Effect of in ovo folic acid injection on hepatic IGF2 expression and embryo growth of broilers  

作　　者：Yanli Liu Lihui Zhi Jing Shen Shizhao Li Junhu Yao Xiaojun Yang 

机构地区：[1]College of Animal Science and Technology,Northwest A&F University [2]School of Mathematics and Computer Science,Shan Xi Normal University

出　　处：《Journal of Animal Science and Biotechnology》2017年第1期196-204,共9页畜牧与生物技术杂志（英文版）

基　　金：supported by the Natural Science Foundation of China (No. 31272464);the Program for New Century Excellent Talents (NCET-12-0476);the Program for Shaanxi Science & Technology (2014 K01-18-02, 2015NY149, 2015KTCQ02-19)

摘　　要：Background： Insulin-like factor 2（IGF2） plays an important role in embryonic growth process by modulating intermediary metabolism and cell proliferation. Folic acid is involved in one carbon metabolism and contributes to DNA methylation which is related to gene expression. The purpose of this study was to explore whether folic acid could regulate IGF2 expression via epigenetic mechanism and further promote embryonic growth of new-hatched broilers.Methods： In the present study, 360 fertile eggs were selected and randomly assigned to four treatments. On11 embryonic day of incubation（E11）, 0, 50, 100 and 150 μg folic acid were injected into eggs respectively.After hatched, growth performance of broilers were calculated. Hepatic IGF2 expression, methylation level and chromatin structure of promoter region were analyzed.Results： Results have showed that IGF2 expression was up-regulated in 150 μg folic acid group（P 〈 0.05） and other two dose of folic acid did not affect gene expression（P 〉 0.05）. Meanwhile, methylation level of IGF2 promoter were lower in 100 and 150 μg groups, which was consistent with lower expression of DNA methyltransferase1（DNMT1）（P 〈 0.05）. What＇s more, chromatin looseness of IGF2 promoter was higher in 150 μg group than control group（P 〈 0.05）. Further, birth weight（BW）, liver and bursa index of new-hatched chickens in 150 μg folic acid group were higher than the other groups（P 〈 0.05）. There were positive correlations between hepatic IGF2 expression and BW and organs index（P 〈 0.05）.Conclusion： In conclusion, our data have demonstrated that 150 μg folic acid injection on E11 could up-regulate IGF2 expression by modulating DNA hypomethylation and improving chromatin accessibility in the gene promoter region,and ulteriorly facilitate embryonic growth and organ development of broilers.Background： Insulin-like factor 2（IGF2） plays an important role in embryonic growth process by modulating intermediary metabolism and cell proliferation. Folic acid is involved in one carbon metabolism and contributes to DNA methylation which is related to gene expression. The purpose of this study was to explore whether folic acid could regulate IGF2 expression via epigenetic mechanism and further promote embryonic growth of new-hatched broilers.Methods： In the present study, 360 fertile eggs were selected and randomly assigned to four treatments. On11 embryonic day of incubation（E11）, 0, 50, 100 and 150 μg folic acid were injected into eggs respectively.After hatched, growth performance of broilers were calculated. Hepatic IGF2 expression, methylation level and chromatin structure of promoter region were analyzed.Results： Results have showed that IGF2 expression was up-regulated in 150 μg folic acid group（P 〈 0.05） and other two dose of folic acid did not affect gene expression（P 〉 0.05）. Meanwhile, methylation level of IGF2 promoter were lower in 100 and 150 μg groups, which was consistent with lower expression of DNA methyltransferase1（DNMT1）（P 〈 0.05）. What＇s more, chromatin looseness of IGF2 promoter was higher in 150 μg group than control group（P 〈 0.05）. Further, birth weight（BW）, liver and bursa index of new-hatched chickens in 150 μg folic acid group were higher than the other groups（P 〈 0.05）. There were positive correlations between hepatic IGF2 expression and BW and organs index（P 〈 0.05）.Conclusion： In conclusion, our data have demonstrated that 150 μg folic acid injection on E11 could up-regulate IGF2 expression by modulating DNA hypomethylation and improving chromatin accessibility in the gene promoter region,and ulteriorly facilitate embryonic growth and organ development of broilers.

关 键 词：Broiler Chromatin structure Folic acid Insulin-like growth factor 2 Methylation 

分 类 号：S831[农业科学—畜牧学]