Functional crosstalk between exon enhancers, polypyrimidine tracts and branchpoint sequences. Journal Article uri icon

Overview

abstract

  • We recently identified enhancer elements that activate the weak 3' splice site of alpha-tropomyosin exon 2 as well as a variety of heterologous weak 3' splice sites. To understand their mechanism of action, we devised an iterative selection strategy to identify functional pyrimidine tracts and branchpoint sequences in the presence or absence of enhancer elements. Surprisingly, we found that strong pyrimidine tracts were selected regardless of the presence of enhancer elements. However, the presence of enhancer elements resulted in the selection of multiple, non-consensus branchpoint sequences. Thus, enhancer elements apparently activate weak 3' splice sites primarily by increasing the efficiency of splicing of introns containing branchpoint sequences with less than optimal U2-branchpoint pairing arrangements. Comparison of consensus sequences from both our selection strategy and compilations of published intron sequences suggests that exon enhancer elements could be widespread and play an important role in the selection of 3' splice sites.

publication date

  • December 1, 1997

Full Author List

  • Buvoli M; Mayer SA; Patton JG

Other Profiles

Additional Document Info

start page

  • 7174

end page

  • 7183

volume

  • 16

issue

  • 23