DIRAS3
Description
The DIRAS3 (DIRAS family GTPase 3) is a protein-coding gene located on chromosome 1.
DIRAS3, also known as ARHI (Aplysia ras homology member I), is a protein encoded by the DIRAS3 gene in humans. It belongs to the Ras superfamily and is expressed in normal ovarian and breast epithelial cells, but not in ovarian and breast cancers. DIRAS3 is a maternally imprinted gene, with monoallelic expression of the paternal allele. This imprinting pattern is linked to growth suppression, suggesting that DIRAS3 acts as a tumor suppressor gene. The loss of DIRAS3 function appears to be a key factor in the development of ovarian and breast cancers. DIRAS3 is a 26-kDa protein encoded by a gene with one promoter, two exons, and one intron. Despite structural similarities to other GTPase proteins, DIRAS3's function is significantly different from Ras. While Ras promotes cell growth, DIRAS3 acts as a tumor suppressor. DIRAS3 shares 50–60% homology with Ras and Rap, other small GTP-binding proteins. Reduced expression of DIRAS3 has been observed in approximately 70% of invasive breast cancers.
DIRAS3, also known as ARHI (Aplysia ras homology member I), is a GTPase protein belonging to the Ras superfamily. It exhibits distinct functional characteristics compared to the typical oncogenic Ras proteins. While Ras promotes cellular proliferation and signaling, DIRAS3 acts as a tumor suppressor gene. Notably, DIRAS3 is expressed in normal ovarian and breast epithelial cells but its expression is significantly reduced or absent in ovarian and breast cancers. The loss of DIRAS3 function is associated with tumor growth and progression. This suggests that DIRAS3 plays a critical role in suppressing the development of these cancers.
DIRAS3 is also known as ARHI, NOEY2.
