- M4 segment in iGluR function
AMPA and NMDA receptors are ionotropic glutamate receptors that make fundamental contributions to synaptic activity in the brain in different ways. Amin et al. show that their respective M4 segments, located on the periphery of their pore domains, contribute to their functional diversity.
- Sex- and vessel-specific AKAP150–TRPV4 organization
Vascular smooth muscle tone can be regulated by angiotensin II, which enhances TRPV4 channel activity via AKAP150-bound protein kinase C. Tajada et al. show that the effect of AKAP150 on TRPV4 channels is inversely proportional to the distance between them, which varies with sex and arterial bed.
- Osmotic fitness in Pseudomonas aeruginosa
Pseudomonas aeruginosa is resistant to drastic osmotic changes because of its ability to quickly jettison small osmolytes through osmotic release channels. Çetiner et al. reveal that it uses one MscL-like and at least two types of MscS-like channels during its osmotic response.
- Isoflurane modulates NaChBac gating
The pharmacological effects of inhaled anesthetics on ion channel function are poorly understood. Sand et al. analyze macroscopic gating of the prokaryotic voltage-gated sodium channel, NaChBac, using a six-state kinetic scheme and demonstrate that isoflurane modulates microscopic gating properties.
- Identifiability, reducibility, and adaptability
Bohner and Venkataraman propose a link between the sensitivity of allosteric macromolecules to their underlying biophysical parameters, the interrelationships between these parameters, and macromolecular adaptability. They argue that “emergent” combinations of parameters yield mechanistic insight that individual parameters cannot.
- Mechanism of Kir channel inactivation
The pore-forming unit of ATP-sensitive K channels is composed of four Kir6.2 subunits. Borschel et al. show that salt bridges between the cytoplasmic domain of adjacent Kir6.2 subunits determine the degree to which channels inactivate after removal of ATP.