The Expression Of FoxO1 、MyHC Gene Family And Its Effect On Meat Quality In Bamei And Sunit Sheep

The expression pattern of FoxOl and MyHC gene family were analyzed in longissimus dorsi (B), triceps brachii (Q), and biceps femoris (H) in 46 Bamei and 36 sunit sheep in different month ages. Real-time PCR tecnology was applied to explor the pattern of gene expression, expression different in two breeds and the correlation of genes. The shearing force, color and pH were measured to detecte the correlation between expression and meat quality.The results shown as follows:(1) The laws of FoxOl and MyHC Ⅱ x expression quantity were the type of "M" in Bamei sheep. There were no significant rules about the expression of MyHC Ⅰ and MyHC Ⅱ a in both two breeds. MyHC Ⅱ b expression of Bamei increased at the earlier stage and decreased at the later stage, but FoxOl, MyHC Ⅱ b and MyHC Ⅱ x of sunit shown contrarily change. There was a common law that the expression of triceps brachii and biceps femoris were always higher than longissimus dorsi. (2) The sunit MyHC Ⅱb expression of 5-month biceps femoris, 6-month triceps brachii and 12-month longissimus dorsi and biceps femoris were significant higher than Bamei MyHC Ⅱb expression (p< 0.05). Other genes had significant differences in two breeds, but didn’t have laws. (3) In two breeds, the expression of FoxOl had positive correlation with the expression of MyHC gene family, and particllarly shown a high correlation with MyHC Ⅱ b and MyHC Ⅱ x (r> 0.6). What’s more, the expression of MyHC Ⅰ and MyHC Ⅱ a, MyHC Ⅱb and MyHC Ⅱ x shown high correlation (r>0.62).In Bamei sheep and sunit sheep, the mRNA expression of FoxOl and MyHC gene family shown significant correlation with b, L and pH1 in some parts (p<0.05). Although there were no significant correlation in MyHC Ⅱ a and pH2, the expression of MyHC Ⅱ a shown high correlation with pH2 of Bamei sheep, and all the correlation indexes were higher than 0.63. When muscle pH reduced too fast, it might lead to poor meat quality. In order to improve meat quality, it was possible to control the expression of MyHC Ⅱ a, and then ease rapid drop in pH. Furthermore, in sunit, the expression of MyHC Ⅱ b shown high correlation with shearing force, and mean correlation index was 0.54. As the expression of MyHC Ⅱ b increased, shearing force increased. It meant expression of MyHC Ⅱb had a negative effect on tenderness.