Two conserved domains in regulatory B subunits mediate binding to the A subunit of protein phosphatase 2A.


Journal Article

Protein phosphatase 2A (PP2A) is an abundant heterotrimeric serine/threonine phosphatase containing highly conserved structural (A) and catalytic (C) subunits. Its diverse functions in the cell are determined by its association with a highly variable regulatory and targeting B subunit. At least three distinct gene families encoding B subunits are known: B/B55/CDC55, B'/B56/RTS1 and B"/PR72/130. No homology has been identified among the B families, and little is known about how these B subunits interact with the PP2A A and C subunits. In vitro expression of a series of B56alpha fragments identified two distinct domains that bound independently to the A subunit. Sequence alignment of these A subunit binding domains (ASBD) identified conserved residues in B/B55 and PR72 family members. The alignment successfully predicted domains in B55 and PR72 subunits that similarly bound to the PP2A A subunit. These results suggest that these B subunits share a common core structure and mode of interaction with the PP2A holoenzyme.

Full Text

Duke Authors

Cited Authors

  • Li, X; Virshup, DM

Published Date

  • January 2002

Published In

Volume / Issue

  • 269 / 2

Start / End Page

  • 546 - 552

PubMed ID

  • 11856313

Pubmed Central ID

  • 11856313

International Standard Serial Number (ISSN)

  • 0014-2956

Digital Object Identifier (DOI)

  • 10.1046/j.0014-2956.2001.02680.x


  • eng

Conference Location

  • England