Variable spread of X inactivation affecting the expression of different epitopes of the Hya gene product in mouse B-cell clones.
Cloned B-cell lines from a female T16H/XSxr mouse in which Tdy expression was suppressed due to X inactivation and from a male X/XSxr mouse, both of the (kxb)F1 haplotype, were examined for H-Y expression. This was determined both by their ability to act as targets for H-2k and H-2b-restricted H-Y-specific cytotoxic T cells and by their ability to stimulate the proliferation of H-2Kk, H-2Db (class I) and Ab (class II)-restricted T-cell clones. In B-cell clones from the T16H/XSxr mouse, expression of H-Y/Db exhibited partial X inactivation and only a proportion (congruent to 30%) of the cells were targets for or stimulated H-2Db-restricted H-Y-specific T cells. In contrast, H-Y epitopes restricted by H-2k (H-Y/Kk, H-Y/Dk) and Ab (H-Y/Ab) exhibited no X inactivation. Furthermore, no inactivation of H-Y/Db, H-Y/Ab, or H-Yk was observed in the male X/XSxr mouse. These results indicate that the T16H/XSxr female is a mosaic, as a result of the variable spread of X inactivation into the Sxr region. They further suggest that the H-Y antigen recognized in association with H-2k and H-2Db class I molecules and Ab class II molecules may be the product of more than one gene.
Scott
D
D
Transplantation Biology, Clinical Research Centre, Harrow, Middlesex, England.
McLaren
A
A
Dyson
J
J
Simpson
E
E
D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism; D015139:Blotting, Southern; D001853:Bone Marrow; D002461:Cell Line, Transformed; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D004303:Dosage Compensation, Genetic; D005260:Female; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006183:H-2 Antigens / Q000502:physiology; D006182:H-Y Antigen / Q000096:biosynthesis / Q000235:genetics*; D064532:Histocompatibility Antigen H-2D; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA
D006183:H-2 Antigens; D006182:H-Y Antigen; D064532:Histocompatibility Antigen H-2D