In the literature, one finds that the homologous SCN5A channel with that mutation shows a 2-4-fold accelerated recovery from fast inactivation without altering any of the other channel parameters. Does that simply mean the time constant of the inactivation is changed? And is that really the same as in SCN1A? (Dichgans, Lancet. 2005) Are there other known changed parameters in FHM?
Hi,
There are several mutations linked to FHM. FHM1 has been linked to a mutation in P/Q calcium channels. FHM2 has been linked to a mutation in the Na/K pump. More recently three mutations in the SCN1A gene (encoding for Nav1.1) were identified, and seem to have different effects on the channel function. Whereas Dichgans et al 2005 and Valmolkot et al 2007 studied the effect of those mutation in heterologous systems expressing a mutated SCN5A, in Kahlig et al 2008 (PNAS) the authors describe the of the three identified mutations of the biophysical properties of SCN1A.
Thanks, Maximiliano. Meanwhile, we found a way to go from the tail currents measured by these groups to a Hodgkin-Huxley description. I am not 100% satisfied with what we did (see here: http://arxiv.org/abs/1403.6801 ) but it is a start.
- Badges
- Science topic
- Similar topics
- Biological Science
- Genetics