Promoter-selective activation domains in Oct-1 and Oct-2 direct differential activation of an snRNA and mRNA promoter

Cell. 1992 Feb 21;68(4):755-67. doi: 10.1016/0092-8674(92)90150-b.


The promoter specificity of transcriptional activators is generally thought to be conferred by the specificity of the DNA-binding domain, which brings the activation domain to the appropriate promoter sequence. We show here, however, that Oct-1 and Oct-2 can differentially activate transcription not through DNA binding specificity but instead through the use of promoter-selective activation domains. These distinct activation domains lead to stimulation of the U2 small nuclear RNA promoter by Oct-1 and an mRNA promoter by Oct-2. An Oct-2 variant, called Oct-2B, differs from Oct-2 by an Oct-1-related C-terminal extension that results from alternative splicing. This variant gains the ability to activate the U2 small nuclear RNA promoter. Thus, the promoter selectivity of a transcriptional activator can be changed, in this case by alternative splicing, without affecting its DNA binding specificity.

Publication types

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

MeSH terms

  • DNA-Binding Proteins / genetics
  • Gene Expression Regulation
  • HeLa Cells
  • Humans
  • Models, Genetic
  • Promoter Regions, Genetic*
  • RNA Splicing
  • RNA, Messenger / genetics*
  • RNA, Small Nuclear / genetics*
  • Trans-Activators / genetics*
  • Transfection


  • DNA-Binding Proteins
  • RNA, Messenger
  • RNA, Small Nuclear
  • Trans-Activators