Biological Activity
SMEK1 (SMEK homolog 1) is a regulatory subunit of serine/threonine-protein phosphatase 4. It regulates the activity of PP4C (protein phosphatase 4 catalytic subunit) at centrosomal microtubule organizing centers. It forms a complex with PP4C, PP4R2, and PP4R3β th at dephosphorylates ATR (ataxia telangiectasia and Rad3 related)-mediated γ-H2AX (histone H2A variant) which is generated during DNA replication. In association with BLU (Bendless-like ubiquitin-conjugating enzyme), a tumor suppressor gene, SMEK1 acts in the transcriptional regulation. It also plays an important role in histone deacetylation and Wnt silencing, essential for embryonic stem cells (ESCs) pluripotency maintenance.
