This family consists of various Pre RNA processing ribonucleoproteins. The function of the aligned region is unknown however it may be a common RNA or snoRNA or Nop1p binding domain. Nop5p (Nop58p) Q12499 from yeast is the protein component of a ribonucleoprotein required for pre-18s rRNA processing and is suggested to function with Nop1p in a snoRNA complex . Nop56p O00567 and Nop5p interact with Nop1p and are required for ribosome biogenesis . Prp31p p49704 is required for pre-mRNA splicing in S. cerevisiae . Fibrillarin, or Nop, is the catalytic subunit responsible for the methyl transfer reaction of the site-specific 2'-O-methylation of ribosomal and spliceosomal RNA .
The Nop domain is present in various pre-RNA processing ribonucleoproteins (RNP):
Wu P, Brockenbrough JS, Metcalfe AC, Chen S, Aris JP; , J Biol Chem 1998;273:16453-16463.: Nop5p is a small nucleolar ribonucleoprotein component required for pre- 18 S rRNA processing in yeast. PUBMED:9632712 EPMC:9632712 .
Gautier T, Berges T, Tollervey D, Hurt E; , Mol Cell Biol 1997;17:7088-7098.: Nucleolar KKE/D repeat proteins Nop56p and Nop58p interact with Nop1p and are required for ribosome biogenesis. PUBMED:9372940 EPMC:9372940 .
Weidenhammer EM, Singh M, Ruiz-Noriega M, Woolford JL Jr; , Nucleic Acids Res. 1996;24:1164-1170.: The PRP31 gene encodes a novel protein required for pre-mRNA splicing in Saccharomyces cerevisiae. PUBMED:8604353 EPMC:8604353 .
Xue S, Wang R, Yang F, Terns RM, Terns MP, Zhang X, Maxwell ES, Li H;, Mol Cell. 2010;39:939-949.: Structural basis for substrate placement by an archaeal box C/D ribonucleoprotein particle. PUBMED:20864039 EPMC:20864039.