Protein structureProtein structure is the three-dimensional arrangement of atoms in an amino acid-chain molecule. Proteins are polymers - specifically polypeptides - formed from sequences of amino acids, which are the monomers of the polymer. A single amino acid monomer may also be called a residue, which indicates a repeating unit of a polymer. Proteins form by amino acids undergoing condensation reactions, in which the amino acids lose one water molecule per reaction in order to attach to one another with a peptide bond.
Protein quaternary structureProtein quaternary structure is the fourth (and highest) classification level of protein structure. Protein quaternary structure refers to the structure of proteins which are themselves composed of two or more smaller protein chains (also referred to as subunits). Protein quaternary structure describes the number and arrangement of multiple folded protein subunits in a multi-subunit complex. It includes organizations from simple dimers to large homooligomers and complexes with defined or variable numbers of subunits.
NeuroinflammationNeuroinflammation is inflammation of the nervous tissue. It may be initiated in response to a variety of cues, including infection, traumatic brain injury, toxic metabolites, or autoimmunity. In the central nervous system (CNS), including the brain and spinal cord, microglia are the resident innate immune cells that are activated in response to these cues. The CNS is typically an immunologically privileged site because peripheral immune cells are generally blocked by the blood–brain barrier (BBB), a specialized structure composed of astrocytes and endothelial cells.
Treaty on the Non-Proliferation of Nuclear WeaponsThe Treaty on the Non-Proliferation of Nuclear Weapons, commonly known as the Non-Proliferation Treaty or NPT, is an international treaty whose objective is to prevent the spread of nuclear weapons and weapons technology, to promote cooperation in the peaceful uses of nuclear energy, and to further the goal of achieving nuclear disarmament and general and complete disarmament. Between 1965 and 1968, the treaty was negotiated by the Eighteen Nation Committee on Disarmament, a United Nations-sponsored organization based in Geneva, Switzerland.
ConnexonIn biology, a connexon, also known as a connexin hemichannel, is an assembly of six proteins called connexins that form the pore for a gap junction between the cytoplasm of two adjacent cells. This channel allows for bidirectional flow of ions and signaling molecules. The connexon is the hemichannel supplied by a cell on one side of the junction; two connexons from opposing cells normally come together to form the complete intercellular gap junction channel.