Similar mechanisms might be triggered by alternative external stimuli that induce dormancy release in grape buds.
The detection of genes having similar expression profiles following the application of different stimuli that trigger bud break may constitute potent tools for the identification of pathways with a central role in dormancy release. We compared the effects of heat shock (HS) and hydrogen cyanamide (HC) and demonstrated that HS leads to earlier and higher bud-break levels. Changes in transcript levels of catalase, alcohol dehydrogenase and pyruvate decarboxylase were induced following both treatments. However, timing and extent of changes in transcript level differed. Changes occurred earlier in HS-treated buds and were more intense in HC-treated buds. The changes in transcript levels after both treatments were temporary. The rapid and short-lasting changes in gene expression following HS treatment correlated with the faster and higher level of bud-break that this treatment exerted. This correlation may propose that the reported molecular events are mechanistically involved in dormancy release. To test the hypothesis that temporary oxidative stress is part of the mechanism inducing dormancy release, we analyzed the effect of HS and HC treatments on the expression of ascorbate peroxidase, glutathione reductase, thioredoxin h, glutathione S-transferase and sucrose synthase genes and found that they were induced by both treatments in a similar pattern. Taken together, these findings propose that similar cellular processes might be triggered by different stimuli that lead to dormancy release, and are consistent with the hypothesis that temporary oxidative stress and respiratory stress might be part of the mechanism that leads to bud break.
Halaly
Tamar
T
Department of Fruit Tree Sciences, Institute of Horticulture, Agricultural Research Organization, The Volcani Center, Bet Dagan, P.O. Box 6, 50250, Bet Dagan, Israel.
Pang
Xuequn
X
Batikoff
Tamar
T
Crane
Omer
O
Keren
Alexandra
A
Venkateswari
Jaganatha
J
Ogrodovitch
Aliza
A
Sadka
Avi
A
Lavee
Shimon
S
Or
Etti
E
D000426:Alcohol Dehydrogenase / Q000235:genetics; D060387:Ascorbate Peroxidases; D015152:Blotting, Northern; D002374:Catalase / Q000235:genetics; D003484:Cyanamide / Q000494:pharmacology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005964:Glucosyltransferases / Q000235:genetics; D005980:Glutathione Reductase / Q000235:genetics; D005982:Glutathione Transferase / Q000235:genetics; D006358:Hot Temperature; D018519:Meristem / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D018384:Oxidative Stress; D010544:Peroxidases / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics*; D011767:Pyruvate Decarboxylase / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013696:Temperature; D054480:Thioredoxin h / Q000235:genetics; D027843:Vitis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development
D010940:Plant Proteins; D054480:Thioredoxin h; D003484:Cyanamide; D000426:Alcohol Dehydrogenase; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D002374:Catalase; D005980:Glutathione Reductase; D005964:Glucosyltransferases; C022699:sucrose synthase; D005982:Glutathione Transferase; D011767:Pyruvate Decarboxylase