【摘要】 为明确山羊边缘区B细胞和B1细胞特异性蛋白(MZB1)在山羊的肌内脂肪分化中起到的调控作用，首先克隆山羊MZB1基因实际序列，并对序列进行生物信息学分析获得相关生物学特征;随后利用实时荧光定量PCR(q PCR)绘制山羊MZB1组织与细胞时序表达谱;最后转染山羊MZB1过表达质粒至细胞内并进行诱导分化，通过形态学观察及q PCR等试验确定过表达山羊MZB1基因对该分化过程的影响。结果表明:山羊MZB1基因序列全长共计860 bp,CDS区长度为570 bp;山羊MZB1基因共编码189 aa;山羊MZB1蛋白属于酸性蛋白且带负电，该蛋白在细胞中可以稳定存在。山羊心脏、肝脏等8个组织均检测到山羊MZB1表达且在脾脏中表达量最高。在油酸诱导山羊肌内脂肪细胞分化72 h后，山羊MZB1表达量极显著高于诱导分化前。山羊MZB1过表达增加山羊肌内脂肪细胞中的脂滴数量和大小; FASN、PPARγ、C/EBPα、SREBP1、C/EBPβ表达水平极显著上调。以上结果表明，MZB1促进山羊肌内脂肪细胞分化，且这种促进作用可能通过上调脂肪分化标志基因PPARγ、C/EBPα、C/EBPβ，脂肪酸合成标志基因SREBP1、FASN的表达来实现。更多还原

【Abstract】 In order to clarify the regulatory role of marginal zone B and B1 cell specific protein(MZB1) in intramuscular adipose differentiation of goats,the study first cloned the full-lenth sequence of goat MZB1 gene and analyzed the sequence to obtain the relevant biological characteristics; then used Real-time Quantitative PCR(qPCR) to construct the expression profile of goat MZB1 in tissues and cells; finally,the goat MZB1 overexpression plasmid was transfected into the target cells,followed by differentiation induction; the effects of MZB1 overexpression on the differentiation process were evaluated through morphological analysis and qPCR. The results showed that the goat MZB1 gene sequence was 860 bp in length,including 570 bp CDS region,encoding 189 amino acids; goat MZB1 protein was not only acidic but also negatively charged,which could be stably existed in the cells. Goat MZB1 expression was detected in eight tissues,including the heart and the liver,and the highest expression was found in the spleen. The expression of MZB1 in goat intramuscular adipocytes after 72 h of oleic acid-induced differentiation was significantly higher than that before oleic acid-induced differentiation. Goat MZB1 overexpression increased the number and size of lipid droplets in goat intramuscular adipocytes; the expression levels of FASN,PPARγ,C/EBPα,SREBP1,and C/EBPβ were highly significantly upregulated. The above results suggest that MZB1 plays a positive regulatory role in goat intramuscular adipocyte differentiation,and this positive regulation may be achieved by increasing the expression of the adipose differentiation marker genes PPARγ,C/EBPα,C/EBPβ,and the fatty acid synthesis marker genes SREBP1 and FASN.更多还原