高温诱导体外培养奶牛乳腺上皮细胞的应激响应  

Responses of Cultrued Bovine Mammary Epithelial Cells to Heat Stress

作　　者：胡菡[1,2] 王加启[1,2] 李发弟[2] 卜登攀[2] 周凌云[2] 崔瑞莲[2] 

机构地区：[1]甘肃农业大学动物科学技术学院,兰州730070 [2]中国农业科学院北京畜牧兽医研究所动物营养学国家重点实验室,北京100193

出　　处：《农业生物技术学报》2011年第2期287-293,共7页Journal of Agricultural Biotechnology

基　　金：国家"十一五"科技支撑计划项目(No.2006BAD04A14)资助

摘　　要：实验以体外培养的奶牛乳腺上皮细胞为模型,研究不同时间高温(42℃)热处理对细胞热休克蛋白HSP、细胞凋亡、乳脂肪和乳蛋白合成相关基因mRNA表达丰度的影响。结果发现,热休克转录子hsf-1和热休克蛋白基因hsp27、hsp70和hsp90在高温处理0.5h后mRNA表达上调,其中hsp70转录水平有急剧上调过程,且随热处理时间延长均表现出先上升后下降的趋势;标志细胞凋亡的Bax基因从处理的0.5h开始mRNA表达下调,随后升高;但细胞凋亡Bcl-2mRNA表达上调;在检测的热处理过程中,αS1-酪蛋白(CSN1S1)基因转录先上调后下降,而β-酪蛋白(CSN2)和嗜乳脂蛋白(BTN)基因转录均下调;与脂肪酸合成和调控相关的基因乙酰辅酶A羧化酶(ACACA)、过氧化物酶激活受体-γ(PPARG)和固醇调节元件转录因子-1(SREBF-1)基因表达显著上调,而过氧化物酶激活受体-α(PPARA)基因mRNA转录没有明显变化。本实验结果证明热应激诱导了奶牛乳腺上皮细胞的应激反应,对细胞的乳蛋白和乳脂肪合成功能产生了显著影响,细胞产生热耐受。The experiment was conducted to study the response of bovine mammary epithelial cells induced by heat stress.Bovine mammary epithelial cells were exposed to 42 ℃ as the heat stress model and 38℃ as control,the transcription of targeted genes including heat shock proteins（HSPs） family,apoptosis,mlik protein and fatty acid biosynthesis,were detected by RT-qPCR.Results showed that the mRNA expression level of hsp27,hsp70 and hsp90,and heat shock factor-1（hsf-1） increased after 0.5 h at 42 ℃,and among them hsp70 increased sharply,then decreased with the extended time of treatment.The apoptosis genes Bcl-2 and Bax had different transcription,Bcl-2 upregulated during 24 h,while Bax upregulated first and downregulated later.Heat stress decreased the mRNA level of milk protein and fatty acids genes（α-and β-casein（CSN2）,butyrophilin（BTN）,and fatty acid synthase）,increased transcription of fatty acid biosynthesis correlative genes（acetyl CoA carboxylase（ACACA）,proxiomepro liferater activatedreceptor-gama（PPARG）,and sterol response element binding protein（SREBF-1））,but did not influence the expression of roxiomepro liferater activatedreceptor-alfa（PPARA）.It is suggested that heat shock induced the stress responses of bovine mammary peithelial cells,remarkably impacted the secretion of milk protein and fat,and arose tolerance of cell itself.

关 键 词：奶牛乳腺上皮细胞 热应激 热休克蛋白 酪蛋白 乙酰辅酶A羧化酶 嗜乳脂蛋白 脂肪酸 

分 类 号：S827.1[农业科学—畜牧学]