| The localization and expression of early growth response 2 and insulin-like growth factor binding protein in the skin tissue of Merinos and local sheep and the overexpression of Krox20 in cultured sheep fibroblasts were studied to explore the correlation between Krox20 and wool bending and the regulatory relationship between Krox20 and IGFBP5.Three merinos and three local sheep were selected.The immunohistochemistry,Quantitative Real-time PCR and Western blot were used to study expression of Krox20 and IGFBP5 m RNA and protein.Sheep fibroblasts were cultured in vitro,and the regulation of IGFBP5 was analyzed by cell transfection technique using p EGFP-N1 as a vector and overexpressing Krox20.The results showed: in the skin tissue of the back of the merinos and local sheep,Krox20 and IGFBP5 protein were strongly expressed in the hair matrix,inner and outer root sheath,epidermis,hair shaft and sebaceous gland,and were weakly expressed in the dermal papilla.The expression levels of Krox20 and IGFBP5 m RNA in the back skin tissues of merinos were higher than those of local sheep,and the expression level of Krox20 m RNA in the merinos was 2.44 times higher than that of the local sheep,and the difference was extremely significant(**P<0.01);The expression level of IGFBP5 m RNA in the merinos was 3.76 times higher than that of the local sheep,and the difference was extremely significant(**P<0.01).The expression levels of Krox20 and IGFBP5 protein in merinos were higher than that of local sheep,and the expression level of Krox20 protein in the merinos was 1.53 times higher than that of the local sheep,and the difference was extremely significant(**P<0.01);The expression level of Krox20 protein in the merinos was 1.42 times higher than that of the local sheep,and the difference was significant(**P<0.05).After overexpressing Krox20,compared with the p EGFP-N1 empty control group,the m RNA and protein expression levels of Krox20 and IGFBP5 were increased.The results showed that IGFBP5 was the first marker gene for hair bending,Krox20 had a positive regulation effect on IGFBP5,and Krox20 promoted the formation of wool bending. |
