Abstract: The previous studies have shown that ZPC5 expressed in the ovary of the Antarctic notothenioid fishes, however, the specific function of ZPC5 is unclear until now. In order to clarify whether ZPC5 has an ability to avoid fish-freezing at the low temperature， here, we attempted the overexpression of ZPC5 in Chinese Hamster Ovary (CHO) cells, and then treated CHO cells in the low temperature, by monitoring the survival rate of CHO cells, thus we revealed about the function of zpc5 in fishes. The survival rate of CHO cells treated at 0℃ for 16 h was significantly higher than that of the mock (P<0.001), which proved that zpc5 improved the cold resistance of the cells. The Western Blot analysis showed that the zpc5 was highly expressed in CHO cells and the expression of ZPC5 was significantly increased at 0℃, which proved that the low temperature guided the expression of ZPC5. Our data suggested that ZPC5 may be involved in the resistance process of the Antarctic notothenioid fishes to the cold environment.

Key words: zona pellucida, CHO cells, Antarctic notothenioid fishes