title: Quantitative Targeted Absolute Proteomics for 28 Transporters in Brush-Border and Basolateral Membrane Fractions of Rat Kidney.
abstract: The purpose of the present study was to determine the absolute protein expression levels of various transporters in renal brush-border membrane (BBM) and basolateral membrane (BLM) fractions, in order to understand the quantitative differences in average transport activities among different transporters at each cellular membrane. BBM and BLM fractions of rat kidney were prepared and digested with trypsin, and simultaneous absolute quantification of 28 transporters and a BLM marker, Na(+)/K(+)-ATPase, was performed using our established quantitative-targeted absolute proteomics (QTAP) technique. In BBM fraction, the protein expression levels of bcrp, urat1, mate1, octl1, mrp4, mdr1a, and abca3 were 40.3, 22.2, 8.90, 4.85, 4.69, 3.22, and 0.976 fmol/μg protein, respectively. In BLM fraction, the protein expression levels of oat1, oat3, oct1, mrp6, and mrp1 were 10.6, 10.2, 4.59, 0.724, and 0.271 fmol/μg protein, respectively. The expression levels of abca2, abca4, abca5, abca12, abcb4, mrp5, abcc9, abcg1, abcg5, lat1, ntcp, pgt, oatp2b1, oatp1b2, oatp3a1, and oct3 were under the limit of quantification in both fractions. The quantitative transporter protein expression profiles at these membranes, as determined by QTAP analysis, should be helpful to understand the contributions of individual transporters to renal excretion of xenobiotics and endogenous compounds.
authors.affiliation: Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Uchida
authors.affiliation: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Toyohara
authors.affiliation: Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Ohtsuki
authors.affiliation: Department of Membrane Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan; Advanced Science Research Center, Okayama University, Okayama, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Moriyama
authors.affiliation: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan; Department of Clinical Biology and Hormonal Regulation, Tohoku University Graduate School of Medicine, Sendai, Japan; Division of Medical Science, Tohoku University Graduate School of Biomedical Engineering, Sendai, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Abe
authors.affiliation: Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan. Electronic address: terasaki.tetsuya@m.tohoku.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Terasaki
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008871:Microvilli / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D026901:Membrane Transport Proteins
keywords: ABC transporters; HPLC (high-performance/pressure liquid chromatography); drug transport; mass spectrometry; membrane transport; membrane transporter; proteins; proteomics; renal excretion; solute transporters