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Title: Structure and Function of Phosphatidylcholine transfer protein (PC-TP)/StarD2

Abstract

Phosphatidylcholine transfer protein (PC-TP) is a highly specific soluble lipid binding protein that transfers phosphatidylcholine between membranes in vitro. PC-TP is a member of the steroidogenic acute regulatory protein-related transfer (START) domain superfamily. Although its biochemical properties and structure are well characterized, the functions of PC-TP in vivo remain incompletely understood. Studies of mice with homozygous disruption of the Pctp gene have largely refuted the hypotheses that this protein participates in the hepatocellular selection and transport of biliary phospholipids, in the production of lung surfactant, in leukotriene biosynthesis and in cellular phosphatidylcholine metabolism. Nevertheless, Pctp-/- mice exhibit interesting defects in lipid homeostasis, the understanding of which should elucidate the biological functions of PC-TP.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
959466
Report Number(s):
BNL-82452-2009-JA
Journal ID: ISSN 0006-3002; BBACAQ; TRN: US201016%%610
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochimica et Biophysica Acta; Journal Volume: 1771; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; BIOLOGICAL FUNCTIONS; BIOSYNTHESIS; DEFECTS; GENES; HOMEOSTASIS; IN VITRO; IN VIVO; LECITHINS; LIPIDS; LUNGS; MEMBRANES; METABOLISM; MICE; PHOSPHOLIPIDS; PRODUCTION; PROTEINS; TRANSPORT; national synchrotron light source

Citation Formats

Kanno,K., Wu, M., Scapa, E., Roderick, S., and Cohen, D. Structure and Function of Phosphatidylcholine transfer protein (PC-TP)/StarD2. United States: N. p., 2007. Web. doi:10.1016/j.bbalip.2007.04.003.
Kanno,K., Wu, M., Scapa, E., Roderick, S., & Cohen, D. Structure and Function of Phosphatidylcholine transfer protein (PC-TP)/StarD2. United States. doi:10.1016/j.bbalip.2007.04.003.
Kanno,K., Wu, M., Scapa, E., Roderick, S., and Cohen, D. Mon . "Structure and Function of Phosphatidylcholine transfer protein (PC-TP)/StarD2". United States. doi:10.1016/j.bbalip.2007.04.003.
@article{osti_959466,
title = {Structure and Function of Phosphatidylcholine transfer protein (PC-TP)/StarD2},
author = {Kanno,K. and Wu, M. and Scapa, E. and Roderick, S. and Cohen, D.},
abstractNote = {Phosphatidylcholine transfer protein (PC-TP) is a highly specific soluble lipid binding protein that transfers phosphatidylcholine between membranes in vitro. PC-TP is a member of the steroidogenic acute regulatory protein-related transfer (START) domain superfamily. Although its biochemical properties and structure are well characterized, the functions of PC-TP in vivo remain incompletely understood. Studies of mice with homozygous disruption of the Pctp gene have largely refuted the hypotheses that this protein participates in the hepatocellular selection and transport of biliary phospholipids, in the production of lung surfactant, in leukotriene biosynthesis and in cellular phosphatidylcholine metabolism. Nevertheless, Pctp-/- mice exhibit interesting defects in lipid homeostasis, the understanding of which should elucidate the biological functions of PC-TP.},
doi = {10.1016/j.bbalip.2007.04.003},
journal = {Biochimica et Biophysica Acta},
number = 6,
volume = 1771,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • No abstract prepared.
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  • Discoidal-reconstructed high density lipoproteins (rHDL) were used to study the effect of HDL substrates on phosphatidylcholine (PC) transfer by human plasma phospholipid transfer protein (PLTP) by changing the composition and size of rHDL. Sonicated egg-PC:cholesterol vesicles containing radiolabeled dipalmitoyl-PC ({sup 14}C-DPPC) were used as donors and varied rHDL, consisting of apolipoprotein, phospholipid and cholesterol, were used as acceptors. PLTP, purified about 3,400-fold, was used in the experiments. Activity was measured by the percent {sup 14}C-DPPC transferred from vesicles into rHDL. There was no selectivity in facilitated {sup 14}C-DPPC transfer at 5:1, of HDL; however, apolipoprotein (apo) AI-containing rHDL was moremore » stable than apo AII and apo C-containing rHDL in the incubation system. Therefore, apo AI was used in subsequent experiments.« less
  • The 1,3-dipolar cyloaddition of phenyl azide to the metal-coordinated isocyanide ligands in Tp{prime}Rh(CNR){sub 2} (Tp{prime} = hydrotris (3,5-dimethylpyrazolyl) borate, R = neopentyl, methyl, 2,6-xylyl; 1a-c) or Cp*Rh(CN-neopentyl){sub 2} (Cp* = {eta}{sup 5}-1,2,3,4,5-pentamethylcyclopentadienyl; 3) in hexane produces the complexes Tp{prime}Rh(CNR)({eta}{sup 2}-PhN{double_bond}C{double_bond}NR) (R = neopentyl, methyl, 2,6-xylyl; 2a-c) and Cp*Rh(CNR)({eta}{sup 2}-PhN{double_bond}C{double_bond}N-neopentyl) (4), respectively, in high yield. The reaction is regiospecific with respect to coordination of the unsymmetrical carbodiimide ligand. Reaction of 2,4-xylyl azide with Tp{prime}Rh(CN-2-tolyl){sub 2} (1d) gives by X-ray diffraction. Complex 2d crystallizes from toluene in the triclinic space group PI with a = 10.962 (6) {Angstrom}, b = 11.238 (4)more » {Angstrom}, c = 8.691 (14) {Angstrom}, {alpha} = 96.95 (5){degrees}, {beta} = 104.02 (5){degrees}, {gamma} = 101.00 (4){degrees}, V = 2159 (5) {Angstrom}{sup 3}, and Z = 2. The structure of 2d confirms the bidentate bonding of the carbodiimide and shows that the nitrogen of the carbodiimide arising from the azide is coordinated to rhodium. Photolysis of 2a in benzene produces Tp{prime}Rh(H)(Ph)(CN-neopentyl) (5) along with free PhN{double_bond}C{double_bond}N-neopentyl with a quantum yields of 1.0 {+-} 0.03, whereas complex 4 is photochemically unreactive in benzene solution. The conversion of 2a to 5 can also be effected thermally, although the rate is slow at 100 {degrees}C. Photolysis of 2a in the solid state results in an intramolecular reaction to give Tp{prime}Rh(H)(2-(N{double_bond}C{double_bond}N-neopentyl)C{sub 6}H{sub 4})(CN-neopentyl) (7). Addition of excess neopentyl isocyanide to 2a gives the azametallacyclobutane complex Tp{prime}RhC({double_bond}N-neopentyl)N(Ph)C({double_bond}N-neopentyl)(CN-neopentyl) (8). 51 refs., 5 figs., 4 tabs.« less
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