Biomaterial Database

Self-association of chicken gizzard filamin and heavy merofilamin. 1980

P J Davies, and D Wallach, and M Willingham, and I Pastan, and M S Lewis

Filamin is a high molecular weight (subunit Mr 250 000) actin-binding protein isolated from smooth muscle. The protein forms a gel when mixed with solutions of F-actin. A proteolytic fragment of filamin, heavy merofilamin (subunit Mr 240 000), generated by the action of Ca2+-activated protease binds to actin but does not produce gelation. We have studied the self-association properties of filamin and heavy merofilamin by direct examination in the electron microscope and by equilibrium sedimentation distribution studies in the ultracentrifuge. Filamin self-associates reversibly to form dimers; the free energy of dimerization is approximately 7 kcal/mol. Further association to form tetramer and multimer appears to be irreversible. Warming of filamin solutions accelerates aggregation. Heavy merofilamin does not appear to self-associate but is entirely monomeric. These studies suggest that filamin produces gelation of F-actin by binding to actin and then self-associating to cross-link actin filaments into a gel.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D008840	Microfilament Proteins	Monomeric subunits of primarily globular ACTIN and found in the cytoplasmic matrix of almost all cells. They are often associated with microtubules and may play a role in cytoskeletal function and/or mediate movement of the cell or the organelles within the cell.	Actin Binding Protein,Actin-Binding Protein,Actin-Binding Proteins,Microfilament Protein,Actin Binding Proteins,Binding Protein, Actin,Protein, Actin Binding,Protein, Actin-Binding,Protein, Microfilament,Proteins, Actin-Binding,Proteins, Microfilament
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
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D003285	Contractile Proteins	Proteins which participate in contractile processes. They include MUSCLE PROTEINS as well as those found in other cells and tissues. In the latter, these proteins participate in localized contractile events in the cytoplasm, in motile activity, and in cell aggregation phenomena.	Contractile Protein,Protein, Contractile,Proteins, Contractile
D005782	Gels	Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.
D005895	Gizzard, Avian	The posterior portion of the avian stomach located between the PROVENTRICULUS and INTESTINE. It consists of a thick muscular wall and small stones (gastroliths) that function to mechanically grind SEEDS and other ingested objects.	Gizzard,Ventriculus,Avian Gizzard,Avian Gizzards,Gizzards,Gizzards, Avian