title: Bovine prolactin elevates hTF expression directed by a tissue-specific goat β-casein promoter through prolactin receptor-mediated STAT5a activation.
abstract: Prolactin promotes the expression of exogenous human transferrin gene in the milk of transgenic mice. To elucidate this, a recombinant plasmid of bovine prolactin plus human transferrin vector was co-transfected into cultured murine mammary gland epithelial cells. Prolactin-receptor antagonist and shRNA corresponding to prolactin-receptor mRNA were added into the cell culture mixture to investigate the relations between prolactin-receptor and human transferrin expression after bovine prolactin inducement. Levels of human transferrin in the supernatants were increased under the presentation of bovine prolactin (from 1,076 ± 115 to 1,886 ± 114 pg/ml). With the treatment of prolactin-receptor antagonist or shRNA, human transferrin in cells was declined (1,886 ± 113 vs. 1,233 ± 85 pg/ml or 1,114 ± 75 pg/ml, respectively). An inverse correlation was found between the dosage of prolactin-receptor antagonist and expression level of human transferrin. Real-time qRT-PCR analysis showed that the relative level of signal transducer and activator of transcription 5a (STAT5a) transcript in transfected cells correlated with expression levels of human transferrin in the supernatant of the same cells. Bovine prolactin thus improved the expression of human transferrin through such a possible mechanism that bovine prolactin activated STAT5a transcription expression via combined with prolactin-receptor and suggest a potential utility of the bovine prolactin for efficient expression of valuable pharmaceutical proteins in mammary glands of transgenic animals.
authors: Shanghai Institute of Medical Genetics, Children's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors: Shizhong
authors: S
authors: Jiang
authors: Zhaorui
authors: Z
authors: Ren
authors: Fei
authors: F
authors: Xie
authors: Jingbin
authors: J
authors: Yan
authors: Shuzhen
authors: S
authors: Huang
authors: Yitao
authors: Y
authors: Zeng
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002364:Caseins / Q000235:genetics*; D002417:Cattle; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D006041:Goats; D006801:Humans; D051379:Mice; D011388:Prolactin / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D011981:Receptors, Prolactin / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D050799:STAT5 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014168:Transferrin / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism
chemical_list: D002364:Caseins; D012333:RNA, Messenger; D011981:Receptors, Prolactin; D011994:Recombinant Proteins; D050799:STAT5 Transcription Factor; D014168:Transferrin; D011388:Prolactin