A receptor surface Ig (sIg) signaling variant of WEHI-231 was constructed to investigate components and linkages between various signaling events associated with signal transduction through sIg. Unlike the wildtype, crosslinking of sIgM on VS2.12-cl.2 did not result in downregulation of proliferation. Similarly, receptor crosslinking was uncoupled from inositol phospholipid (PI) hydrolysis and upregulation of c-fos expression in the variant. The signaling defect in VS2.12-cl.2 appears to be proximal to phospholipase C activation as direct G protein activation by A1F4- triggers PI hydrolysis and bypassing PI hydrolysis using phorbol diester stimulation of protein kinase C restores the inhibitable phenotype and the ability to upregulate c-fos. Even more interesting, sIg-linked Ca2+ responses by VS2.12-cl.2 are equivalent to these observed in the wildtype WEHI-231. These latter results suggest that contrary to current thought, sIg-generated signals may not be coupled to Ca2+ fluxes entirely via inositol phospholipid hydrolysis. Thus, VS2.12-cl.2 is a new and powerful tool with which to analyze signaling through sIg at the molecular level.
Isolation and characterization of a B lymphocyte mutant with altered signal transduction through its antigen receptor.
- Views Icon Views
- PDF LinkPDF
- Share Icon Share
- Tools Icon Tools
- Search Site
J G Monroe, V L Seyfert, C S Owen, N Sykes; Isolation and characterization of a B lymphocyte mutant with altered signal transduction through its antigen receptor.. J Exp Med 1 March 1989; 169 (3): 1059–1070. doi: https://doi.org/10.1084/jem.169.3.1059
Download citation file: