Examination of B lymphoid cell lines for membrane immunoglobulin-stimulated tyrosine phosphorylation and src-family tyrosine kinase mRNA expression.

摘要: Crosslinking of membrane immunoglobulin (mIg) on B cells induces two signal transduction pathways: protein tyrosine phosphorylation and phosphoinositide turnover. A panel murine human cell-lines, representing different stages cell development, was examined for the presence anti-immunoglobulin-induced phosphorylation. Of 10 lines examined, only one, Raji line, had no detectably induced The pattern proteins that were phosphorylated in response to mIg crosslinking differed somewhat development. Differences levels constitutive also observed between lines. The identity kinase(s) activated by ligation is not known. However, members srcit family intracellular kinases have been implicated as molecules. As a general phenomenon immunoglobulin, it might be expected present all which signalling occurs. Therefore we these expression mRNAs encoding eight known src-like kinases. Surprisingly, kinase expressed at least some examined. fyn, hck, lck genes suggests may developmentally regulated lineage. Three kinases, p55blk, p53/p56lyn p60src, detected lines. Whereas src gene shows ubiquitous expression, blk lyn mostly restricted hematopoietic origin, more especially lymphoid cells. Thus, p55blk particularly good candidates immunoglobulin-activated kinase.