Wag-the-dog Mechanism of Gating in Glutamate Transporters

The Molecular Mechanism of Ion-Dependent Gating in Secondary Transporters

LeuT-like fold Na-dependent secondary active transporters form a large family of integral membrane proteins that transport various substrates against their concentration gradient across lipid membranes, using the free energy stored in the downhill concentration gradient of sodium ions. These transporters play an active role in synaptic transmission, the delivery of key nutrients, and the mainte...

On Simulacra in Wag the Dog

Mechanism-Based Mathematical Model for Gating of Ionotropic Glutamate Receptors.

We present a mathematical model for ionotropic glutamate receptors (iGluR's) that is built on mechanistic understanding and yields a number of thermodynamic and kinetic properties of channel gating. iGluR's are ligand-gated ion channels responsible for the vast majority of fast excitatory neurotransmission in the central nervous system. The effects of agonist-induced closure of the ligand-bindi...

Myosin structure: Does the tail wag the dog?

Previous crystal structures of the myosin head have shown two different conformations, postulated to be the beginning and the end of the actomyosin power stroke. A new crystal structure reveals a dramatically different conformation; but how does this conformation fit into the force-generating cycle of actomyosin interactions?

Glutamate transporters in bone.

In the central nervous system Na(+)-dependent glutamate transporters bind extracellular glutamate and transport it into cells surrounding the synapse, terminating excitatory signals. These glutamate transporters also function as ion channels. The glutamate transporter, GLAST-1, is expressed in the plasma membrane of osteoblasts and osteocytes and is the same molecular weight as in brain. Thus i...