[Effect of zinc deficiency and zinc replenishment on HOX3.5 gene expression in mouse embryos]

The effect of zinc deficiency and zinc replenishment on HOX3.5 gene expression in mouse embryos was investigated. Sixty Kunming female mice (25-30 g) were divided into three groups: zinc-deficient groups (ZD), zinc-replenished group (ZR) and zinc normal controlled group (ZN). ZD mice fed with ZD diet (Zn 3.0 +/- 0.5 mg/kg), ZN mice fed with ZN diet (Zn 30 mg/kg), and ZR mice fed with ZD diet at first and then with ZN diet from the 7th day of pregnancy. After feeding different diet for 25 days, the mice were made to copulate (female: male = 2:1). At the 12th day of pregnancy, the mice were killed and the embryos were stored at -70 degrees C. The content of mRNA of HOX3.5 in the embryos were determined by in situ hybridization with digxigenin-labeled cDNA probes. The result showed that the expression on area density and L-density (average optical density) of Hox3.5 in ZD and ZR groups were decreased in comparing with those in ZN group (P < 0.05). It was suggested that the decreased HOX3.5 gene expression by zinc deficiency might influence the normal growth of mouse embryos, and this effect might occurr in the early stage of embryo development, which can not be prevented by replenishing zinc at the 7th day of pregnancy.