Connexin: Difference between revisions

<scene name='70/701426/Wild_type_connexin/1'>Connexins</scene> are integral transmembranal proteins which consist of α-helical domains in the <scene name='70/701426/Connexin_26_basic_structure/6'>4 transmembrane segments</scene> (TM1-TM4) , The extracellular loop <scene name='70/701426/E1_and_e2/1'>two extracellular loops</scene> (E1 and E2), a cytoplasmic loop, an N-terminal helix (NTH), and a C-terminal segment.<scene name='70/701426/Connexons_secondary_structure/1'>This scene</scene> shows the overall connexon secondary structure. The overall contents of a single unit of a connexin is shown in <scene name='70/701426/Connexin_structure2/1'>this scene</scene>. Each connexin consists of 227 amino acids from the <scene name='70/701426/Connexin_26_basic_structure/3'>N terminus to the C terminus</scene>. <scene name='70/701426/Conxoxn_structure/1'>Six connexins</scene> form a hexamerical assembly, known as <scene name='70/701426/Connexin_26_basic_structure/5'>a connexxon or a hemmichannel</scene> , which delineates <scene name='70/701426/Pore/1'>an aqueous pore</scene> with a minimum diameter of ∼1.2 nm. When two hemichannels from adjacent cells dock and join, leaving a gap of ∼2–3 nm, they may form an intercellular [http://www.uniprot.org/uniprot/P29033 gap junction channel] which spans the two plasma membranes and allows the exchange of cytoplasmic molecules with size up to ∼1 kDa.