PROGRAMMED ACCUMULATION OF LEA-LIKE PROTEINS DURING DESICCATION AND COLD-ACCLIMATION OF OVERWINTERING GRAPE BUDS

Molecular investigation of the process of cold acclimation in woody pl ants has been limited by the superimposition of dormancy-related event s on the process of cold tolerance development, To address this limita tion, we have used the grape Vitis labruscana L. cv. Concord to develo p a system in which the developmental programme of dormancy can be ind uced seperately from cold acclimation, Using this system we have chara cterized differential accumulation of several proteins in grape buds d uring the normally superimposed endodormancy and cold acclimation prog rammes, and in buds which have entered only the endodormancy programme , A set of 47 kD proteins accumulated during endodormancy without cold acclimation to a level similar to that found in endodormant and cold- acclimated buds, but without any associated increase in bud cold-accli mation level, However, a 27 kD LEA-like protein accumulated only in co ld acclimated buds, We conclude that expression of the 47 kD glycoprot ein is endodormancy-related, but is not strictly related to the develo pment of cold acclimation, while the 27 kD protein appears to be more specific to cold acclimation, In addition to strengthening the associa tion of LEA-like proteins with cold acclimation, this system allows mo re specific assessment of cold acclimation-associated phenomena in ove rwintering buds.