StAR-related lipid transfer domain protein 8 (STARD8) also known as deleted in liver cancer 3 protein (DLC-3) is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

that in humans is encoded by the ''STARD8''

gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...

and is a member of the DLC family.

Structure and function

The protein is 1103 amino acids long, which like other DLC proteins consists of a sterile alpha motif (SAM),

RhoGAP RhoGAP domain is an evolutionary conserved protein domain of GTPase activating proteins towards Rho/ Rac/ Cdc42-like small GTPases. Human proteins containing this domain ABR; ARHGAP1; ARHGAP10; ARHGAP11A; ARHGAP11B; ARHGAP12; AR ...

and a StAR-related lipid-transfer (START) domains. The protein is a Rho GTPase-activating protein (GAP), a type of protein that regulates members of the

Rho family of GTPases The Rho family of GTPases is a family of small (~21 kDa) signaling G proteins, and is a subfamily of the Ras superfamily. The members of the Rho GTPase family have been shown to regulate many aspects of intracellular actin dynamics, and are foun ...

. STARD8 is characterized as activating

Rho GTPases Rho GTPase may refer to: *Any member of the Rho family of GTPases *The members of the Rho family of GTPases belonging to the '' Rho subclass'' *RHOA Transforming protein RhoA, also known as Ras homolog family member A (RhoA), is a small GTPase ...

. Its expression inhibits the growth of human breast and prostate cancer cells in culture.

Tissue distribution and pathology

The protein is expressed in tissues throughout the body, but is absent or reduced in many kinds of

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

cells. While there are no known disorders caused by STARD8, partial loss of the ''STARD8'' gene occurs in cases of craniofrontonasal syndrome where the

EFNB1 Ephrin B1 is a protein that in humans is encoded by the ''EFNB1'' gene. It is a member of the ephrin family. The encoded protein is a type I membrane protein and a ligand of Eph-related receptor tyrosine kinases. It may play a role in cell adhes ...

gene (which causes the syndrome) is completely deleted.

Structure and function

Tissue distribution and pathology

References

Further reading