HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Gibberellic acid and dwarfism effects on the growth dynamics of B73 maize (Zea mays L.) leaf blades: a transient increase in apoplastic peroxidase activity precedes cessation of cell elongation.

Abstract
The relationship between apoplastic peroxidase (EC 1.11.1.7) activity and cessation of growth in maize (Zea mays L.) leaf blades was investigated by altering elongation zone length. Apoplastic peroxidase activity in the elongation and secondary cell wall deposition zones of elongating leaf blades of the maize inbred line B73 was used as a control and compared to leaves of the dwarf mutant D8-81127, a near-isogenic line of B73 unresponsive to gibberellins, and to leaves of B73 plants to which gibberellic acid (GA(3)) had been applied via root uptake. Elongation zone length was increased by treatment with GA(3) through an increase in cell number as well as increased final cell length. The shorter elongation zone of dwarf leaves occurred primarily through reduced final cell length. Although elongation zone length differed among dwarf, control, and GA(3)-treated leaf blades, in all three treatments a transient increase in apoplastic peroxidase activity preceded a reduction in the segmental elongation rate in leaves. A peroxidase isoenzyme with pI 7.0 occurred in the leaf elongation zone during growth deceleration in all three treatments, and its activity decreased as growth displaced tissue into the region of secondary cell wall deposition. Growth cessation for all treatments coincided with the first appearance of peroxidase isozymes with pIs of 5.6 and 5.7. Based on the activity of particular isozymes relative to growth and differentiation, the pI 7.0 isoenzyme is most likely to be involved in cessation of cell elongation, while isozymes with pIs 5.6 and 5.7 are likely to be active in lignification.
AuthorsI R de Souza, J W MacAdam
JournalJournal of experimental botany (J Exp Bot) Vol. 52 Issue 361 Pg. 1673-82 (Aug 2001) ISSN: 0022-0957 [Print] England
PMID11479332 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Gibberellins
  • Isoenzymes
  • Plant Growth Regulators
  • Lignin
  • gibberellic acid
  • Peroxidase
Topics
  • Biological Transport
  • Cell Differentiation (physiology)
  • Cell Division (drug effects, physiology)
  • Cell Wall (drug effects, enzymology)
  • Gibberellins (metabolism, pharmacology)
  • Isoelectric Point
  • Isoenzymes (metabolism)
  • Lignin (biosynthesis)
  • Meristem (drug effects, growth & development, metabolism)
  • Models, Biological
  • Peroxidase (metabolism)
  • Plant Epidermis (drug effects, growth & development, metabolism)
  • Plant Growth Regulators (metabolism, pharmacology)
  • Plant Leaves (drug effects, enzymology, growth & development, metabolism)
  • Zea mays (enzymology, growth & development, metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: