Cloning and Expression of Dehydrin Genes in Blueberry

Previous studies identified three major chilling-responsive proteins of 65, 60, and 14 kDa whose levels increase in floral buds of blueberry during cold acclimation and decrease during deacclimation and resumption of growth. Characterization of these proteins found them to be members of a family of proteins responsive to drought and low temperature stress called dehydrins. The 65- and 60-kDa proteins were purified, digested into peptides, and several peptides from each were sequenced. The sequence information was used to synthesize degenerate DNA primers for amplification of a part of the gene(s) encoding these proteins. One pair of primers amplified a 200-bp fragment, which now has been cloned and sequenced. Within the 200-bp sequence is a motif conserved amongst dehydrins. Hybridization of the 200-bp fragment to RNA blots revealed homology to two chilling-responsive messages of 3.7 and 1.6 kb. The 200-bp fragment currently is being used to screen a cDNA library (prepared from RNA from cold acclimated blueberry floral buds) to isolate the full length cDNA clone.

Download Full-text

Growth Characterization of Low-Temperature MOCVD GaN–Comparison between N2H4and NH3–

Japanese Journal of Applied Physics ◽

10.1143/jjap.26.2067 ◽

1987 ◽

Vol 26 (Part 1, No. 12) ◽

pp. 2067-2071 ◽

Cited By ~ 30

Author(s):

Shinji Fujieda ◽

Masashi Mizuta ◽

Yoshishige Matsumoto

Keyword(s):

Low Temperature ◽

Growth Characterization

Download Full-text

334 Seasonal Characterization of the Phenolic Layer Beneath Floral Buds of Rhododendron spp.

HortScience ◽

10.21273/hortsci.34.3.500e ◽

1999 ◽

Vol 34 (3) ◽

pp. 500E-500

Author(s):

Michelle R. Salemi ◽

James D. Scott ◽

Linda Chalker-Scott

Keyword(s):

Thermal Analysis ◽

Low Temperature ◽

Fluorescence Microscopy ◽

Preliminary Analysis ◽

Cold Hardiness ◽

Floral Buds ◽

Dormant Season ◽

Cold Hardy ◽

The Relationship

It has been previously shown that dormant, cold-hardy floral buds of Azalea possess layers of highly lignified and suberized cells below the bud axis and beneath each bud scale. Two species of deciduous Azalea were analyzed bi-weekly using differental thermal analysis (DTA) throughout their dormant season to determine the development of cold hardiness as denoted by low temperature exotherms (LTEs). Other buds collected at the same time were observed using fluorescence microscopy to document the relationship between the development of the barrier and the onset of cold hardiness. Preliminary analysis showed when buds were maximally cold hardy the barrier was most intact, and as buds began to lose hardiness, the layer started to degrade. These results suggest that in fact this layer of cells does act as the long-proposed bud barrier. In a comparison between the species, the hardier species (R. japonicum) was found to have a denser layer of phenolic-rich cells compared to buds of the less hardy species (R. occidentale). This finding further supports the relationship between the layer of cells and the existence of cold hardiness in bud tissues.

Download Full-text