Modification of U6 spliceosomal RNA is guided by other small RNAs

Mol Cell. 1998 Nov;2(5):629-38. doi: 10.1016/s1097-2765(00)80161-6.

Abstract

The vertebrate spliceosomal snRNAs are highly modified by pseudouridylation and 2'-O-methylation. We have identified novel conserved small RNAs that can direct addition of two methyl groups in U6 snRNA, at A47 and C77. These guide RNAs, mgU6-47 (methylation guide for U6 snRNA residue 47) and mgU6-77 contain boxes C, C', D, and D' and associate with fibrillarin. Each RNA can form a duplex with U6 snRNA positioning A47 and C77 for 2'-O-methylation. The antisense element of mgU6-77 can also position C2970 of 28S rRNA for 2'-O-methylation. Depletion of mgU6-77 from Xenopus oocytes prevents 2'-O-methylation of both C77 in U6 and C2970 in 28S; methylation can be restored by injecting in vitro transcribed mgU6-77. Thus, mgU6-77 appears to function in the 2'-O-methylation of two distinct classes of cellular RNA, snRNA, and rRNA.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Cell Fractionation
  • Cell Line
  • Cell Nucleolus / metabolism
  • Chromosomal Proteins, Non-Histone / immunology
  • Chromosomal Proteins, Non-Histone / metabolism
  • Dimerization
  • HeLa Cells
  • Humans
  • Methylation / drug effects
  • Mice
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Oligodeoxyribonucleotides, Antisense / pharmacology
  • Oocytes
  • Precipitin Tests
  • RNA, Ribosomal, 28S / metabolism
  • RNA, Small Nuclear / chemistry
  • RNA, Small Nuclear / genetics
  • RNA, Small Nuclear / metabolism*
  • RNA, Small Nuclear / pharmacology
  • Ribonuclease H / metabolism
  • Spliceosomes / chemistry
  • Spliceosomes / metabolism*
  • Xenopus laevis

Substances

  • Chromosomal Proteins, Non-Histone
  • Oligodeoxyribonucleotides, Antisense
  • RNA, Ribosomal, 28S
  • RNA, Small Nuclear
  • fibrillarin
  • Ribonuclease H

Associated data

  • GENBANK/AF084536