forkhead associated (FHA) domain found in microspherule protein 1 (MCRS1) and similar proteins
MCRS1, also called 58 kDa microspherule protein (MSP58), cell cycle-regulated factor p78, or INO80 complex subunit J, is a nuclear RNA-binding protein that interacts with fragile X mental retardation protein in polyribosomal ribonucleoparticles (mRNPs) from neurons. It is a cell-cycle-dependent protein that acts as an inhibitor of TERT telomerase activity. It associates with LPTS/PinX1 and reduces the telomere length. It modulates the transcription repressor activity of DAXX by recruiting it to the nucleolus. As part of the NSL complex, MCRS1 may be involved in acetylation of nucleosomal histone H4 on several lysine residues. MCRS1 is also a putative regulatory component of the chromatin remodeling INO80 complex, which is involved in transcriptional regulation, DNA replication, and probably DNA repair. MCRS1 contains an FHA domain at its C-terminus. The FHA domain is a small phosphopeptide recognition module.
Feature 1:putative phosphopeptide binding site [polypeptide binding site]
Evidence:
Comment: based on structures of other FHA domains with bound phosphopeptide
Comment:GR at the C terminus of strand beta3, SRxH just preceding beta5, and motif SxNG in the beta6-beta7 turn indicate a canonical mode of pThr recognition.
Comment:Conserved residues are involved in binding directly to the ligand backbone and phosphate group. Non-conserved residues may determine binding specificity.