The Arabidopsis DESPERADO/AtWBC11 transporter is required for cutin and wax secretion

Plant Physiol. 2007 Dec;145(4):1345-60. doi: 10.1104/pp.107.105676. Epub 2007 Oct 19.

Abstract

The cuticle fulfills multiple roles in the plant life cycle, including protection from environmental stresses and the regulation of organ fusion. It is largely composed of cutin, which consists of C(16-18) fatty acids. While cutin composition and biosynthesis have been studied, the export of cutin monomers out of the epidermis has remained elusive. Here, we show that DESPERADO (AtWBC11) (abbreviated DSO), encoding a plasma membrane-localized ATP-binding cassette transporter, is required for cutin transport to the extracellular matrix. The dso mutant exhibits an array of surface defects suggesting an abnormally functioning cuticle. This was accompanied by dramatic alterations in the levels of cutin monomers. Moreover, electron microscopy revealed unusual lipidic cytoplasmatic inclusions in epidermal cells, disappearance of the cuticle in postgenital fusion areas, and altered morphology of trichomes and pavement cells. We also found that DSO is induced by salt, abscisic acid, and wounding stresses and its loss of function results in plants that are highly susceptible to salt and display reduced root branching. Thus, DSO is not only essential for developmental plasticity but also plays a vital role in stress responses.

Publication types

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

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily G
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Abscisic Acid / physiology
  • Adaptation, Physiological
  • Arabidopsis / metabolism*
  • Arabidopsis / physiology
  • Arabidopsis / ultrastructure
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Gene Expression
  • Genes, Reporter
  • Membrane Lipids / biosynthesis*
  • Mutation
  • Phenotype
  • Plant Epidermis / metabolism*
  • Plant Epidermis / ultrastructure
  • Plant Roots / metabolism
  • Salinity
  • Waxes / metabolism*

Substances

  • ABCG11 protein, Arabidopsis
  • ATP Binding Cassette Transporter, Subfamily G
  • ATP-Binding Cassette Transporters
  • Arabidopsis Proteins
  • CER5 protein, Arabidopsis
  • Membrane Lipids
  • Waxes
  • cutin
  • Abscisic Acid