title: A proteomic study reveals the diversified distribution of plasma membrane-associated proteins in rat hepatocytes.
abstract: To investigate the heterogeneous protein composition of highly polarized hepatocyte plasma membrane (PM), three PM-associated subfractions were obtained from freshly isolated rat hepatocytes using density gradient centrifugation. The origins of the three subfractions were determined by morphological analysis and western blotting. The proteins were subjected to either one-dimensional (1-D) SDS-PAGE or two-dimensional (2-D) benzyldimethyl-n-hexadecylammonium chloride (BAC)/SDS-PAGE before nano-Liquid Chromatography-Electrospray Ionization--tandem mass spectrometry analysis (LC-ESI-MS/MS). A total of 613 non-redundant proteins were identified, among which 371 (60.5%) proteins were classified as PM or membrane-associated proteins according to GO annotations and the literatures and 32.4% had transmembrane domains. PM proteins from microsomal portion possessed the highest percentage of transmembrane domain, about 46.5% of them containing at least one transmembrane domain. In addition to proteins known to be located at polarized liver PM regions, such as asialoglycoprotein receptor 2, desmoplakin and bile salt export pump, several proteins which had the potential to become novel subfraction-specific proteins were also identified, such as annexin a6, pannexin and radixin. Our analysis also evaluated the application of 1-D SDS-PAGE and 2-D 16-BAC/SDS-PAGE on the separation of integral membrane proteins.
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Education Committee, College of Life Sciences, Hunan Normal University, Changsha 410081, P.R. China.
authors.forename: Xuanwen
authors.initials: X
authors.lastname: Li
authors.forename: Jia
authors.initials: J
authors.lastname: Cao
authors.forename: Qihui
authors.initials: Q
authors.lastname: Jin
authors.forename: Chunliang
authors.initials: C
authors.lastname: Xie
authors.forename: Quanyuan
authors.initials: Q
authors.lastname: He
authors.forename: Rui
authors.initials: R
authors.lastname: Cao
authors.forename: Jixian
authors.initials: J
authors.lastname: Xiong
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.forename: Xianchun
authors.initials: X
authors.lastname: Wang
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
mesh_terms: D000818:Animals; D002254:Carbonates / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism*; D002853:Chromatography, Liquid / Q000379:methods; D019295:Computational Biology / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel; D022781:Hepatocytes / Q000166:cytology* / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods; D008565:Membrane Proteins / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D040901:Proteomics / Q000379:methods*; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D002254:Carbonates; D008565:Membrane Proteins; C005686:sodium carbonate