Expansins in growing tomato leaves

Plant J. 1995 Dec;8(6):795-802. doi: 10.1046/j.1365-313x.1995.8060795.x.


An expansin-like protein from growing tomato leaves was identified by its ability to restore the 'acid-growth' response to heat-inactivated tomato walls and by its similarity to expansins from cucumber hypocotyls. Native walls from growing tomato leaves exhibit an endogenous acid-induced extension (creep) that resembles in various biochemical characteristics the acid-growth activity of cucumber hypocotyls. For example, the acid-growth activity is lost when the walls of tomato leaves are briefly heated and is largely restored by addition of a crude protein extract from the walls of growing leaves. Wall proteins from growing leaves enhance the stress relaxation spectrum of tomato walls in a fashion characteristic of cucumber expansins. HPLC fractionation of the crude wall protein from tomato leaves yielded an active fraction containing a major 27 kDa protein that cross-reacts with an antibody raised against cucumber expansin. The results show that tomato leafwalls possess at least one expansin that is responsible for the acid-growth property of leaves and indicate that cell wall extension in leaves shares an underlying protein mechanism common to cell wall expansion in stems.

Publication types

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

MeSH terms

  • Cell Division
  • Cell Wall / chemistry
  • Cell Wall / physiology
  • Cucumis sativus / chemistry
  • Cucumis sativus / cytology*
  • Cucumis sativus / growth & development
  • Cucumis sativus / physiology
  • Hypocotyl / chemistry
  • Hypocotyl / cytology
  • Hypocotyl / growth & development
  • Hypocotyl / physiology
  • Lycopersicon esculentum / chemistry
  • Lycopersicon esculentum / cytology*
  • Lycopersicon esculentum / growth & development
  • Lycopersicon esculentum / physiology
  • Plant Leaves / chemistry
  • Plant Leaves / cytology*
  • Plant Leaves / growth & development
  • Plant Leaves / physiology
  • Plant Proteins / analysis*
  • Plant Proteins / chemistry
  • Plant Proteins / isolation & purification
  • Plant Proteins / physiology


  • Plant Proteins
  • expansin protein, plant