Adapter molecule crk

Crk (adapter molecule crk, encoded by CRK) is a 304-residue adaptor protein that mediates cell signaling through interactions with multiple partners including BCAR1, RAPGEF1, DOCK1, and DOCK4 (UniProt: P46108). It promotes cell branching, adhesion, spreading, and migration by regulating RAP1 activation and Rac-dependent cytoskeletal responses, and participates in phagocytosis of apoptotic cells and MAPK8-dependent signaling.

Crk operates in the context of cell adhesion and motility pathways, with potential roles in ephrin-mediated signaling via EFNA5-EPHA3 interactions. No disease associations are documented in the UniProt entry.

In Alzheimer's disease, Crk is significantly upregulated in post-mortem AD brain tissue compared to age-matched controls, with a mean log2 fold-change of +0.92 across subcellular fractions (Chaparral AD proteomics). This elevation suggests a potential involvement in AD-related pathology, though the functional consequence of increased Crk expression in the diseased brain remains to be determined.