STARD13 explained

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.^{[1] [2]}

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.^[3] It selectively activates RhoA and CDC42 and suppresses cell growth by inhibiting actin stress fiber assembly.^[3]

The protein consists of an N-terminal sterile alpha motif (SAM) domain,^[4] 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.^[5]

Further reading

• Ching YP, Wong CM, Chan SF, Leung TH, Ng DC, Jin DY, Ng IO . Deleted in liver cancer (DLC) 2 encodes a RhoGAP protein with growth suppressor function and is underexpressed in hepatocellular carcinoma . The Journal of Biological Chemistry . 278 . 12 . 10824–30 . March 2003 . 12531887 . 10.1074/jbc.M208310200 . free .
• Day CL, Puthalakath H, Skea G, Strasser A, Barsukov I, Lian LY, Huang DC, Hinds MG . Localization of dynein light chains 1 and 2 and their pro-apoptotic ligands . The Biochemical Journal . 377 . Pt 3 . 597–605 . February 2004 . 14561217 . 1223895 . 10.1042/BJ20031251 .
• Nagaraja GM, Kandpal RP . Chromosome 13q12 encoded Rho GTPase activating protein suppresses growth of breast carcinoma cells, and yeast two-hybrid screen shows its interaction with several proteins . Biochemical and Biophysical Research Communications . 313 . 3 . 654–65 . January 2004 . 14697242 . 10.1016/j.bbrc.2003.12.001 .
• Colland F, Jacq X, Trouplin V, Mougin C, Groizeleau C, Hamburger A, Meil A, Wojcik J, Legrain P, Gauthier JM . Functional proteomics mapping of a human signaling pathway . Genome Research . 14 . 7 . 1324–32 . July 2004 . 15231748 . 442148 . 10.1101/gr.2334104 .
• Leung TH, Ching YP, Yam JW, Wong CM, Yau TO, Jin DY, Ng IO . Deleted in liver cancer 2 (DLC2) suppresses cell transformation by means of inhibition of RhoA activity . Proceedings of the National Academy of Sciences of the United States of America . 102 . 42 . 15207–12 . October 2005 . 16217026 . 1250229 . 10.1073/pnas.0504501102 . 2005PNAS..10215207L . free .

Notes and References

1. Couch FJ, Rommens JM, Neuhausen SL, Bélanger C, Dumont M, Abel K, Bell R, Berry S, Bogden R, Cannon-Albright L, Farid L, Frye C, Hattier T, Janecki T, Jiang P, Kehrer R, Leblanc JF, McArthur-Morrison J, Meney D, Miki Y, Peng Y, Samson C, Schroeder M, Snyder SC, Simard J . Generation of an integrated transcription map of the BRCA2 region on chromosome 13q12-q13 . Genomics . 36 . 1 . 86–99 . August 1996 . 8812419 . 10.1006/geno.1996.0428 . free .
2. Web site: Entrez Gene: STARD13 START domain containing 13.
3. Ching YP, Wong CM, Chan SF, Leung TH, Ng DC, Jin DY, Ng IO . Deleted in liver cancer (DLC) 2 encodes a RhoGAP protein with growth suppressor function and is underexpressed in hepatocellular carcinoma . The Journal of Biological Chemistry . 278 . 12 . 10824–30 . March 2003 . 12531887 . 10.1074/jbc.M208310200 . free .
4. Li. Hongyan. Fung. King-Leung. Jin. Dong-Yan. Chung. Stephen S. M.. Ching. Yick-Pang. Ng. Irene Oi-lin. Sze. Kong-Hung. Ko. Ben C. B.. Sun. Hongzhe. 2007-06-01. Solution structures, dynamics, and lipid-binding of the sterile alpha-motif domain of the deleted in liver cancer 2. Proteins. 67. 4. 1154–1166. 10.1002/prot.21361. 1097-0134. 17380510. 20407564.
5. Xiaorong L, Wei W, Liyuan Q, Kaiyan Y . Underexpression of deleted in liver cancer 2 (DLC2) is associated with overexpression of RhoA and poor prognosis in hepatocellular carcinoma . BMC Cancer . 8 . 205 . 2008 . 18651974 . 2496915 . 10.1186/1471-2407-8-205 . free .