Study On The Function Of CRY1 Gene In Yak

Yak(Bos grunniens),a special species in Qinghai and Tibet Plateau,has very important economic and scientific research value.However,its production performance and reproductive breeding rate are low,which greatly affects the reproductive performance of yak.The previous study found that the CRY1 gene(Cryptochrome 1)is closely related to the secretion of the steroid hormones.CRY1 is a kind of flavin protein sensitive to blue light and near-ultraviolet light.It is widely found in higher eukaryotes and it is one of the mammalian clock genes.It is both a photoreceptor and a circadian clock.The effector is delivered to regulate its physiology,biochemistry and behavior.In this study,the CRY1 gene of yak was cloned by RT-PCR.The expression of CRY1 gene in different tissues and organs of yak were detected by the Quantitative Real-time PCR,immunohistochemistry and Western blot.The yak testis support cells were used as the research object,and the function of CRY1 gene was verified by transfection of siRNA.The results showed as follows.The results showed that the CRY1 gene CDS has a full length of 1712 bp,an ORF of 1257 bp,encoding a total of 418 amino acid residues,no transmembrane domain,and the encoded protein is a soluble protein.The yak CRY1 gene was expressed in different tissues(testis,ovary,heart,liver,spleen,lung,kidney and muscle),and its expression in muscle was significantly higher than that in other tissues(P<0.05).The mRNA and protein of CRY1 gene in yak were expressed on the gonad axis(hypothalamus,pituitary,testis and pineal gland),and the expression in pineal gland was significantly higher than that in other tissues(P<0.01).The mRNA and protein of CRY1 gene in yak were expressed in the testes of different-years-old of yak(30 days old,2 years old,4 years old and 6 years old),and the expression level was gradually increased with age(P<0.05).After 4 years of age,the expression level tends to be stable.The expression trend of MTNR1 a gene is basically the same as that of CRY1 gene.The expression level of CRY1 mRNA and protein in yak testis-supporting cells transfected with siRNA sequence was significantly lower than that in the negative control group(P<0.05),and the expression level was the lowest at 48 hours after transfection.The expression level of the MTNR1 a gene decreases as the CRY1 gene is knocked down.In conclusion,the CRY1 gene may play an important role in the reproductive processes such as yak reproductive,providing a basis for further study of the biological function of the yak rhythm gene CRY1 and its role in reproductive physiology regulation.