title: Molecular and expression analysis of manganese superoxide dismutase (Mn-SOD) gene under temperature and starvation stress in rotifer Brachionus calyciflorus.
abstract: Superoxide dismutase (SOD) is an important antioxidant enzyme that protects organs from damage by reactive oxygen species. We cloned cDNA encoding SOD activated with manganese (Mn-SOD) from the rotifer Brachionus calyciflorus Pallas. The full-length cDNA of Mn-SOD was 1,016 bp and had a 669 bp open reading frame encoding 222 amino acids. The deduced amino acid sequence of B. calyciflorus Mn-SOD showed 89.1, 71.3, and 62.1 % similarity with the Mn-SOD of the marine rotifer Brachionus plicatilis, the nematode Caenorhabditis elegans, and the fruit fly Drosophila melanogaster, respectively. The phylogenetic tree constructed based on the amino acid sequences of Mn-SODs from B. calyciflorus and other organisms revealed that this rotifer is closely related to nematodes. Analysis of the mRNA expression of Mn-SOD under different conditions revealed that expression was enhanced 5.6-fold (p < 0.001) at 30 °C after 2 h, however, low temperature (15 °C) promoted Mn SOD temporarily (2.5-fold, p < 0.001) and then decreased to normal level (p > 0.05). Moderate starvation promoted Mn-SOD mRNA expression (p 12 < 0.01, p 36 < 0.05), which reached a maximum value (15.3 times higher than control, p 24 < 0.01) at 24 h. SOD and CAT activities also elevated at the 12 h-starved group. These results indicate that induction of Mn-SOD expression by stressors likely plays an important role in aging of B. calyciflorus.
authors.affiliation: Jiangsu Province Key Laboratory for Biodiversity & Biotechnology and Jiangsu Province Key Laboratory for Aquatic Live Food, School of Biological Sciences, Nanjing Normal University, Nanjing 210046, Jiangsu, People's Republic of China.
authors.forename: Jianghua
authors.initials: J
authors.lastname: Yang
authors.forename: Siming
authors.initials: S
authors.lastname: Dong
authors.forename: Huanxi
authors.initials: H
authors.lastname: Zhu
authors.forename: Qichen
authors.initials: Q
authors.lastname: Jiang
authors.forename: Jiaxin
authors.initials: J
authors.lastname: Yang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D010802:Phylogeny; D012403:Rotifera / Q000235:genetics* / Q000502:physiology; D013217:Starvation; D013482:Superoxide Dismutase / Q000235:genetics* / Q000302:isolation & purification; D013696:Temperature
chemical_list: D018076:DNA, Complementary; D013482:Superoxide Dismutase