Sec14-nodulin proteins and the patterning of phosphoinositide landmarks for developmental control of membrane morphogenesis

Mol Biol Cell. 2015 May 1;26(9):1764-81. doi: 10.1091/mbc.E14-10-1475. Epub 2015 Mar 4.


Polarized membrane morphogenesis is a fundamental activity of eukaryotic cells. This process is essential for the biology of cells and tissues, and its execution demands exquisite temporal coordination of functionally diverse membrane signaling reactions with high spatial resolution. Moreover, mechanisms must exist to establish and preserve such organization in the face of randomizing forces that would diffuse it. Here we identify the conserved AtSfh1 Sec14-nodulin protein as a novel effector of phosphoinositide signaling in the extreme polarized membrane growth program exhibited by growing Arabidopsis root hairs. The data are consistent with Sec14-nodulin proteins controlling the lateral organization of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) landmarks for polarized membrane morphogenesis in plants. This patterning activity requires both the PtdIns(4,5)P2 binding and homo-oligomerization activities of the AtSfh1 nodulin domain and is an essential aspect of the polarity signaling program in root hairs. Finally, the data suggest a general principle for how the phosphoinositide signaling landscape is physically bit mapped so that eukaryotic cells are able to convert a membrane surface into a high-definition lipid-signaling screen.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / cytology
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / chemistry
  • Arabidopsis Proteins / physiology*
  • Binding Sites
  • Cell Membrane / physiology*
  • Cell Polarity
  • Molecular Dynamics Simulation
  • Morphogenesis
  • Phosphatidylinositol 4,5-Diphosphate / metabolism*
  • Phospholipid Transfer Proteins / chemistry
  • Phospholipid Transfer Proteins / physiology*
  • Plant Roots / growth & development
  • Plant Roots / metabolism*
  • Protein Binding
  • Signal Transduction


  • Arabidopsis Proteins
  • Phosphatidylinositol 4,5-Diphosphate
  • Phospholipid Transfer Proteins
  • Sfh1 protein, Arabidopsis