A two-stranded helical polymer of the protein actin. Actin filaments are a major component of the contractile apparatus of skeletal muscle and the microfilaments of the cytoskeleton of eukaryotic cells. The filaments, comprising polymerized globular actin molecules, appear as flexible structures with a diameter of 5-9 nm. They are organized into a variety of linear bundles, two-dimensional networks, and three dimensional gels. In the cytoskeleton they are most highly concentrated in the cortex of the cell just beneath the plasma membrane.

Combining with inositol-1,4,5-triphosphate to initiate a change in cell activity.

A stable complex of seven subunits, two actin-related proteins, Arp2 and Arp3, and five novel proteins (ARPC1-5). Functions in the nucleation of actin filaments.

The joining of 2 or more lipid bilayer membranes that surround a cell.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

Interacting selectively with 5S ribosomal RNA, the smallest RNA constituent of a ribosome.

Penetrating at least one phospholipid bilayer of a plasma membrane. Also refers to the state of being buried in the bilayer with no exposure outside the bilayer.

purinergic nucleotide receptor activity, G-protein coupled

purinergic nucleotide receptor activity, G protein coupled

The chemical reactions involving heterocyclic compounds, those with a cyclic molecular structure and at least two different atoms in the ring (or rings).

The chemical reactions involving ether lipids, lipids that contain (normally) one fatty alcohol in ether linkage to one of the carbon atoms (normally C-1) of glycerol.

The chemical reactions involving glycerolipids, any lipid with a glycerol backbone. Diacylglycerol and phosphatidate are key lipid intermediates of glycerolipid biosynthesis.

The chemical reactions involving glyoxylate, the anion of glyoxylic acid, HOC-COOH.

The chemical reactions involving phosphatidylinositol, any glycophospholipid with its sn-glycerol 3-phosphate residue is esterified to the 1-hydroxyl group of 1D-myo-inositol.