Ongoing Research: DEG/ENaC RESEARCH

The Degerin/ Epithelial Na+ channel (DEG/ENaC) family includes a large number of cation channels, which are widely expressed from invertebrates to mammals. DEG/ENaC proteins participate in a number of physiological processes ranging from ion homeostasis in epithelia, to mechanosensation and synaptic transmission in neurons.   DEG/ENaC channels are comprised of homo- and hetero-multimeric complexes of related subunits.   Subunits share similar sequence and predicted topology consisting of two transmembrane domains, a large cysteine-rich extracellular domain and intracellular amino and carboxy termini.   Most DEG/ENaC channels are blocked by the diuretic amiloride.

The Acid Sensing Ion Channels (ASICs) are a subclass of the DEG/ENaC family, which are expressed in neurons and activated by a decrease in extracellular pH.    Knockout mouse studies suggest in sensory neurons, ASICs may contribute to mechanosensation and nociception. In brain, ASICs may also modulate synaptic transmission.   Ongoing research is aimed at determining the molecular role of ASICs in these processes.

A large number of DEG/ENaC channels are also expressed in the fruit fly, Drosophila melanogaster.   Although the function of most of these proteins is not known, some have been implicated in salt taste, mechanosensation and thermosensation.   Because of the power of fly genetics, this is an ideal model system to explore the biology of DEG/ENaC proteins.

To read about individual's studies please see: Vivian Costa, Margaret Price, Xiangming Zha, John Wemmie.