ISSN:
1617-4623
Keywords:
Key words G2 pea
;
GDA-1
;
Gibberellin
;
Photoperiod
;
Senescence
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Using cDNA representational difference analysis (cDNA RDA), we isolated a cDNA named GDA-1 from a cDNA library constructed with mRNA from short-day (SD) grown G2 pea apical tissue. The amino acid sequence deduced from GDA-1 shares partial identity with the B2 protein which is expressed during embryogenesis of carrot cells. Northern analysis showed that GDA-1 mRNA is abundant in SD-grown G2 pea apical buds. In long-day (LD) conditions, there was almost no detectable GDA-1 mRNA. When LD-grown G2 peas were kept in continuous darkness for 24 h, the GDA-1 mRNA content reached a level equivalent to about 50% of that in the SD samples. On the other hand, when SD-grown peas were transferred into the light for 24 h, the amount of hybridizable GDA-1 mRNA dropped to the same as that of LD-grown plants. GDA-1 expression was found to be independent of flower initiation time. GA3 application in vitro resulted in rapid accumulation of GDA-1 mRNA in LD-grown G2 pea apical buds, which is compatible with its delaying effect on apical senescence. Time-course experiments revealed that GDA-1 is induced within 15 min of GA3 application. Exogenous GA3 did not influence the expression of GDA-1 in SD-grown G2 peas. Since both photoperiod and GA induce the expression of GDA-1, we speculate that they may activate similar signal transduction pathways in G2 peas. Our work also shows that photoperiod may change the efficiency of gibberellin perception by plants.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004380050828
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