Rapid technological change is opening new possibilities for electrification of the transportation sector. This paper offers novel empirical guidance to policymakers considering investments in electric urban buses. We determine environmental benefit using buses rather than diesel or Compressed Natural Gas (CNG) transit. For and CNG we calculate air pollution damages by combining emission rates w...

Cyclic nucleotide-gated (CNG) channels play a central role in the conversion of sensory stimuli into electrical signals. CNG channels form heterooligomeric complexes built of A and B subunits. Here, we study the subunit stoichiometry of the native rod CNG channel by chemical crosslinking. The apparent molecular weight (M(w)) of each crosslink product was determined by SDS-PAGE, and its composit...

Cyclic nucleotide-gated (CNG) ion channels are crucial for phototransduction in rod photoreceptors. Light triggers a biochemical cascade that reduces the concentration of cGMP in rods, closing CNG channels, which leads to membrane potential hyperpolarization and a decrease in the concentration of intracellular Ca2+. During light adaptation, the sensitivity of CNG channels to cGMP is decreased b...

Ion channels activated by the binding of cyclic nucleotides first were discovered in retinal rods where they generate the cell's response to light. In other systems, however, it has been difficult to unambiguously determine whether cyclic nucleotide-dependent processes are mediated by protein kinases, their classical effector enzymes, or cyclic nucleotide-gated (CNG) ion channels. Part of this ...

Transient elevations of intracellular Ca2+ play an important role in regulating the sensitivity of olfactory transduction, but such elevations have not been demonstrated in the olfactory cilia, which are the site of primary odor transduction. To begin to understand Ca2+ signaling in olfactory cilia, we used high-resolution imaging techniques to study the Ca2+ transients that occur in salamander...

Cyclic nucleotide-gated (CNG) channels are critical components of the vertebrate visual transduction cascade involved in converting light-induced changes in intracellular cGMP concentrations into electrical signals that can be interpreted by the brain as visual information. To characterize regulatory mechanisms capable of altering the apparent ligand affinity of cone channels, we have expressed...

Cyclic nucleotide-gated (CNG) and hyperpolarization-activated cyclic nucleotide-regulated (HCN) ion channels play crucial physiological roles in phototransduction, olfaction, and cardiac pace making. These channels are characterized by the presence of a carboxyl-terminal cyclic nucleotide-binding domain (CNBD) that connects to the channel pore via a C-linker domain. Although cyclic nucleotide b...

Activation of photoreceptor and olfactory cyclic nucleotide-gated (CNG) channels involves distinct ligand-binding and channel-gating reactions. To dissociate binding from gating, we identified the first competitive antagonists of CNG channels: specific phosphorothioate derivatives of cAMP and cGMP. We also identified membrane-permeant forms of these molecules that are antagonists and that will ...