A new AOX homologous gene OsIM1 from rice (Oryza sativa L.) with an alternative splicing mechanism under salt stress.
A differentially expressed OsIM1 gene was isolated from rice salt-tolerant mutant M-20 by differential display. Sequence analysis revealed that the amino-acid sequence of OsIM1 showed 66% and 62% identity with PTOX from tomato ( Capsicum annuum) and AtIM from Arabidopsis, both of which encoded chloroplast-orientated terminal oxidase. Comparison of the nucleotide sequence of the OsIM1 cDNA with its genomic sequence revealed that OsIM1 genomic DNA contained nine exons and eight introns. A pseudo-transcript ( OsIM2), which probably resulted from the abnormal splicing of the OsIM1 pre-mRNA, was also identified. Southern-blot analysis showed that there existed only one copy of the OsIM1 gene in the rice genome. RFLP analysis located it on rice chromosome 3. The Northern blot revealed that OsIM1 was up-regulated by NaCl and ABA treatment. RT-PCR analysis indicated that OsIM1 and OsIM2 co-existed in the OsIM transcript pool, and the ratio of OsIM1/ OsIM2 was differentially regulated by salt stress in the salt-sensitive variety and the salt-tolerant varieties.
Kong
Jin
J
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
Gong
Ji-Ming
JM
Zhang
Zhi-Gang
ZG
Zhang
Jin-Song
JS
Chen
Shou-Yi
SY
D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D017931:DNA Primers; D040461:Gene Components; D020869:Gene Expression Profiling; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics*; D010088:Oxidoreductases / Q000235:genetics*; D010940:Plant Proteins; D012150:Polymorphism, Restriction Fragment Length; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012623:Seawater; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D000099188:Alternative Oxidase
D017931:DNA Primers; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D000099188:Alternative Oxidase