Similar architectures of native and transformed human alpha(2)-macroglobulin sug

2020-03-30 05:57:35

Native alpha transformed tours microscopy

责任者: Boisset, N;Taveau, JC;Pochon, F;Lamy, J 单位: UNIV TOURS,GRP ANAL STRUCT ANTIGEN,F-37032 TOURS,FRANCE.;CNRS,EP JO117,F-37032 TOURS,FRANCE.;UNIV PARIS 11,INST CURIE BIOL,INSERM,U350,F-91405 ORSAY,FRANCE. 来源出处: JOURNAL OF BIOLOGICAL CHEMISTRY, v 271, OCT 18 1996, p 25762- 25769 摘要: The refined three-dimensional structure of native human alpha(2)-macroglobulin (alpha(2)M) has been determined by cryoelectron microscopy and three-dimensional reconstruction, New features corresponding to sigmoid arches, basal bodies, and apical connections were observed in the molecule, Since similar elements are found in the architecture of transformed alpha(2)M, the 2 volumes were aligned in three dimensions. In their common orientations, they show many similarities except near the openings of the central chamber, In the native conformation, these apertures are fully opened, allowing the proteases to access the central chamber of the molecule, while in the transformed structure, they are partially closed. These structures suggest that alpha(2)M conformational change involves a strong lateral compression and a vertical stretching of the native particle seen in its four-petaled flower view to produce the H view of the transformed form. A model of structural transformation, in which all the parts of the alpha(2)M molecule seem involved in the entrapment of the proteinases is proposed. 关键词: quantum wire; split gate; electron confinement potential; far-infrared spectroscopy; electronic states; magnetotransport; nanostructure spectroscopy; electronic states; magnetotransport; nanostructure; HUMAN ALPHA-2-MACROGLOBULIN; 3-DIMENSIONAL RECONSTRUCTION; ELECTRON-MICROSCOPY; CRYOELECTRON MICROSCOPY; MONOMALEIMIDO NANOGOLD; ELECTRON-MICROSCOPY; CRYOELECTRON MICROSCOPY; MONOMALEIMIDO NANOGOLD; CONFORMATIONAL-CHANGES; SINGLE PARTICLES; HUMAN-PLASMA; TILT SERIES; CONFORMATIONAL-CHANGES; SINGLE PARTICLES; HUMAN-PLASMA; TILT SERIES; METHYLAMINE METHYLAMINE