PLANT PHYSIOLOGY , Vol 104, Issue 2 445-452, Copyright © 1994 by American Society of Plant Biologists
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MOLECULAR BIOLOGY AND GENE REGULATION |
Transcripts Accumulating during Cold Storage of Potato (Solanum tuberosum L.) Tubers Are Sequence Related to Stress-Responsive Genes
J. van Berkel, F. Salamini and C. Gebhardt
Max-Planck-Institut fur Zuchtungsforchung, Carl-von-Linne-Weg 10, D-50829 Koln, Germany
During the adaptation of plants to low temperature, changes in gene
expression can be induced in a variety of tissues.
Low-temperature-regulated gene expression was studied in cold-stored potato
(Solanum tuberosum L.) tubers by two-dimensional electrophoresis of in
vitro translation products. As a response to cold treatment, the relative
amount of mRNA encoding at least 26 polypeptides changed. By differential
screening of a cDNA library, 16 clones corresponding to cold-inducible
transcripts were isolated. They were classified into four
non-cross-hydridizing groups.RNA hybridizations using representative clones
from each group revealed different temporal accumulation patterns for the
cold-inducible transcripts. mRNAs homologous to the cDNA clones were first
detectable after 1 to 3 d of cold treatment, and the highest level of
expression was reached after 3 to 7 d. Transcripts corresponding to cDNA
clones Cl13 and Cl19 were transiently expressed, whereas the steady-state
level remained high for cDNA clones Cl7 and Cl21 during the cold storage
period of 4 weeks.The DNA sequences of two cDNA clones, Cl7 and Cl19, have
been determined. The polypeptide predicted from the DNA sequence of Cl19 is
sequence related to small heat-shock proteins from other plant species. The
deduced protein sequence of Cl7 exhibits strong homology to the
dehydrin/RAB group of dehydration stress- and abscisic acid-inducible
polypeptides and to cold-induced proteins from Arabidopsis and spinach.
