RNA recognition motif 1 (RRM1) and 2 (RRM2) found in vertebrate nuclear protein 220 (NP220)
This subgroup corresponds to RRM1 and RRM2 of NP220, also termed zinc finger protein 638 (ZN638), or cutaneous T-cell lymphoma-associated antigen se33-1, or zinc finger matrin-like protein, a large nucleoplasmic DNA-binding protein that binds to cytidine-rich sequences, such as CCCCC (G/C), in double-stranded DNA (dsDNA). NP220 contains multiple domains, including MH1, MH2, and MH3, domains homologous to the acidic nuclear protein matrin 3; RS, an arginine/serine-rich domain commonly found in pre-mRNA splicing factors; PstI-HindIII, a domain essential for DNA binding; acidic repeat, a domain with nine repeats of the sequence LVTVDEVIEEEDL; and a Cys2-His2 zinc finger-like motif that is also present in matrin 3. It may be involved in packaging, transferring, or processing transcripts. This subgroup corresponds to the domain of MH2 that contains two tandem RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).
Jiyao W et al.(2023). "The conserved domain database in 2023.",