Z7 SNORNA - A NEW SMALL NUCLEOLAR RNA FROM YEAST SACCHAROMYCES-CEREVISIAE

With computer analysis on the Genbank database and molecular hybridiza tion methods, a new small nucleolar RNA, termed Z7 snoRNA, was identif ied from S. cerevisiae. Z7 snoRNA, possessing boxC, boxD elements and a 14 nt segment complementary to a conserved sequence of 18S rRNA, bel ongs to the snoRNA family which is involved in rRNA methylation. Z7 sn oRNA guides a 2'-O-ribose methylation of uridine at position 578 in ye ast 18s rRNA. Z7 snoRNA is 88 nts in length, accumulated in nucleolus, and is encoded by an independent gene located on the chromosome XIII of yeast.