Cloning and characterization of a novel splicing isoform of the iron-superoxide dismutase gene in rice (Oryza sativa L.).
Superoxide dismutases (SODs) are ubiquitous metalloenzymes in aerobic organisms that play a crucial role in protecting organisms against ROS. Here, we report the molecular cloning and functional characterization of a novel alternatively spliced variant of the iron-superoxide dismutase gene, OsFe-SODb, from a rice panicle cDNA library. The alternative splicing event occurred in the fourth exon of the OsFe-SOD gene, and led to the translation of two isoforms of different sizes. The 5' flanking region of the OsFe-SOD was cloned and many cis-acting regulatory elements were found that are involved in light responsiveness, including a G-box and an I-box. RT-PCR analysis showed that the two alternative forms of OsFe-SOD were expressed in both the vegetative and reproductive tissues of Cpslo17. Moreover, accumulation of both isoforms was upregulated by light induction. In addition, the alternative splicing of OsFe-SOD mRNA was sensitive to low temperature. High yield production of the two recombinant OsFe-SOD isoforms was achieved in Escherichia coli. SOD assays showed that C-terminal truncation in OsFe-SODb did not result in a loss of SOD enzyme activity.
Feng
Wang
W
The State Key Laboratory for Biocontrol and The Key Laboratory of Gene Engineering of Ministry of Education, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China.
Hongbin
Wang
W
Bing
Liu
L
Jinfa
Wang
W
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013482:Superoxide Dismutase / Q000737:chemistry / Q000235:genetics*
D017931:DNA Primers; D018076:DNA, Complementary; D013482:Superoxide Dismutase