Arabidopsis PPP family of serine/threonine phosphatases

Trends Plant Sci. 2007 Apr;12(4):169-76. doi: 10.1016/j.tplants.2007.03.003. Epub 2007 Mar 23.


Serine/threonine-specific phosphoprotein phosphatases (PPPs) are ubiquitous enzymes in all eukaryotes, but their regulatory functions are largely unknown in higher plants. The Arabidopsis genome encodes 26 PPP catalytic subunits related to type 1, type 2A and so-called novel phosphatases, including four plant-specific enzymes carrying large N-terminal kelch-domains, but no apparent homologue of the PP2B family. The catalytic subunits of PPPs associate with regulatory protein partners that target them to well defined cellular locations and modulate their activity. Recent studies of phosphatase partners and their interactions have directed attention again to functional dissection of plant PPP families, and highlight their intriguing roles in the regulation of metabolism, cell cycle and development, as well as their roles in light, stress and hormonal signalling.

Publication types

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

MeSH terms

  • Arabidopsis / enzymology*
  • Arabidopsis Proteins / chemistry
  • Arabidopsis Proteins / classification
  • Arabidopsis Proteins / physiology*
  • Models, Biological*
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / physiology
  • Phosphoprotein Phosphatases / chemistry
  • Phosphoprotein Phosphatases / classification
  • Phosphoprotein Phosphatases / physiology*
  • Phylogeny
  • Protein Structure, Tertiary
  • Protein Subunits / metabolism
  • Protein Subunits / physiology


  • Arabidopsis Proteins
  • Nuclear Proteins
  • Protein Subunits
  • PP7 protein, Arabidopsis
  • Phosphoprotein Phosphatases
  • protein phosphatase 5
  • protein phosphatase 6