Cofilin 1 is a member of the cofilin family of proteins that is expressed in non-muscle CELLS. It has ACTIN depolymerization activity that is dependent on HYDROGEN-ION CONCENTRATION.

A family of low MOLECULAR WEIGHT actin-binding proteins found throughout eukaryotes. They remodel the actin CYTOSKELETON by severing ACTIN FILAMENTS and increasing the rate of monomer dissociation.

A member of the cofilin family of proteins that is expressed in MUSCLE CELLS. It has ACTIN depolymerization activity that is dependent on HYDROGEN-ION CONCENTRATION.

Serine protein kinases involved in the regulation of ACTIN polymerization and MICROTUBULE disassembly. Their activity is regulated by phosphorylation of a threonine residue within the activation loop by intracellular signaling kinases such as P21-ACTIVATED KINASES and by RHO KINASE.

A member of the actin depolymerizing factors. Its depolymerizing activity is independent of HYDROGEN-ION CONCENTRATION.

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.

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.

Fibers composed of MICROFILAMENT PROTEINS, which are predominately ACTIN. They are the smallest of the cytoskeletal filaments.

A dynamic actin-rich extension of the surface of an animal cell used for locomotion or prehension of food.

The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.

A family of low molecular weight proteins that bind ACTIN and control actin polymerization. They are found in eukaryotes and are ubiquitously expressed.

A 90-kDa protein produced by macrophages that severs ACTIN filaments and forms a cap on the newly exposed filament end. Gelsolin is activated by CALCIUM ions and participates in the assembly and disassembly of actin, thereby increasing the motility of some CELLS.

A family of serine-threonine kinases that bind to and are activated by MONOMERIC GTP-BINDING PROTEINS such as RAC GTP-BINDING PROTEINS and CDC42 GTP-BINDING PROTEIN. They are intracellular signaling kinases that play a role the regulation of cytoskeletal organization.

Specialized structures of the cell that extend the cell membrane and project out from the cell surface.

A complex of seven proteins including ARP2 PROTEIN and ARP3 PROTEIN that plays an essential role in maintenance and assembly of the CYTOSKELETON. Arp2-3 complex binds WASP PROTEIN and existing ACTIN FILAMENTS, and it nucleates the formation of new branch point filaments.

Very toxic polypeptide isolated mainly from AMANITA phalloides (Agaricaceae) or death cup; causes fatal liver, kidney and CNS damage in mushroom poisoning; used in the study of liver damage.

The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.

1,N-6-Ethenoadenosine triphosphate. A fluorescent analog of adenosine triphosphate.

A group of intracellular-signaling serine threonine kinases that bind to RHO GTP-BINDING PROTEINS. They were originally found to mediate the effects of rhoA GTP-BINDING PROTEIN on the formation of STRESS FIBERS and FOCAL ADHESIONS. Rho-associated kinases have specificity for a variety of substrates including MYOSIN-LIGHT-CHAIN PHOSPHATASE and LIM KINASES.

A component of the Arp2-3 complex that is related in sequence and structure to ACTIN and that binds ATP. It is expressed at higher levels than ARP2 PROTEIN and does not contain a PROFILIN binding domain.

The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.

Reduced (protonated) form of THIAZOLES. They can be oxidized to THIAZOLIDINEDIONES.

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.

A PROFILIN binding domain protein that is part of the Arp2-3 complex. It is related in sequence and structure to ACTIN and binds ATP.

A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)

'Nerve tissue proteins' are specialized proteins found within the nervous system's biological tissue, including neurofilaments, neuronal cytoskeletal proteins, and neural cell adhesion molecules, which facilitate structural support, intracellular communication, and synaptic connectivity essential for proper neurological function.

Chemical reaction in which monomeric components are combined to form POLYMERS (e.g., POLYMETHYLMETHACRYLATE).

An actin capping protein that binds to the barbed-ends of ACTIN filaments. It is a heterodimer consisting of an alpha and a beta subunit. It regulates actin assembly by stabilizing actin oligomers for elongation. In SKELETAL MUSCLE, CapZ is localized to the Z-disk.

A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.

A large family of MONOMERIC GTP-BINDING PROTEINS that are involved in regulation of actin organization, gene expression and cell cycle progression. This enzyme was formerly listed as EC 3.6.1.47.

Spiny processes on DENDRITES, each of which receives excitatory input from one nerve ending (NERVE ENDINGS). They are commonly found on PURKINJE CELLS and PYRAMIDAL CELLS.

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.

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.

Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.

Major constituent of the cytoskeleton found in the cytoplasm of eukaryotic cells. They form a flexible framework for the cell, provide attachment points for organelles and formed bodies, and make communication between parts of the cell possible.

Actin capping proteins are cytoskeletal proteins that bind to the ends of ACTIN FILAMENTS to regulate actin polymerization.

A class of saturated compounds consisting of two rings only, having two or more atoms in common, containing at least one hetero atom, and that take the name of an open chain hydrocarbon containing the same total number of atoms. (From Riguady et al., Nomenclature of Organic Chemistry, 1979, p31)

A group of hydrolases which catalyze the hydrolysis of monophosphoric esters with the production of one mole of orthophosphate. EC 3.1.3.

Bundles of actin filaments (ACTIN CYTOSKELETON) and myosin-II that span across the cell attaching to the cell membrane at FOCAL ADHESIONS and to the network of INTERMEDIATE FILAMENTS that surrounds the nucleus.

A phosphoinositide present in all eukaryotic cells, particularly in the plasma membrane. It is the major substrate for receptor-stimulated phosphoinositidase C, with the consequent formation of inositol 1,4,5-triphosphate and diacylglycerol, and probably also for receptor-stimulated inositol phospholipid 3-kinase. (Kendrew, The Encyclopedia of Molecular Biology, 1994)

A large family of signal-transducing adaptor proteins present in wide variety of eukaryotes. They are PHOSPHOSERINE and PHOSPHOTHREONINE binding proteins involved in important cellular processes including SIGNAL TRANSDUCTION; CELL CYCLE control; APOPTOSIS; and cellular stress responses. 14-3-3 proteins function by interacting with other signal-transducing proteins and effecting changes in their enzymatic activity and subcellular localization. The name 14-3-3 derives from numerical designations used in the original fractionation patterns of the proteins.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

A method for determining points of contact between interacting proteins or binding sites of proteins to nucleic acids. Protein footprinting utilizes a protein cutting reagent or protease. Protein cleavage is inhibited where the proteins, or nucleic acids and protein, contact each other. After completion of the cutting reaction, the remaining peptide fragments are analyzed by electrophoresis.

A factor identified in the brain that influences the growth and differentiation of NEURONS and NEUROGLIA. Glia maturation factor beta is the 17-kDa polypeptide product of the GMFB gene and is the principal component of GLIA MATURATION FACTOR.

The parts of a macromolecule that directly participate in its specific combination with another molecule.

Bulbous enlargement of the growing tip of nerve axons and dendrites. They are crucial to neuronal development because of their pathfinding ability and their role in synaptogenesis.

The quality of surface form or outline of ORGANELLES.

The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.

Structures which are part of the CELL MEMBRANE or have cell membrane as a major part of their structure.

Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)