生物钟基因BMAL1过表达对山羊子宫内膜上皮细胞凋亡的影响OA北大核心CSTPCD

As an endogenous timekeeping system,the circadian clock system plays an important role in regulating behavioral activities and physiological functions in mammals.To investigate the role of the core clock gene brain and muscle arnt-like protein 1(BMAL1)in apoptosis of goat endometrial epithelial cells(GEECs),the CDS of BMAL1 gene was cloned from 24-month-old goat(Capra hircus)uterine tissues,and the physicochemical properties of the gene and its coding protein were analyzed and predicted using the bioinformatics software;the expression patterns of BMAL1 were detected using qPCR in different tissues of goats as well as GEECs after synchronization.The effect of BMAL1 gene overexpression on GEECs apoptosis was detected by flow cytometry,qPCR,and Western blot(WB).The results showed that the expression of BMAL1 gene showed significant diurnal differences in various tissues and at different time points.The total length of CDS fragment of goat BMAL1 gene was 1 881 bp,which was highly conserved in mammals.And protein encoded by BMAL1 could participate in multiple physiological processes by interacting with proteins such as circadian locomotor output cycles kaput(CLOCK),nuclear receptor subfamily 1,group D,member 1(NR1D1),and casein kinase 1δ(CSNK1D).Flow cytometry results showed that BMAL1 overexpression significantly reduced the apoptosis rate in GEECs(P＜0.05).qPCR and Western blot results showed that BMAL1 overexpression led to a significant decrease in the expression levels of pro-apoptotic genes BCL2-associated X protein(BAX)and tumor suppressor gene P53 in both mRNA and protein,and the expression of apoptosis suppressor gene B cell lymphoma-2(BCL-2)significantly elevated(P＜0.05).This study provides a preliminary basis for analyzing the molecular regulatory mechanism of the ruminant circadian clock system and further exploring the biological functions of the goat BMAL1 gene.