Affordable Access

Limited functional equivalence of phylogenetic variation in small nuclear RNA: yeast U2 RNA with altered branchpoint complementarity inhibits splicing and produces a dominant lethal phenotype.

Authors
  • Miraglia, L
  • Seiwert, S
  • Igel, A H
  • Ares, M Jr
Type
Published Article
Journal
Proceedings of the National Academy of Sciences of the United States of America
Publication Date
Aug 15, 1991
Volume
88
Issue
16
Pages
7061–7065
Identifiers
PMID: 1871121
Source
Medline
License
Unknown

Abstract

U2 is a highly conserved small nuclear RNA essential for pre-mRNA splicing in mammals and yeast and for trans-splicing in trypanosomes. To test the function of variant U2 RNA structures from different organisms, we conducted phylogenetic exchanges of U2 domains. Replacing nucleotides 1-120 of yeast U2 with the corresponding region of human U2 generates a U2 RNA that is correctly folded and functions in yeast. In contrast, replacement of the branchpoint interaction region of yeast U2 with the corresponding region from trypanosome is dominant lethal. Using a GAL-U2 promoter fusion, we show that the dominant phenotype can be made conditional and that the accumulation of mutant U2 is followed rapidly by inhibition of nuclear pre-mRNA splicing. The results suggest that U2 small nuclear ribonucleoprotein particles normally participate in stable complexes with a limiting splicing factor prior to formation of U2-intron branchpoint base pairs.

Report this publication

Statistics

Seen <100 times