Table of Contents
What does a connexin do?
Connexins constitute a large family of trans-membrane proteins that allow intercellular communication and the transfer of ions and small signaling molecules between cells.
What is made of connexin?
Intercellular channels are formed from two oligomeric integral membrane protein assemblies, called connexons, which span two adjacent cells’ plasma membranes and join in a narrow, extracellular “gap.” Connexons are formed from connexins, a highly related multigene family consisting of at least 13 members.
Where is connexin found?
The connexin subunit proteins that make up connexons are synthesized on the membranes of the cells endoplasmic reticulum. These subunits are then oligomerized, or combined with other smaller parts, into connexons in the golgi apparatus. The connexons are then delivered to their proper location on the plasma membrane.
Is connexin a cell adhesion molecule?
In addition to their role in cell adhesion, connexins also mediate intercellular signaling, controlling the formation and permeability of channels, which allows a coordinated cell activity [74].
What are connexin gap junctions?
Gap junctions (Gj) form conduits between adjacent cells that are composed of connexin (Cx) protein subunits and allow direct intercellular communication. To date, the connexin gene family comprises 20 members in the mouse and 21 members in the human genome, 19 of which can be grouped as sequence-orthologous pairs.
Where are connexins located?
Connexins have been found in the nucleus, where they may function as transcription factors, and at the mitochondrial membrane, where they may function in bcl-2 activation and apoptosis.
Where are connexins found?
Are Connexons ion channels?
Connexons or gap junction hemichannels are large, nonselective ion channels that reside in the nonjunctional plasma membrane before their assembly into gap junction channels.
What is connexin gap junction?
In 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.
Are connexons ion channels?
What is a connexin?
“Connexins: a myriad of functions extending beyond assembly of gap junction channels”. Cell Commun Signal. 7: 4. doi: 10.1186/1478-811X-7-4.
What is the function of connexin in oocyte?
Connexins are a family of at least 15 proteins that form intercellular membrane channels of gap junctions and allow diffusional movement of ions, metabolites, and potential signaling molecules. These structural molecules play important roles in bi-directional communication between the oocyte and granulosa cells.
What is connexin 26 made up of?
Connexin-26 dodecamer. A gap junction, composed of twelve identical connexin proteins, six in the membrane of each cell. Each of these six units is a single polypeptide which passes the membrane four times (referred to as four-pass transmembrane proteins).
Why are connexin-encoding genes so important?
For this reason, mutations in connexin-encoding genes can lead to functional and developmental abnormalities. Connexins are commonly named according to their molecular weights, e.g. Cx26 is the connexin protein of 26 kDa.