Cd309

Acronym for Cluster of differentiation 309.

CD 309 refers to the kinase insert domain receptor (KDR); it is also known as FLK1, VEGFR, VEGFR2 and belongs to the subtypes of VEGFR. VEGF receptors are receptors for vascular endothelial growth factor (VEGF). There are three main subtypes of VEGFR, VEGFR 1, 2 and 3.

VEGF receptors have an extracellular portion consisting of 7 immunoglobulin-like domains, a single transmembrane spanning region, and an intracellular portion containing a cleaved tyrosine kinase domain. VEGF-A binds to VEGFR-1 (Flt-1) and VEGFR-2 (KDR / Flk-1). VEGFR-2 appears to mediate almost all known cellular responses to VEGF. The function of VEGFR-1 is less well defined, although it is thought to modulate VEGFR-2 signaling. In addition, VEGFR2 may interact with the extracellular Tat protein HIV-1 upon VEGF activation and appears to enhance angiogenesis in Kaposi's sarcoma lesions.