Structural relationships among the H-2 D-regions of murine MHC haplotypes.
The number of genes encoding functional Ag-presenting molecules in the D region of the murine MHC differs among haplotypes. For example, the H-2b D region contains a single "D/L" gene, H-2Db, whereas the d-haplotype encodes two, H-2Dd and Ld. Using D/L specific oligonucleotide probes, we have found that, as with H-2d, the q- and v-haplotypes contain two D/L genes, whereas the other haplotype examined have one. Hybridization analysis using cloned probes that map between H-2Dd and Ld revealed similar structures in each of the three haplotypes (d, q, and v) which have "duplicated" D regions. Two approaches were used to examine allelic relationships among the D/L genes. First, the 5' region of the H-2Db gene was sequenced, and found to be more similar to H-2Ld than to H-2Dd. Second, oligonucleotide probes that distinguish H-2Ld from H-2Dd revealed H-2Ld-related genes in several haplotypes, including the duplicated haplotypes H-2q and H-2v. Analogous probes specific for H-2Dd, however, did not detect similar sequences in the other haplotypes. We interpret these results to mean that the three duplicated D regions arose from a common duplication event, and share the five gene structure of the D region cluster defined in H-2d. However, subsequent events have generated sequence divergence at the D-locus.
Duran
L W
LW
Department of Immunology, Mayo Clinic, Rochester, MN 55905.
Horton
R M
RM
Birschbach
C W
CW
Chang-Miller
A
A
Pease
L R
LR
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D000830:Animals, Laboratory; D001483:Base Sequence; D003434:Crossing Over, Genetic; D005805:Genes, MHC Class I; D006183:H-2 Antigens / Q000235:genetics* / Q000302:isolation & purification; D006239:Haplotypes; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D005810:Multigene Family; D015345:Oligonucleotide Probes
D006183:H-2 Antigens; D015345:Oligonucleotide Probes