Int. J. Dev. Biol. 55: 327 - 334 (2011)
doi: 10.1387/ijdb.103270jy
© UPV/EHU Press

Dynamic expression of manganese superoxide dismutase during mouse embryonic organogenesis

Jung-Min Yon1, In-Jeoung Baek2, Beom Jun Lee1, Young Won Yun1 and Sang-Yoon Nam*,1

1College of Veterinary Medicine and Research Institute of Veterinary Medicine (RIVM), Chungbuk National University, Cheongju, South Korea and 2Laboratory of Mammalian Molecular Genetics, Department of Biochemistry, College of Science, Yonsei University, Seoul, South Korea

ABSTRACT The balance between reactive oxygen species production and antioxidant defense enzymes in embryos is necessary for normal embryogenesis. To determine the dynamic expression profile of manganese superoxide dismutase (MnSOD) in embryos, which is an essential antioxidant enzyme in embryonic organogenesis, the expression level and distribution of MnSOD mRNA and protein were investigated in mouse embryos, as well as extraembryonic tissues on embryonic days (EDs) 7.5-18.5. MnSOD mRNA levels were remarkably high in extraembryonic tissues rather than in embryos during these periods. MnSOD protein levels were also higher in extraembryonic tissues than in embryos until ED 16.5, but the opposite trend was found after ED 17.5. MnSOD mRNA was observed in the chorion, allantois, amnion, ectoderm, ectoplacental cone and neural fold at ED 7.5 and in the neural fold, gut, ectoplacental cone, outer extraembryonic membranes and primitive heart at ED 8.5. After removing the extraembryonic tissues, the prominent expression of MnSOD mRNA in embryos was seen in the sensory organs, central nervous system and limbs on EDs 9.5-12.5 and in the ganglia, spinal cord, sensory organ epithelia, lung, blood cells and vessels, intestinal and skin epithelia, hepatocytes and thymus on EDs 13.5-18.5. Strong MnSOD immunoreactivity was observed in the choroid plexus, ganglia, myocardium, blood vessels, heapatocytes, pancreatic acinus, osteogenic tissues, brown adipose tissue, thymus and skin. These findings suggest that MnSOD is mainly produced from extraembryonic tissues and then may be utilized to protect the embryos against endogenous or exogenous oxidative stress during embryogenesis.

Keywords:

MnSOD, oxidative stress, organogenesis, mouse embryo, expression profile

*Corresponding author e-mail: synam@cbu.ac.kr