Z25, a novel intronic snoRNA encoded in mammalian nucleolin gene

A novel intronic small nucleolar RNA (snoRNA), termed Z25, was identified f rom mammals by computer analysis and experimental sequence methods. Z25 is a 69 nucleotides long RNA containing typical boxC/D motifs, terminal stem a nd an Il-nucleotide sequence complementary to 18S rRNA. in theory, Z25 func tions as or RNA guide for the 2'-O-ribose methylation of adenine at positio n 1678 (human 18S rRNA coordinate) in 18S rRNA. Z25 snoRNA gene was found t o be located in the fifth intron of nucleolin gene of human, mouse and mt, demonstrating that the mammalian nucleoline gene is a host gene encoding mu ltiple snoRNAs.