Summary
Performance
Immunogen
Application
Background
Fibrillarin is a 2'-O-methyltransferase located in fibrillar regions and Cajal bodies of the nucleolus, where RNA transcription and pre-RNA processing take place. Fibrillarin associates with several other structual proteins as well as box C/D snoRNA to form a complex that functions in pre-rRNA processing, pre-rRNA methylation and ribosome assembly. This complex catalyzes site-specific 2'-O-ribose methylation of targeted nucleotides within the rRNA sequence. The sequence, structure and function of fibrillarin are highly conserved and fibrillarin gene expression is essential for early embryonic development. S-adenosyl-L-methionine-dependent methyltransferase that has the ability to methylate both RNAs and proteins (PubMed:24352239, PubMed:30540930, PubMed:32017898). Involved in pre-rRNA processing by catalyzing the site-specific 2'-hydroxyl methylation of ribose moieties in pre-ribosomal RNA (PubMed:30540930). Site specificity is provided by a guide RNA that base pairs with the substrate (By similarity). Methylation occurs at a characteristic distance from the sequence involved in base pairing with the guide RNA (By similarity). Probably catalyzes 2'-O-methylation of U6 snRNAs in box C/D RNP complexes (PubMed:32017898). U6 snRNA 2'-O-methylation is required for mRNA splicing fidelity (PubMed:32017898). Also acts as a protein methyltransferase by mediating methylation of 'Gln-105' of histone H2A (H2AQ104me), a modification that impairs binding of the FACT complex and is specifically present at 35S ribosomal DNA locus (PubMed:24352239, PubMed:30540930).
Research Area
