Sequence and characterization of the Ig heavy chain constant and partial variable region of the mouse strain 129S1.
Although the entire mouse genome has been sequenced, there remain challenges concerning the elucidation of particular complex and polymorphic genomic loci. In the murine Igh locus, different haplotypes exist in different inbred mouse strains. For example, the Igh(b) haplotype sequence of the Mouse Genome Project strain C57BL/6 differs considerably from the Igh(a) haplotype of BALB/c, which has been widely used in the analyses of Ab responses. We have sequenced and annotated the 3' half of the Igh(a) locus of 129S1/SvImJ, covering the C(H) region and approximately half of the V(H) region. This sequence comprises 128 V(H) genes, of which 49 are judged to be functional. The comparison of the Igh(a) sequence with the homologous Igh(b) region from C57BL/6 revealed two major expansions in the germline repertoire of Igh(a). In addition, we found smaller haplotype-specific differences like the duplication of five V(H) genes in the Igh(a) locus. We generated a V(H) allele table by comparing the individual V(H) genes of both haplotypes. Surprisingly, the number and position of D(H) genes in the 129S1 strain differs not only from the sequence of C57BL/6 but also from the map published for BALB/c. Taken together, the contiguous genomic sequence of the 3' part of the Igh(a) locus allows a detailed view of the recent evolution of this highly dynamic locus in the mouse.
Department of Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
Ida
I
Retter
Christophe
C
Chevillard
Maren
M
Scharfe
Ansgar
A
Conrad
Martin
M
Hafner
Tschong-Hun
TH
Im
Monika
M
Ludewig
Gabriele
G
Nordsiek
Simone
S
Severitt
Stephanie
S
Thies
America
A
Mauhar
Helmut
H
Blöcker
Werner
W
Müller
Roy
R
Riblet
D000483:Alleles; D000818:Animals; D019143:Evolution, Molecular; D020440:Gene Duplication; D016678:Genome / Q000276:immunology; D006239:Haplotypes / Q000235:genetics / Q000276:immunology; D007127:Immunoglobulin Constant Regions / Q000235:genetics* / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000235:genetics* / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000235:genetics* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D040641:Quantitative Trait Loci / Q000235:genetics / Q000276:immunology*; D013045:Species Specificity
D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region