Enzymes and other agents that enhance cell wall extensibility

Annu Rev Plant Physiol Plant Mol Biol. 1999;50:391-417. doi: 10.1146/annurev.arplant.50.1.391.


Polysaccharides and proteins are secreted to the inner surface of the growing cell wall, where they assemble into a network that is mechanically strong, yet remains extensible until the cells cease growth. This review focuses on the agents that directly or indirectly enhance the extensibility properties of growing walls. The properties of expansins, endoglucanases, and xyloglucan transglycosylases are reviewed and their postulated roles in modulating wall extensibility are evaluated. A summary model for wall extension is presented, in which expansin is a primary agent of wall extension, whereas endoglucanases, xyloglucan endotransglycosylase, and other enzymes that alter wall structure act secondarily to modulate expansin action.

Publication types

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

MeSH terms

  • Cell Wall / enzymology
  • Cellulase / metabolism*
  • Cellulose / metabolism
  • Glycosyltransferases / metabolism*
  • Models, Biological
  • Plant Cells*
  • Plant Development
  • Plant Physiological Phenomena
  • Plant Proteins / metabolism*
  • Plants / enzymology*
  • Plants / metabolism
  • Polysaccharides / metabolism


  • Plant Proteins
  • Polysaccharides
  • expansin protein, plant
  • Cellulose
  • Glycosyltransferases
  • xyloglucan endotransglycosylase
  • Cellulase