Cloning and gene structure of rat phosphatidylcholine transfer protein, Pctp.
Phosphatidylcholine transfer protein (PC-TP) is a cytosolic lipid transfer protein that promotes intermembrane transfer of phosphatidylcholines but no other phospholipids. Although its physiological function remains unknown, phosphatidylcholine transfer protein is enriched in liver and evidence from model systems suggests a role in hepatocellular selection and transport of biliary phospholipids. To facilitate in vivo studies, a cDNA encoding rat PC-TP was cloned by library screening and 5'-rapid amplification of cDNA ends. Genomic cloning demonstrated the rat Pctp gene spans 10. 8kb and is comprised of six exons. The putative transcription initiation site was identified 50bp upstream of the translation initiation site. Nucleotide sequence analysis of the 5'-flanking region revealed a CAAT- but no TATA-box. Transient transfection of a series of 5'-deleted Pctp-promoter-firefly luciferase constructs into Reuber H35 rat hepatoma cells, which express Pctp mRNA, and Gunn rat fibroblasts, which do not, suggest that cis-acting elements in a 637bp promoter region contribute to enhanced expression of PC-TP in liver.
Marion Bessin Liver Research Center, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, USA.
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Wu
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Boylan
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Cohen
D000595:Amino Acid Sequence; D000727:Androgen-Binding Protein; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005091:Exons / Q000235:genetics; D005786:Gene Expression Regulation; D007438:Introns / Q000235:genetics; D008099:Liver / Q000378:metabolism; D008969:Molecular Sequence Data; D049294:Phospholipid Transfer Proteins; D011401:Promoter Regions, Genetic / Q000235:genetics; D060789:Prostatein; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D051381:Rats; D020218:Response Elements / Q000235:genetics; D060765:Secretoglobins; D017384:Sequence Deletion; D014162:Transfection; D014598:Uteroglobin; D060788:Mammaglobin B
D000727:Androgen-Binding Protein; D002352:Carrier Proteins; D018076:DNA, Complementary; D049294:Phospholipid Transfer Proteins; D060789:Prostatein; D012333:RNA, Messenger; D060765:Secretoglobins; D014598:Uteroglobin; C511484:Scgb1d2 protein, rat; C511483:Scgb1d4 protein, rat; C556468:Scgb2a1 protein, rat; D060788:Mammaglobin B