Plant K 1 uptake channel types differ with respect to their voltage, Ca 2 1 , and pH dependence. Here, we constructed recombinant chimeric channels between KST1, a member of the inward-rectifying, acid-activated KAT1 family, and AKT3, a member of the weakly voltage-dependent, proton-blocked AKT2/3 family. The homologous pore regions of AKT3 (amino acids 216 to 287) and KST1 (amino acids 217 to ...

A three-dimensional model of the transmembrane domain of a neuronal-type nicotinic acetylcholine receptor (nAChR), (alpha4)2(beta2)3, was constructed from a homology structure of the muscle-type nAChR recently determined by cryo-electron microscopy. The neuronal channel model was embedded in a fully hydrated DMPC lipid bilayer, and molecular-dynamics simulations were performed for 5 ns. A compa...

Connexin 37 (Cx37) suppresses cell proliferation when expressed in rat insulinoma (Rin) cells, an effect also manifest in vivo during vascular development and in response to tissue injury. Mutant forms of Cx37 with nonfunctional channels but normally localized, wild-type carboxy termini are not growth suppressive. Here we determined whether the carboxy-terminal (CT) domain is required for Cx37-...

in the present study, the effect of porosity on the cathode microstructure (50:50 wt. % lsm: ysz) of a solid oxide fuel cell (sofc) has been examined. a 3-d finite element method for mixed ionic and electronic conducting cathodes (miec) is presented to study the effects of porosity on cell performance. each microstructure was realized using the monte carlo approach with the isotropic type of gr...

The mammalian nuclear pore complex (NPC) is an approximately 120-MDa proteinaceous assembly consisting of approximately 30 proteins and is the sole gate in the nuclear envelope. The human protooncogene Nup214 was first identified as a target for chromosomal translocation involved in leukemogenesis. Nup214 is located on the cytoplasmic face of the NPC and is implicated in anchoring the cytoplasm...

Voltage-gated sodium channels mediate the initiation and propagation of action potentials in excitable cells. Transmembrane segment S4 of voltage-gated sodium channels resides in a gating pore where it senses the membrane potential and controls channel gating. Substitution of individual S4 arginine gating charges (R1-R3) with smaller amino acids allows ionic currents to flow through the mutant ...

A particular type of mesopore extrudates gamma alumina was prepared; which is used as the catalyst in the heavy oil desulfurization unit. Extrudates gamma-alumina support has been made of the boehmite powder from Nephlinsinite mine ores (Surface Area (S.A.) >200 m2/g, Pore Volume (P.V.) =0.48 cm3/g, Average Pore Diameter (A.P.D.) = 8.10 nm); then, many samples of extru...

Advances in imaging and reductionist approaches have provided a high-resolution understanding of nuclear pore complex structure and transport, revealing unexpected mechanistic complexities based on nucleoporin functions and specialized import and export pathways.

Recent investigations into micro-architecture of scaffolds has revealed that mean pore sizes are cell-type specific and influence cellular shape, differentiation, and extracellular matrix secretion. In this context, the overall goal of this study was to investigate whether scaffold mean pore sizes affect mesenchymal stem cell initial attachment, chondrogenic gene expression, and cartilage-like ...

In potassium channels, functional coupling of the inner and outer pore gates may result from energetic interactions between residues and conformational rearrangements that occur along a structural path between them. Here, we show that conservative mutations of a residue near the inner activation gate of the Shaker potassium channel (I470) modify the rate of C-type inactivation at the outer pore...