title: The effect of heat stress on gene expression and synthesis of heat-shock and milk proteins in bovine mammary epithelial cells.
abstract: In this study, bovine mammary epithelial cells were used to study stress responses after cells were exposed to 42°C for 0.5, 1, 3, 5, 8 or 12 h, and 38°C as control. The transcription of the genes (HSP27, HSP70 and HSP90) of heat shock protein (Hsp) was significantly enhanced under heat stress (HS). The peak transcription of HSP70 was 14 times the control at 1 h. Expression of proteins Hsp27 and Hsp70 was gradually increased under HS, with rapid deposition of Hsp70 in epithelial cells. The major milk protein genes of β-casein (CSN2) and butyrophilin (BTN1A1) were down-regulated and the synthesis of total caseins was decreased. After the cells were under HS (42°C) for 1 or 5 h, the cells were cultured at 38°C for 1, 6, 12 or 24 h for recovery. When the cells were cultured at 38°C for 24 h after HS for 1 h, the transcription of HSP70, HSP90, CSN2 and BTN reached normal levels. Our results suggest that HS initiated Hsp synthesis and decreased the milk protein synthesis. Hsp70 is extremely sensitive to HS and mainly responsible for mammary cell protection from HS.
authors.affiliation: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|Ministry of Agriculture-Milk and Dairy Product Inspection Center, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Han
authors.initials: H
authors.lastname: Hu
authors.affiliation: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|Ministry of Agriculture-Milk and Dairy Product Inspection Center, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Yangdong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|Ministry of Agriculture-Milk and Dairy Product Inspection Center, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zheng
authors.affiliation: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|Ministry of Agriculture-Milk and Dairy Product Inspection Center, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.|Ministry of Agriculture-Milk and Dairy Product Inspection Center, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism*; D018869:Heat-Shock Response; D006358:Hot Temperature; D006801:Humans; D008321:Mammary Glands, Animal / Q000378:metabolism*; D008894:Milk Proteins / Q000235:genetics* / Q000378:metabolism*
chemical_list: D006360:Heat-Shock Proteins; D008894:Milk Proteins
keywords: casein; heat shock protein; heat stress; mammary epithelial cell