[PDF] Top 20 (De)constructing the Ryanodine Receptor: Modeling Ion Permeation and Selectivity of the Calcium Release Channel

... Biological ion channels are proteins that passively conduct ions across membranes that are otherwise impermeable to ...of ion permeation and selectivity through a single, open ryanodine ... See full document

... Introduction Ryanodine receptors (RyRs) are Ca ++ channels that control cellular functions by releasing Ca ++ from the sarco/endoplasmic ...- channel pore region of ... See full document

... concentration is increased. In this AMFE, current is reduced by 70% CHECK THIS which is significant, but not as dramatic as the 93% reduction found in the L-type calcium channel (21). The ... See full document

... the permeation pathway with the terminal carboxyl (COO - ) group on a flexible tether than can span a hemisphere of radius 5 Å for aspartates and 7 Å for glutamates ... See full document

... (PNP). Selectivity occurs when the ions interact with the five amino acids described in the main text (Asp-4899, Glu-4900, Asp- 4938, Asp-4945, and ...of ion permeation and selectivity in ... See full document

... an ion into a location. In this model of RyR, there is no explicit ion dehydration energy; all the experimental data—including the high conductance of Mg 2+ through RyR—is reproduced with water being an ... See full document

... L-type calcium channel ...the ion diffusion coefficients of the 7 ion species in the ...of ion selectivity without additional ... See full document

... nearby ryanodine receptor (RyR) calcium ...2+ release that regulates muscle contraction. The L-type and RyR calcium channels have very different physiological ...L-type channel ... See full document

... reduced by approximately 50% when Ca 2+ is added. These AMFEs are large, but not as dramatic as the >90% reduction found in the L-type calcium channel (2). The Poisson-Nernst-Planck/Density Functional ... See full document

... 7). Therefore, it is the screening advantage of Ca 2+ that is the dominant electrostatic term. Ionic screening is a reflection of an ion’s ability to coordinate with neighboring ions and thereby lower the system’s ... See full document

... (PNP). Selectivity occurs when the ions interact with the five amino acids described ...of ion permeation and selectivity in ...of ion permeation and ... See full document

... the calcium release channel (CRC) of cardiac sarcoplasmic reticulum (over the range 6 180 mV) in pure and mixed solutions ...each ion species, the average effective charge distribution on the ... See full document

... and permeation characteristics, we predict this may also be true for IP 3 R-mediated Ca 21 release as ...R) selectivity filter could be pathogenic if they alter the autocountercurrent pro- ...on ... See full document

... 兲 Calcium-selective ion channels are known to have carboxylate-rich selectivity filters, a common motif that is primarily responsible for their high Ca 2+ ...Ca channel兲 to millimolar 共the ... See full document

... 2+ channel (VOC) on the ...the ryanodine receptor (RyR1) and release of Ca 2+ from the sarcoplasmic reticulum (SR) ...pore, selectivity filter and voltage ...2+ release can also ... See full document

... Moreover, the kinetics of the activation produced by ivermectin and midecamyin were similar to the kinetic changes produced by rapamycin in FKBP 12- stripped channels with all d[r] ... See full document

... ionic permeation and these will be included in future ...the ion channel as the selectivity ¯lter, which we treat as a 1D lattice (see ...1 ion and the bulk reservoirs contain mixed ... See full document

... It is evidently quite important to settle on the correct value of the prefactor for channel permeation before a high barrier approximation is used. The channel length d is unlikely to be[r] ... See full document

... 4) Traditional barrier models use the wrong numerical value of the prefactor. For CRC the traditional prefactor is numerically too large by a large factor, 2.2 × 10 4 for K + , which produces an overestimate of (a single ... See full document

... a calcium ion stably bound to the EEEE-ring potentially opens the way to the AMFE, since the resident Ca 2+ ion could prevent the permeation of Na + ...that calcium can significantly ... See full document