VARIATION IN GENE EXPRESSION OF LEPTIN AND INSULIN LIKE GROWTH FACTOR (IGF) GENES IN RESPONSE TO SEASONAL DIFFERENCES IN CAMEL
Abstract
Epigenetic regulation of gene expression has proven to be a good biomarker for gene expression profiling. In the present study, Real-time PCR and Methylation level were performed to compare the levels of Leptin and IGF gene expression on 20 Maghrabi female camels exposed to variable temperatures (winter and summer). The results showed that hypermethylation prevailed in winter than in summer. A different profile was obtained in summer for both the two genes under study, as the hypomethylation was globally predominant. It could be concluded that the seasonal variations and conditions of the external environment in which the animal lives affect the various proteins in gene expression for each of the two genes (leptin and insulin-like growth factor). Where there is an inverse relationship between gene expression and methylation level. This means that the drop of temperature in winter leads to an increase of the methylation level (hypermethylation); resulting in a decrease in gene expression (down-regulation). On the other hand, temperature was rising during the summer, leads to the decrease of methylation level (hypomethylation) resulting in an increase in gene expression (upregulation) of the above-mentioned genes.References
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