Strboh A homologue of NADPH oxidase regulates wound-induced oxidative burst and facilitates wound-healing in potato tubers

Planta. 2007 Dec;227(1):25-36. doi: 10.1007/s00425-007-0589-9. Epub 2007 Jul 26.


During 30-months of storage at 4 degrees C, potato (Solanum tuberosum L.) tubers progressively lose the ability to produce superoxide in response to wounding, resist microbial infection, and develop a suberized wound periderm. Using differentially aged tubers, we demonstrate that Strboh A is responsible for the wound-induced oxidative burst in potato and aging attenuates its expression. In vivo superoxide production and NADPH oxidase (NOX) activity from 1-month-old tubers increased to a maximum 18-24 h after wounding and then decreased to barely detectable levels by 72 h. Wounding also induced a 68% increase in microsomal protein within 18 h. These wound-induced responses were lost over a 25- to 30-month storage period. Superoxide production and NOX activity were inhibited by diphenylene iodonium chloride, a specific inhibitor of NOX, which in turn effectively inhibited wound-healing and increased susceptibility to microbial infection and decay in 1-month-old tubers. Wound-induced superoxide production was also inhibited by EGTA-mediated destabilization of membranes. The ability to restore superoxide production to EGTA-treated tissue with Ca(+2) declined with advancing tuber age, likely a consequence of age-related changes in membrane architecture. Of the five homologues of NOX (Strboh A-D and F), wounding induced the expression of Strboh A in 6-month-old tubers but this response was absent in tubers stored for 25-30 months. Strboh A thus mediates the initial burst of superoxide in response to wounding of potato tubers; loss of its expression increases the susceptibility to microbial infection and contributes to the age-induced loss of wound-healing ability.

Publication types

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

MeSH terms

  • Calcium / metabolism
  • Calcium / physiology
  • Chlorpromazine / pharmacology
  • Edetic Acid / pharmacology
  • Models, Biological
  • NADPH Oxidases / genetics
  • NADPH Oxidases / metabolism*
  • Onium Compounds / pharmacology
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plant Tubers / genetics
  • Plant Tubers / metabolism*
  • Respiratory Burst
  • Reverse Transcriptase Polymerase Chain Reaction
  • Solanum tuberosum / enzymology*
  • Solanum tuberosum / genetics
  • Stress, Mechanical
  • Superoxides / metabolism
  • Time Factors


  • Onium Compounds
  • Plant Proteins
  • Superoxides
  • diphenyleneiodonium
  • Edetic Acid
  • NADPH Oxidases
  • Calcium
  • Chlorpromazine