title: Association of protein expression in isolated milk epithelial cells and cis-9, trans-11 conjugated linoleic acid proportions in milk from dairy cows.
abstract: BACKGROUND
  The effects of the individual variation among dairy cows on the synthesis of cis-9, trans-11 conjugated linoleic acid (CLA) are still not well characterised. Therefore, the protein expression profiles of isolated milk epithelial cells (MECs) were detected by two-dimensional electrophoresis and their correlation with the various proportion of cis-9, trans-11 CLA were evaluated.
  
  
  RESULTS
  Although animals were offered the same diet, the proportion of cis-9, trans-11 CLA in group High (1.02 ± 0.10%) was twice as high as that in group Low (0.59 ± 0.14%) (P < 0.05). MECs with the characteristics of native epithelial cells were successfully isolated from the milk and these cells had no obvious RNA degradation or were hardly contaminated with leucocytes or blood red cells. Moreover, the protein expression pattern of cathelicidin 5 in isolated MECs was positive, whereas annexin I (confirmed by real-time polymerase chain reaction), ZW10 interactor and κ-casein were negatively related to the proportion of cis-9, trans-11 CLA in the milk fat.
  
  
  CONCLUSIONS
  The varied individual content of cis-9, trans-11 CLA in cows may be associated with annexin I. These findings may provide some theoretical basis for studies concerning the effects of the individual variation among dairy cows of the synthesis of cis-9, trans-11 CLA. © 2013 Society of Chemical Industry.
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, P.R. China; Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, Jilin Agricultural University, Changchun, 130118, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.forename: Ji-Na
authors.initials: JN
authors.lastname: Lim
authors.forename: Jin-Deok
authors.initials: JD
authors.lastname: Bok
authors.forename: Jeong-Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Sang-Kee
authors.initials: SK
authors.lastname: Kang
authors.forename: Sang-Bum
authors.initials: SB
authors.lastname: Lee
authors.forename: Jin-Hee
authors.initials: JH
authors.lastname: Hwang
authors.forename: Kyung-Hoon
authors.initials: KH
authors.lastname: Lee
authors.forename: Han-Seok
authors.initials: HS
authors.lastname: Kang
authors.forename: Yun-Jaie
authors.initials: YJ
authors.lastname: Choi
authors.forename: Eun-Joong
authors.initials: EJ
authors.lastname: Kim
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Hong-Gu
authors.initials: HG
authors.lastname: Lee
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D017305:Annexin A1 / Q000378:metabolism*; D023181:Antimicrobial Cationic Peptides / Q000378:metabolism; D002364:Caseins / Q000378:metabolism; D002417:Cattle; D004032:Diet; D004041:Dietary Fats / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism*; D005260:Female; D006801:Humans; D007774:Lactation; D044243:Linoleic Acids, Conjugated / Q000378:metabolism*; D008892:Milk / Q000166:cytology / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D054804:Cathelicidins
chemical_list: D017305:Annexin A1; D023181:Antimicrobial Cationic Peptides; D002364:Caseins; D004041:Dietary Fats; D044243:Linoleic Acids, Conjugated; D020543:Proteome; D012333:RNA, Messenger; D054804:Cathelicidins
keywords: cis-9, trans-11 CLA; isolated milk epithelial cells; protein expression profiles; proteomic analysis