Families
Members of the epithelial Na+ channel (ENaC) family fall into four subfamilies, termed alpha, beta, gamma and delta. The proteins exhibit the same apparent topology, each with two transmembrane (TM) spanning segments, separated by a large extracellular loop. In most ENaC proteins studied to date, the extracellular domains are highly conserved and contain numerous cysteine residues, with flanking C-terminal amphipathic TM regions, postulated to contribute to the formation of the hydrophilic pores of the oligomeric channel protein complexes. It is thought that the well-conserved extracellular domains serve as receptors to control the activities of the channels.
Vertebrate ENaC proteins are similar to degenerins of Caenorhabditis elegans: deg-1, del-1, mec-4, mec-10 and unc-8. These proteins can be mutated to cause neuronal degradation, and are also thought to form sodium channels.
Read more about this topic: Epithelial Sodium Channel
Famous quotes containing the word families:
“Notwithstanding the unaccountable apathy with which of late years the Indians have been sometimes abandoned to their enemies, it is not to be doubted that it is the good pleasure and the understanding of all humane persons in the Republic, of the men and the matrons sitting in the thriving independent families all over the land, that they shall be duly cared for; that they shall taste justice and love from all to whom we have delegated the office of dealing with them.”
—Ralph Waldo Emerson (1803–1882)
“Take two kids in competition for their parents’ love and attention. Add to that the envy that one child feels for the accomplishments of the other; the resentment that each child feels for the privileges of the other; the personal frustrations that they don’t dare let out on anyone else but a brother or sister, and it’s not hard to understand why in families across the land, the sibling relationship contains enough emotional dynamite to set off rounds of daily explosions.”
—Adele Faber (20th century)
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—New York State Division of Youth Newsletter (20th century)