Functional characterization of the pleckstrin homology domain of a cellulose synthase from the oomycete Saprolegnia monoica

Biochem Biophys Res Commun. 2012 Jan 27;417(4):1248-53. doi: 10.1016/j.bbrc.2011.12.118. Epub 2012 Jan 3.


Some oomycetes, for instance Saprolegnia parasitica, are severe fish pathogens that cause important economic losses worldwide. Cellulose biosynthesis is a vital process for this class of microorganisms, but the corresponding molecular mechanisms are poorly understood. Of all cellulose synthesizing enzymes known, only some oomycete cellulose synthases contain a pleckstrin homology (PH) domain. Some human PH domains bind specifically to phosphoinositides, but most PH domains bind phospholipids in a non-specific manner. In addition, some PH domains interact with various proteins. Here we have investigated the function of the PH domain of cellulose synthase 2 from the oomycete Saprolegnia monoica (SmCesA2), a species closely related to S. parasitica. The SmCesA2 PH domain is similar to the C-terminal PH domain of the human protein TAPP1. It binds in vitro to phosphoinositides, F-actin and microtubules, and co-localizes with F-actin in vivo. Our results suggest a role of the SmCesA2 PH domain in the regulation, trafficking and/or targeting of the cell wall synthesizing enzyme.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Amino Acid Sequence
  • Blood Proteins / chemistry*
  • Blood Proteins / metabolism
  • Cell Line, Tumor
  • Computational Biology
  • Glucosyltransferases / chemistry*
  • Glucosyltransferases / metabolism
  • Humans
  • Intracellular Signaling Peptides and Proteins / chemistry*
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Membrane Proteins / chemistry*
  • Membrane Proteins / metabolism
  • Microtubules / metabolism
  • Molecular Sequence Data
  • Phosphatidylinositols / chemistry
  • Phosphatidylinositols / metabolism
  • Phosphoproteins / chemistry*
  • Phosphoproteins / metabolism
  • Protein Structure, Tertiary
  • Saprolegnia / enzymology*
  • Sequence Alignment


  • Actins
  • Blood Proteins
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • PLEKHA1 protein, human
  • Phosphatidylinositols
  • Phosphoproteins
  • platelet protein P47
  • Glucosyltransferases
  • cellulose synthase