A yeast heterogeneous nuclear ribonucleoprotein complex associated with RNA polymerase II

Genetics. 2000 Feb;154(2):557-71.

Abstract

Recent evidence suggests a role for the carboxyl-terminal domain (CTD) of the largest subunit of RNA polymerase II (pol II) in pre-mRNA processing. The yeast NRD1 gene encodes an essential RNA-binding protein that shares homology with mammalian CTD-binding proteins and is thought to regulate mRNA abundance by binding to a specific cis-acting element. The present work demonstrates genetic and physical interactions among Nrd1p, the pol II CTD, Nab3p, and the CTD kinase CTDK-I. Previous studies have shown that Nrd1p associates with the CTD of pol II in yeast two-hybrid assays via its CTD-interaction domain (CID). We show that nrd1 temperature-sensitive alleles are synthetically lethal with truncation of the CTD to 9 or 10 repeats. Nab3p, a yeast hnRNP, is a high-copy suppressor of some nrd1 temperature-sensitive alleles, interacts with Nrd1p in a yeast two-hybrid assay, and coimmunoprecipitates with Nrd1p. Temperature-sensitive alleles of NAB3 are suppressed by deletion of CTK1, a kinase that has been shown to phosphorylate the CTD and increase elongation efficiency in vitro. This set of genetic and physical interactions suggests a role for yeast RNA-binding proteins in transcriptional regulation.

Publication types

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

MeSH terms

  • Alleles
  • Base Sequence
  • DNA Primers
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Genes, Suppressor
  • Heterogeneous-Nuclear Ribonucleoproteins
  • Phosphorylation
  • Precipitin Tests
  • Protein Binding
  • RNA Polymerase II / metabolism*
  • RNA Precursors / metabolism
  • RNA Processing, Post-Transcriptional
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins
  • Ribonucleoproteins / genetics
  • Ribonucleoproteins / metabolism*
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Temperature
  • Transcription, Genetic

Substances

  • DNA Primers
  • Fungal Proteins
  • Heterogeneous-Nuclear Ribonucleoproteins
  • NRD1 protein, S cerevisiae
  • RNA Precursors
  • RNA, Messenger
  • RNA-Binding Proteins
  • Ribonucleoproteins
  • Saccharomyces cerevisiae Proteins
  • RNA Polymerase II