The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Sodium channel beta1 subunit-mediated modulation of Nav1.2 currents and cell surface density is dependent on interactions with contactin and ankyrin.

Voltage-gated sodium channels are composed of a pore-forming alpha subunit and at least one auxiliary beta subunit. Both beta1 and beta2 are cell adhesion molecules that interact homophilically, resulting in ankyrin recruitment. In contrast, beta1, but not beta2, interacts heterophilically with contactin, resulting in increased levels of cell surface sodium channels. We took advantage of these results to investigate the molecular basis of beta1-mediated enhancement of sodium channel cell surface density, including elucidating structure-function relationships for beta1 association with contactin, ankyrin, and Nav1.2. beta1/beta2 subunit chimeras were used to assign putative sites of contactin interaction to two regions of the beta1 Ig loop. Recent studies have shown that glutathione S-transferase fusion proteins containing portions of Nav1.2 intracellular domains interact directly with ankyrinG. We show that native Nav1.2 associates with ankyrinG in cells in the absence of beta subunits and that this interaction is enhanced in the presence of beta1 but not beta1Y181E, a mutant that does not interact with ankyrinG. beta1Y181E does not modulate Nav1.2 channel function despite efficient association with Nav1.2 and contactin. beta1Y181E increases Nav1.2 cell surface expression, but not as efficiently as wild type beta1. beta1/beta2 chimeras exchanging various regions of the beta1 Ig loop were all ineffective in increasing Nav1.2 cell surface density. Our results demonstrate that full-length beta1 is required for channel modulation and enhancement of sodium channel cell surface expression.[1]

References

 
WikiGenes - Universities