InterPro domain: IPR000692

Fibrillarin is a component of a nucleolar small nuclear ribonucleoprotein (SnRNP), functioning in vivo in ribosomal RNA processing [ 1 , 2 ]. It is associated with U3, U8 and U13 small nuclearRNAs in mammals [ 3 ] and is similar to the yeast NOP1 protein [ 3 ]. Fibrillarin has awell conserved sequence of around 320 amino acids, and contains 3 domains, an N-terminal Gly/Arg-richregion; a central domain resembling other RNA-binding proteins and containing an RNP-2-like consensussequence; and a C-terminal alpha-helical domain. An evolutionarily related pre-rRNA processing protein,which lacks the Gly/Arg-rich domain, has been found in various archaebacteria.

1. Evolutionary conservation of the human nucleolar protein fibrillarin and its functional expression in yeast. J. Cell Biol. 113, 715-29
2. Study of multiple fibrillarin mRNAs reveals that 3' end formation in Schizosaccharomyces pombe is sensitive to cold shock. Nucleic Acids Res. 21, 1881-7
3. A yeast nucleolar protein related to mammalian fibrillarin is associated with small nucleolar RNA and is essential for viability. EMBO J. 8, 4015-24