title: Fatty acid elongase 6 plays a role in the synthesis of long-chain fatty acids in goat mammary epithelial cells.
abstract: In nonruminants, it is well established that elongation of very long-chain fatty acid-like fatty acid elongase 6 (ELOVL6) catalyzes the synthesis of C18:0 from C16:0 in lipogenic tissues like adipose and liver. However, the role of ELOVL6 in regulating lipid metabolism in ruminant mammary gland remains unknown. In the present study, ELOVL6 was overexpressed or knocked down via adenoviral transfection to assess its role in goat mammary epithelial cells. Results revealed that ELOVL6 overexpression had a weak effect on the expression of genes related to triacylglycerol (TAG) synthesis and desaturation. Overexpression of ELOVL6 increased the content of C18:0 at the expense of C16:0, and increased the elongation index of C16:0. Overexpression of ELOVL6 had no significant effect on the elongation index of C16:1n-7 and the desaturation indices of C16:0 and C18:0. Knockdown of ELOVL6 had a negative effect on mRNA expression of the esterification genes GPAM and diacylglycerolacyltransferase 2 (DGAT2) and TAG concentration; however, it increased the concentration of C16:0 and decreased C18:1n-7 and C18:1n-9 in goat mammary epithelial cells. Accordingly, downregulation of ELOVL6 significantly decreased the elongation indices of C16:0 and C16:1n-7. The lack of change in the desaturation indices of C16:0 and C18:0 upon knockdown of ELOVL6 was consistent with the minor change in SCD1 expression. In conclusion, these are the first results highlighting an important role of ELOVL6 in long-chain fatty elongation and TAG synthesis in ruminant mammary cells.
authors.affiliation: Key Laboratory of Silkworm Bioreactor and Biomedicine of Zhejiang Province, College of Life Science, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, 310018, P. R. China.
authors.forename: H B
authors.initials: HB
authors.lastname: Shi
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China; Jibei Middle School, Jinan, Shandong, 251400, P. R. China.
authors.forename: M
authors.initials: M
authors.lastname: Wu
authors.affiliation: Key Laboratory of Sichuan Province for Qinghai-Tibetan Plateau Animal Genetic Reservation and Exploitation, Southwest University for Nationalities, Chengdu, 610041, P. R. China.
authors.forename: J J
authors.initials: JJ
authors.lastname: Zhu
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China.
authors.forename: C H
authors.initials: CH
authors.lastname: Zhang
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China.
authors.forename: D W
authors.initials: DW
authors.lastname: Yao
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China. Electronic address: luojun@nwsuaf.edu.cn.
authors.forename: J
authors.initials: J
authors.lastname: Luo
authors.affiliation: Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801. Electronic address: jloor@illinois.edu.
authors.forename: J J
authors.initials: JJ
authors.lastname: Loor
mesh_terms: D000123:Acetyltransferases / Q000235:genetics / Q000502:physiology*; D000818:Animals; D051048:Diacylglycerol O-Acyltransferase; D004847:Epithelial Cells / Q000378:metabolism*; D004951:Esterification / Q000235:genetics; D000081031:Fatty Acid Elongases; D005227:Fatty Acids / Q000096:biosynthesis*; D005260:Female; D055785:Gene Knockdown Techniques / Q000662:veterinary; D006041:Goats; D008321:Mammary Glands, Animal / Q000166:cytology*; D012333:RNA, Messenger / Q000378:metabolism; D014280:Triglycerides / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D005227:Fatty Acids; D012333:RNA, Messenger; D014280:Triglycerides; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases; D051048:Diacylglycerol O-Acyltransferase
keywords: elongase; fatty acid composition; lactation; milk fat