Small nucleolar RNA SNORD27 (SNORD27)

Small nucleolar RNA SNORD27 is a noncoding RNA of the box C/D class found in the nucleolus, characterized by conserved C (UGAUGA) and D (CUGA) box motifs[4]. Its canonical function is to guide the site-specific 2′-O-methylation of adenosine 27 in 18S rRNA by directing the methyltransferase fibrillarin[1][2]. Beyond its role in rRNA biogenesis, SNORD27 is also found in a fibrillarin-free nuclear fraction, where it associates with spliceosomal complexes and regulates the alternative splicing of specific pre-mRNAs (notably E2F7, a cell cycle regulator, as well as MAP4K3, ZBTB37, FER, and ABCA8)[1][2][5]. This splicing regulation is achieved by base pairing to pre-mRNA sequences near splice sites, sometimes suppressing the inclusion of cryptic or weak alternative exons[1][2]. Thus, SNORD27 links ribosome biogenesis and RNA splicing, and its dysregulation has implications in cancer and cell proliferation[2][3].

Other names

SNORD27U27Small nucleolar RNA SNORD27LOC124900339