Biomaterial Database

Biochemical studies of human placental microvillous plasma membrane proteins. 1985

P D Webb, and P W Evans, and C M Molloy, and P M Johnson

Isolated human syncytiotrophoblast microvillous plasma membranes (StMPM) have been examined by electron microscopy, SDS-polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional PAGE (2D-PAGE), and immunoblots. Electron microscopy of StMPM pellets revealed populations of membrane-bounded vesicles that disrupted after treatment with the chaotrope 3M KCl for 16 hr; with increasing molarity of another chaotrope (NH4SCN), the vesicles became smaller and more homogeneous. NH4SCN treatment resulted in significant reduction on SDS and 2D-PAGE analysis of only one protein at 80kd, shown by immunoblotting to be transferrin; 3M KCl had little effect and appeared to be a poor chaotrope. Chromogenic silver staining of SDS-PAGE gels demonstrated over 50 StMPM-associated discrete protein components. Immunoblotting revealed transferrin (80kd), albumin (65kd), IgG heavy chain (56kd), and Gc protein (56kd). Alpha-2-macroglobulin (alpha 2M) was identified at 180kd and 95kd; the smaller component may be a proteolytic derivative indicating alpha 2M binding to a trophoblast surface protease. Numerous discrete protein dots, and groups of dots characteristic of charge heterogeneity of individual proteins, were observed on high resolution 2D-PAGE. The most intensely stained proteins were transferrin (80kd), albumin (65kd), placental-type alkaline phosphatase (66kd), and actin (46kd). This 2D-PAGE technique is a superior method for analyzing the trophoblast membrane proteins, and the system described will enable systematic mapping of these components.

UI	MeSH Term	Description	Entries
D007120	Immunochemistry	Field of chemistry that pertains to immunological phenomena and the study of chemical reactions related to antigen stimulation of tissues. It includes physicochemical interactions between antigens and antibodies.
D008565	Membrane Proteins	Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.	Cell Membrane Protein,Cell Membrane Proteins,Cell Surface Protein,Cell Surface Proteins,Integral Membrane Proteins,Membrane-Associated Protein,Surface Protein,Surface Proteins,Integral Membrane Protein,Membrane Protein,Membrane-Associated Proteins,Membrane Associated Protein,Membrane Associated Proteins,Membrane Protein, Cell,Membrane Protein, Integral,Membrane Proteins, Integral,Protein, Cell Membrane,Protein, Cell Surface,Protein, Integral Membrane,Protein, Membrane,Protein, Membrane-Associated,Protein, Surface,Proteins, Cell Membrane,Proteins, Cell Surface,Proteins, Integral Membrane,Proteins, Membrane,Proteins, Membrane-Associated,Proteins, Surface,Surface Protein, Cell
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D002824	Chorionic Villi	Threadlike vascular projections of the chorion. Chorionic villi may be free or embedded within the DECIDUA forming the site for exchange of substances between fetal and maternal blood (PLACENTA).	Placental Villi,Labyrinth of the Placenta,Labyrinthine Placenta,Placental Labyrinth Layer,Chorionic Villus,Labyrinth Layer, Placental,Placental Labyrinth Layers,Placental Villus,Villi, Chorionic,Villi, Placental,Villus, Chorionic,Villus, Placental
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man