A cold-responsive wheat (Triticum aestivum L.) gene wcor14 identified in a winter-hardy cultivar 'Mironovska 808'.
A cDNA library was constructed from a cold-acclimated winter-hardy common wheat (Triticum aestivum L.) cultivar 'Mironovska 808'. Using this library and a cold- and light-responsive barley cDNA clone cor14b as a probe, cDNAs of a homologous wheat gene wcor14 were isolated. Two identical cDNAs designated as wcor14a had an open reading frame encoding an acidic (pI = 4.71) and hydrophobic polypeptide with 140 amino acids (MW = 13.5 kDa). The deduced WCOR14a polypeptide showed 70% identity with the barley chloroplast-imported COR14b and had a nearly identical N-terminal, putative chloroplast transit peptide of 51 amino acid residues. Another cDNA clone wcor14b was assumed to encode a polypeptide WCORb which had 5 substitutions and a frame shift in the C-terminal region as compared with WCOR14a. RACE PCR, genomic PCR and Southern blot analyses suggested that wcor14 and its related sequences constitute a small multigene family with and without an intron in the hexaploid wheat genome. Northern blot analysis showed that transcripts of wcor14 accumulated within 3-6 hours of cold acclimation at 4 degrees C and the level reached a maximum at day 3. The transcripts became non-detectable within 3 hours after de-acclimation at room temperature. Contrary to the barley cor14b, a similar level of wcor14 transcripts was detected under the continuous darkness. Neither treatment with NaCl, ABA nor dehydration induced its expression. Based on these results we conclude that wcor14 is a wheat orthologue of the barley cor14b and specifically induced by low temperature.
Tsvetanov
S
S
Department of Life Science, Graduate School of Science & Technology, Kobe University, Japan.
Ohno
R
R
Tsuda
K
K
Takumi
S
S
Mori
N
N
Atanassov
A
A
Nakamura
C
C
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003080:Cold Temperature; D018076:DNA, Complementary; D018628:Gene Dosage; D018506:Gene Expression Regulation, Plant; D018740:Genetic Heterogeneity; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012621:Seasons; D014908:Triticum / Q000235:genetics*
C095314:COR14 protein, Triticum aestivum; D018076:DNA, Complementary; D006360:Heat-Shock Proteins; D010940:Plant Proteins