Biomaterial Database

Phosphatidylinositol 3-kinase binds to profilin through the p85 alpha subunit and regulates cytoskeletal assembly. 1998

V Bhargavi, and V B Chari, and S S Singh

Department of Biochemistry, Osmania University, Hyderabad, India.

Phosphatidylinositol 3-kinase (PI3-K), endowed with catalytic (110kDa) and regulatory (85kDa) subunits co-precipitates with anti-tyrosine antibodies in mitogen-activated cells. Association of PI3-K with cytoskeleton activates its catalytic activity through undeciphered mechanisms. Recently Singh et al., (Biochemistry, 35, 16544-16549, 1996) have shown that profilin activates PI3-K activity in a concentration-dependent manner. Consequently, we investigated the interaction between the PI3-K and profilin employing the GSTp85 alpha fusion protein and the results indicate a specific interaction between profilin and p85 alpha. The effect of p85 alpha/profilin complex on polymerization of actin monomers was monitored fluorimetrically employing pyrene-labelled actin monomers. It was noted that p85 alpha/profilin complex inhibits actin polymerization suggesting that profilin can simultaneously bind to actin as well as to p85 alpha. The affinity of p85 alpha/profilin complex to actin increases in the presence of p85 alpha subunit of PI3-K as compared to profilin itself.

UI	MeSH Term	Description	Entries
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
D011993	Recombinant Fusion Proteins	Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.	Fusion Proteins, Recombinant,Recombinant Chimeric Protein,Recombinant Fusion Protein,Recombinant Hybrid Protein,Chimeric Proteins, Recombinant,Hybrid Proteins, Recombinant,Recombinant Chimeric Proteins,Recombinant Hybrid Proteins,Chimeric Protein, Recombinant,Fusion Protein, Recombinant,Hybrid Protein, Recombinant,Protein, Recombinant Chimeric,Protein, Recombinant Fusion,Protein, Recombinant Hybrid,Proteins, Recombinant Chimeric,Proteins, Recombinant Fusion,Proteins, Recombinant Hybrid
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
D003599	Cytoskeleton	The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.	Cytoplasmic Filaments,Cytoskeletal Filaments,Microtrabecular Lattice,Cytoplasmic Filament,Cytoskeletal Filament,Cytoskeletons,Filament, Cytoplasmic,Filament, Cytoskeletal,Filaments, Cytoplasmic,Filaments, Cytoskeletal,Lattice, Microtrabecular,Lattices, Microtrabecular,Microtrabecular Lattices
D000199	Actins	Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.	F-Actin,G-Actin,Actin,Isoactin,N-Actin,alpha-Actin,alpha-Isoactin,beta-Actin,gamma-Actin,F Actin,G Actin,N Actin,alpha Actin,alpha Isoactin,beta Actin,gamma Actin
D001704	Biopolymers	Polymers synthesized by living organisms. They play a role in the formation of macromolecular structures and are synthesized via the covalent linkage of biological molecules, especially AMINO ACIDS; NUCLEOTIDES; and CARBOHYDRATES.	Bioplastics,Bioplastic,Biopolymer
D015151	Immunoblotting	Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.	Dot Immunoblotting,Electroimmunoblotting,Immunoelectroblotting,Reverse Immunoblotting,Immunoblotting, Dot,Immunoblotting, Reverse,Dot Immunoblottings,Electroimmunoblottings,Immunoblottings,Immunoblottings, Dot,Immunoblottings, Reverse,Immunoelectroblottings,Reverse Immunoblottings
D051304	Profilins	A family of low molecular weight proteins that bind ACTIN and control actin polymerization. They are found in eukaryotes and are ubiquitously expressed.	Profilin,Profilin 1,Profilin 2,Profilin 3,Profilin 4,Profilin I,Profilin Proteins,Profilin-1,Profilin-2,Profilin-3,Profilin-4
D019869	Phosphatidylinositol 3-Kinases	Phosphotransferases that catalyzes the conversion of 1-phosphatidylinositol to 1-phosphatidylinositol 3-phosphate. Many members of this enzyme class are involved in RECEPTOR MEDIATED SIGNAL TRANSDUCTION and regulation of vesicular transport with the cell. Phosphatidylinositol 3-Kinases have been classified both according to their substrate specificity and their mode of action within the cell.	PI-3 Kinase,Phosphatidylinositol-3-OH Kinase,PtdIns 3-Kinase,PI 3-Kinase,PI-3K,PI3 Kinases,PI3-Kinase,Phosphoinositide 3 Kinases,Phosphoinositide 3-Hydroxykinase,PtdIns 3-Kinases,3-Hydroxykinase, Phosphoinositide,Kinase, PI-3,Kinase, Phosphatidylinositol-3-OH,Kinases, PI3,Kinases, Phosphoinositide 3,PI 3 Kinase,PI3 Kinase,Phosphatidylinositol 3 Kinases,Phosphatidylinositol 3 OH Kinase,Phosphoinositide 3 Hydroxykinase,PtdIns 3 Kinase,PtdIns 3 Kinases