Differential Gene Expression of Glucose Transporter 1 (GLUT1) in Different Physiological Times in Mammary Glands of Iranian Adani Goats

Lactose determines the milk volume of mammary gland due to osmotic property. Glucose is essential precursor for lactose synthesis, which is mainly absorbed by glucose transporter 1 from blood to mammary gland. In the current study, the transcription levels of GLUT1 have been investigated during prenatal, milking and drying times in mammary glands of Adani goats having high and low breeding values. At the first, breeding values of the animals were estimated by multi-trait random regression model. Then, the samples were taken by biopsy gun and Real-Time PCR method was applied to study the expression of GLUT1. The results indicated that all fixed factors including breeding value groups, sampling times and interaction between them were significant (p<0.005). In addition, the expression of the gene only was different at milking times between two breeding value groups, so that the high breeding value group showed more transcription levels compared with the other group. The expression pattern of this gene in mammary gland was also different between two breeding value groups. Minimum expression of GLUT1 was observed at the prenatal time in high breeding value group, however low breeding value group presented the lowest expression at the milking time. The expression differences observed between the two groups in milking time could be due to the nucleotide variations in transcription factor or miRNA binding sites. Therefore, analysis of nucleotide polymorphisms need to be investigated in coding and promoter regions of this gene in further studies on Adani goats.