. These include sets of families chosen at random from the mouse genome and the family of 15-20 genes coding for the major urinary proteins (mup). Mup-a, a regulatory locus, has been mapped to chromosome 4, but the structural genes are unmapped, as no variants have been reported. The chromosomal organization of middle repetitive DNA is unknown. We are asking if a particular family is dispersed throughout the genome or clustered onto one or several chromosomes. This knowledge is pertinent to postulated regulatory functions and, for mup, to cis or trans regulatory control. The techniques we are using include in situ hybridization to metaphase chromosomes and Southern blot analysis of DNAfrom Chinese hamster; mouse hybrids and recombinant inbred (RI) lines. The molecular probes are derived from genomic clones of middle repetitive DNA (see abstract, D. Pietras) and from our cDNA mup clones (R. Barth). Our present in situ results indicate that a particular highly repeated DNA family is found on all chromosomes. The addition of 10% dextran sulfate greatly enhances the signal obtained with in situ hybridization Use of parentals of Chinese hamster: mouse lines in Southern blot analysis has shown that several of the highly repeated families are indistinguishable between species; while several lower repeat families (including mup) give mouse specific banding patterns. Using somatic cell hybrid lines of Chinese hamster: mouse obtained from Dr. Peter Lalley at Oak Ridge, we have seen that only the hamster pattern is retained in those lines which have lost mouse chromosome 4. Those lines which have not segregated out chromosome 4 still display the mouse mup pattern. Thus all the structural genes for mup map to chromosome 4. For more precise mapping of the multiple mup genes, we have used RI lines. Selected progenitors give 2 different banding patterns with polymorphism in 5-6 of the 15 bands seen in the Southern pattern. With the CXB and AKXL lines we find complete concordance of our cloned structural probe with the strain distribution pattern for the mup a regulatory locus. K. BENETT, D. PIETRAS; R. BARTH and N. HASTIE |
