Does the novel Syk inhibitor R406 reveal mechanistic differences in the initiation of GPVI and CLEC-2 signaling in platelets?
The inhibitory effect of R406 provides direct evidence of a role for Syk in GPVI, CLEC-2 and integrin alphaIIbbeta3 signaling in human platelets. Further, the results demonstrate a critical role for Syk in mediating tyrosine phosphorylation of CLEC-2, suggesting a novel model in which both Src and Syk kinases regulate tyrosine phosphorylation of the C-type lectin receptor leading to platelet activation.
Rhizobitoxine-induced chlorosis occurs in coincidence with methionine deficiency as a result of cystathione-beta-lyase inhibition during methionine biosynthesis.