Metabolic Acclimation to Anoxia Induced by Low (2-4 kPa Partial Pressure) Oxygen Pretreatment (Hypoxia) in Root Tips of Zea mays.

  title={Metabolic Acclimation to Anoxia Induced by Low (2-4 kPa Partial Pressure) Oxygen Pretreatment (Hypoxia) in Root Tips of Zea mays.},
  author={Pierre H. Saglio and Malcolm C. Drew and Alain Pradet},
  journal={Plant physiology},
  volume={86 1},
Young intact plants of maize (Zea mays L. cv INRA 508) were exposed to 2 to 4 kilopascals partial pressure oxygen (hypoxic pretreatment) for 18 hours before excision of the 5 millimeter root apex and treatment with strictly anaerobic conditions (anoxia). Hypoxic acclimation gave rise to larger amounts of ATP, to larger ATP/ADP and adenylate energy charge ratios, and to higher rates of ethanol production when excised root tips were subsequently made anaerobic, compared with root tips transferred… Expand
Enhancement of Anaerobic Respiration in Root Tips of Zea mays following Low-Oxygen (Hypoxic) Acclimation.
A period of low oxygen partial pressure is necessary to permit adequate acclimation of the root tip of maize to subsequent anoxia, resulting in more rapid rates of fermentation and generation of ATP. Expand
Hypoxic and Anoxic Induction of Alcohol Dehydrogenase in Roots and Shoots of Seedlings of Zea mays (Adh Transcripts and Enzyme Activity)
In root tips, ADH induction by anoxia was small and transient relative to induction by hypoxia, and higher levels of Adh1 transcripts and enzyme activity were maintained for at least 48 h in root axes and shoots. Expand
Lactic Acid efflux as a mechanism of hypoxic acclimation of maize root tips to anoxia.
The presence of cycloheximide during pretreatment abolished this difference, suggesting that the greater efficiency of lactate efflux was linked to protein synthesis, and could account for the higher cytoplasmic pH values always found in pretreated tissues. Expand
Hypoxic Induction of Anoxia Tolerance in Roots of Adh1 Null Zea mays L
Although enhancedADH activity may have raised fermentation rates in acclimated Adh1- tissues and thereby contributed to energy metabolism and viability, the high levels of ADH activity inducible in acclamated, wild-type maize root tips appear to be in excess of that required to increase rates of fermentation. Expand
Hypoxic Induction of Anoxia Tolerance in Root Tips of Zea mays.
Improved viability of hypoxically pretreated root tips was associated with maintenance of a high energy metabolism (ATP concentration, total adenylates, and adenYLate energy charge), and Roots that were not pretreated lost 94% of the total adanylates and ATP at 24 hours of anoxia. Expand
The Role of Sugars, Hexokinase, and Sucrose Synthase in the Determination of Hypoxically Induced Tolerance to Anoxia in Tomato Roots
Sucrose, but not glucose or fructose, was able to sustain glycolytic flux via the sucrose synthase pathway and allowed anoxic tolerance of acclimated roots and the ability of tomato roots to survive anoxia. Expand
The Response of Maize Seedlings of Different Ages to Hypoxic and Anoxic Stress (Changes in Induction of Adh1 mRNA, ADH Activity, and Survival of Anoxia)
In general, younger seedlings had higher initial (aerobic) levels of total protein, Adh1 transcripts, and ADH activity than did seedlings that were 2 d older, and roots of seedlings of either age showed a similar resistance to anoxia. Expand
Effect of hypoxic acclimation on anoxia tolerance in Vitis roots: response of metabolic activity and K+ fluxes.
Improved tolerance was mainly driven by an enhanced activity of key enzymes in alcohol fermentation (ADC and PDC); the capability to maintain a higher level of respiration, evidenced by a lesser decrease in heat development and ATP production and the maintenance of a better ion homeostasis. Expand
Time requirement for hypoxic acclimation to anoxia tolerance in rice coleoptiles
The results suggest that the H-PT may increase anoxia tolerance due to maintenance of anaerobic glycolysis with induction of ethanolic fermentation to generate ATP, and hypoxic acclimation toanoxic stress in rice coleoptiles may occur within 6 h. Expand
Metabolic Acclimation to Anoxic Conditions and Biochemical Basis of Death
Exposure to hypoxic conditions induces a metabolic acclimation which improves the survival of maize root systems under subsequent extreme anoxic conditions. The regulation of cytoplasmic pH isExpand