Novel signaling pathway suggested by SH3 domain-mediated p95vav/heterogeneous ribonucleoprotein K interaction.

The role of the protooncogene product p95vav in signal transduction was investigated by characterizing its interactions with proteins that may represent components of a novel signaling pathway. We demonstrate here stable association of p95vav with the heterogeneous ribonucleoprotein K (hnRNP-K), a protein that not only was found to be part of hnRNP particles but has also been implicated in transcriptional regulation of the c-myc gene. Through the PLPPPPPPRG sequence, hnRNP-K specifically interacts with the SH3 domain of p95vav and thus represents a novel SH3 binding protein that may be capable of translating cell surface receptor signals through p95vav activation into regulatory events on the level of gene expression.