UBE2A

Description

The UBE2A (ubiquitin conjugating enzyme E2 A) is a protein-coding gene located on chromosome X.

UBE2A, encoded by the UBE2A gene, is a human protein involved in ubiquitination, a crucial cellular process for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves three classes of enzymes: E1s (ubiquitin-activating enzymes), E2s (ubiquitin-conjugating enzymes), and E3s (ubiquitin-protein ligases). UBE2A belongs to the E2 ubiquitin-conjugating enzyme family and is essential for post-replicative DNA damage repair. It interacts with RAD18, UBR4, and P53. Mutations in UBE2A are linked to X-linked intellectual disability type Nascimento (Nascimento syndrome), characterized by intellectual disability, facial abnormalities, seizures, speech impairment, motor delay, micropenis, and skin problems. Multiple transcript variants encoding distinct isoforms exist for this gene.

UBE2A accepts ubiquitin from the E1 complex and catalyzes its attachment to other proteins. In partnership with the E3 enzyme BRE1 (RNF20 and/or RNF40), it plays a role in transcription regulation by catalyzing the monoubiquitination of histone H2B at 'Lys-120' to form H2BK120ub1. This modification acts as a specific tag for epigenetic transcriptional activation, elongation by RNA polymerase II, telomeric silencing, and is essential for H3K4me and H3K79me formation. In vitro, UBE2A catalyzes both 'Lys-11' and 'Lys-48' linked polyubiquitination. It is crucial for postreplication repair of UV-damaged DNA.

UBE2A is also known as HHR6A, MRXS30, MRXSN, RAD6A, UBC2.

Associated Diseases

• X-linked intellectual disability, Nascimento type
• Mental retardation, X-linked, syndromic, Nascimento type