Different large deletions of T cell receptor V beta genes in natural populations of mice.
A panel of geographically separate Mus m. domesticus and Swiss mice from several sources was screened for deletions in the T cell receptor variable (V) beta locus. Four out of forty-three strains tested show a deletion identical to or larger than the deletion previously described in SJL mice. To our knowledge, this is the first time that such important V beta deletions are described in inbred or partially inbred wild-derived strains of mice. On the other hand there seems to be very little polymorphism between the remaining V beta genes. Expression of V beta genes in peripheral and intra-thymic T cells was tested using antibodies specific for different V beta polypeptide chains. Flow cytometry analysis revealed a high expression of V beta 6 and V beta 17 genes in the Copacabana Swiss-derived strain and an absence of V beta 17 expression in the WLA wild-derived strain. The three Mus m. domesticus strains (WLA, DDO and WBG) having deleted two to three additional V beta subfamilies compared to SJL present no apparent immune deficiencies or autoimmune disorders. We conclude that relatively few V beta genes may suffice for unimpaired survival of wild mice and that there is a selective pressure for the structural conservation of the remaining V beta genes.
Jouvin-Marche
E
E
Immunochimie Analytique, Institut Pasteur, Paris, France.
Trede
N S
NS
Bandeira
A
A
Tomas
A
A
Loh
D Y
DY
Cazenave
P A
PA
D000818:Animals; D002872:Chromosome Deletion; D005434:Flow Cytometry; D015870:Gene Expression; D051379:Mice / Q000235:genetics*; D008807:Mice, Inbred BALB C; D012150:Polymorphism, Restriction Fragment Length; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*
D011948:Receptors, Antigen, T-Cell