Ectopic expression of a cold-responsive OsAsr1 cDNA gives enhanced cold tolerance in transgenic rice plants.
The OsAsrt cDNA clone was isolated from a cDNA library prepared from developing seed coats of rice (Oryza sativa L.). Low-temperature stress increased mRNA levels of OsAsr1 in both vegetative and reproductive organs. In situ analysis showed that OsAsr1 transcript was preferentially accumulated in the leaf mesophyll tissues and parenchyma cells of the palea and lemma. For transgenic rice plants that over-expressed full-length OsAsr1 cDNA in the sense orientation, the Fv/Fm values for photosynthetic efficiency were about 2-fold higher than those of wild type-segregating plants after a 24-h cold treatment. Seedlings exposed to prolonged low temperatures were more tolerant of cold stress, as demonstrated during wilting and regrowth tests. Interestingly, OsAsr1 was highly expressed in transgenic rice plants expressing the C-repeat/dehyhdration responsive element binding factor 1 (CBF1), suggesting the regulation of OsAsr1 by CBF1. Taken together, we suggest that OsAsr1 gene play an important role during temperature stress, and that this gene can be used for generating plants with enhanced cold tolerance.
Kim
Soo-Jin
SJ
Department of Life Science, Sogang University, Seoul, Korea.
Lee
Sang-Choon
SC
Hong
Soon Kwan
SK
An
Kyungsook
K
An
Gynheung
G
Kim
Seong-Ryong
SR
D000595:Amino Acid Sequence; D015139:Blotting, Southern; D003080:Cold Temperature; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics* / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D015996:Survival Rate
D018076:DNA, Complementary; D018744:DNA, Plant; D010940:Plant Proteins