Identification and purification of a 62,000-dalton protein that binds specifically to the polypyrimidine tract of introns.


Journal Article

A protein of molecular size 62,000 daltons (p62) was detected in HeLa cell nuclear extracts by UV cross-linking to mRNA precursors. p62 binds specifically to the polypyrimidine tract of the 3' splice site region of introns. p62 purified to homogeneity binds the polypyrimidine tract of pre-mRNAs. This binding does not require the AG dinucleotide at the 3' splice site. Alterations in the polypyrimidine tract that reduce the binding of p62 yield a corresponding reduction in the efficiency of formation of a U2 snRNP/pre-mRNA complex and splicing. The p62 protein is retained in the spliceosome, where it remains bound to the pre-mRNA. This polypyrimidine tract binding protein (pPTB) is proposed to be a critical component in recognition of the 3' splice site during splicing.

Full Text

Duke Authors

Cited Authors

  • García-Blanco, MA; Jamison, SF; Sharp, PA

Published Date

  • December 1989

Published In

Volume / Issue

  • 3 / 12A

Start / End Page

  • 1874 - 1886

PubMed ID

  • 2533575

Pubmed Central ID

  • 2533575

International Standard Serial Number (ISSN)

  • 0890-9369

Digital Object Identifier (DOI)

  • 10.1101/gad.3.12a.1874


  • eng

Conference Location

  • United States