The N-terminal 1000 residues of apolipoprotein B associate with microsomal triglyceride transfer protein to create a lipid transfer pocket required for lipoprotein assembly

被引:59
作者
Dashti, N
Gandhi, M
Liu, XF
Lin, XL
Segrest, JP [1 ]
机构
[1] Univ Alabama Birmingham, Med Ctr, Dept Med, Birmingham, AL 35294 USA
[2] Univ Alabama Birmingham, Med Ctr, Atherosclerosis Res Unit, Birmingham, AL 35294 USA
[3] Univ Alabama Birmingham, Med Ctr, Dept Nutr Sci, Birmingham, AL 35294 USA
[4] Univ Alabama Birmingham, Med Ctr, Dept Biochem & Mol Genet, Birmingham, AL 35294 USA
[5] Oklahoma Med Res Fdn, Oklahoma City, OK 73104 USA
关键词
D O I
10.1021/bi011757l
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Apolipoprotein (apo) B, the major protein component of the atherogenic low-density lipoprotein (LDL), has a pentapartite structure, NH2-betaalpha(1)-beta(1)-alpha(2)-beta(2)-alpha(3)-COOH, the beta domains containing multiple amphipathic beta strands and the alpha domains containing multiple amphipathic alpha helixes. We recently reported that the first 1000 residues of human apoB-100 have sequence and amphipathic motif homologies to the lipid-pocket of lamprey lipovitellin (LV) [Segrest, J. P., Jones, M. K., and Dashti, N. (1999) J. Lipid Res. 40, 1401-1416]. The lipid-pocket of LV is a small triangular space lined by three antiparallel amphipathic beta sheets, betaA, betaB, and betaD. The betaA and betaB sheets are joined to-ether by an antiparallel alpha helical bundle, a. domain. We proposed [Segrest, J. P., Jones, M. K., and Dashti, N. (1999) J. Lipid Res. 40, 1401-1416] that formation of a LV-like lipid-pocket is necessary for lipid-transfer to apoB-containing lipoprotein particles and that this pocket is formed by association of the region of the betaalpha(1) domain homologous to the betaA and betaB sheets of LV with a betaD-like amphipathic beta sheet from microsomal triglyceride transfer protein (MTP). To test this hypothesis, we generated four truncated cDNA constructs terminating at or near the juncture of the betaalpha(1) and beta(1) domains: Residues 1-800 (apoB:800), 1-931 (apoB:931), 1-1000 (apoB: 1000), and 1-1200 (apoB:1200). Characterization of particles secreted by stable transformants of the McA-RH7777 cell line demonstrated that (i) ApoB:800, missing the betaB domain, was secreted as a lipid-poor aggregate. (ii) ApoB: 93 1, containing most, but not all, of the betaB domain, was secreted as lipid-poor particles unassociated with MTP. (iii) ApoB:1000, containing the entire betaB domain, was secreted as a relatively lipid-rich particle associated hydrophobically with MTP. (iv) ApoB:1200, containing the betaalpha(1) domain plus 200 residues of the beta(1) domain, was secreted predominantly as a lipid-poor particle but also as a minor relatively lipid-rich, MTP-associated particle. We thus have captured an intermediate in apoB-containing particle assembly, a lipid transfer competent pocket formed by association of the complete betaalpha(1) domain of apoB with MTP.
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收藏
页码:6978 / 6987
页数:10
相关论文
共 40 条
[1]   The structural basis of lipid interactions in lipovitellin, a soluble lipoprotein [J].
Anderson, TA ;
Levitt, DG ;
Banaszak, LJ .
STRUCTURE WITH FOLDING & DESIGN, 1998, 6 (07) :895-909
[2]   Lysine and arginine residues in the N-terminal 18% of apolipoprotein B are critical for its binding to microsomal triglyceride transfer protein [J].
Bakillah, A ;
Jamil, H ;
Hussain, MM .
BIOCHEMISTRY, 1998, 37 (11) :3727-3734
[3]   Binding of microsomal trigrlyceride transfer protein to lipids results in increased affinity for apolipoprotein B - Evidence for stable microsomal MTP-lipid complexes [J].
Bakillah, A ;
Hussain, MM .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2001, 276 (33) :31466-31473
[4]  
BANASZAK L, 1991, ANNU REV BIOPHYS BIO, V20, P221, DOI 10.1146/annurev.biophys.20.1.221
[5]   A common binding site on the microsomal triglyceride transfer protein for apolipoprotein B and protein disulfide isomerase [J].
Bradbury, P ;
Mann, CJ ;
Köchl, S ;
Anderson, TA ;
Chester, SA ;
Hancock, JM ;
Ritchie, PJ ;
Amey, J ;
Harrison, GB ;
Levitt, DG ;
Banaszak, LJ ;
Scott, J ;
Shoulders, CC .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1999, 274 (05) :3159-3164
[6]  
BURNETTE WN, 1981, ANAL BIOCHEM, V112, P195, DOI 10.1016/0003-2697(81)90281-5
[7]   Specificity of lipid incorporation is determined by sequences in the N-terminal 37% of ApoB [J].
Carraway, M ;
Herscovitz, H ;
Zannis, V ;
Small, DM .
BIOCHEMISTRY, 2000, 39 (32) :9737-9745
[8]  
CHUNG BH, 1986, METHOD ENZYMOL, V128, P181
[9]  
DASHTI N, 1992, J BIOL CHEM, V267, P7160
[10]   SECRETION OF APOLIPOPROTEIN B-CONTAINING LIPOPROTEINS FROM HELA-CELLS IS DEPENDENT ON EXPRESSION OF THE MICROSOMAL TRIGLYCERIDE TRANSFER PROTEIN AND IS REGULATED BY LIPID AVAILABILITY [J].
GORDON, DA ;
JAMIL, H ;
SHARP, D ;
MULLANEY, D ;
YAO, ZM ;
GREGG, RE ;
WETTERAU, J .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1994, 91 (16) :7628-7632