STARD13

StAR-related lipid transfer domain protein 13 (STARD13) also known as deleted in liver cancer 2 protein (DLC-2) is a protein that in humans is encoded by the STARD13 gene and a member of the DLC family of proteins.

Function and structure
STARD13 serves as a Rho GTPase-activating protein (GAP), a type of protein that regulates members of the Rho family of GTPases. It selectively activates RhoA and CDC42 and suppresses cell growth by inhibiting actin stress fiber assembly.

The protein consists of an N-terminal sterile alpha motif (SAM) domain, a serine-rich domain, a RhoGAP domain and at the C-terminus, a StAR-related lipid-transfer domain (START).

Tissue distribution and pathology
The protein was identified in part through its differential expression in cancers. A low level of STARD13 was observed in less differentiated hepatocellular carcinoma tissue with higher RhoA expression. A small patient study finds that the absence of STARD13 in hepatocellular carcinomas correlates with higher levels of RhoA and a poorer prognosis than patients with carcinomas that were STARD13-positive.