We have imaged the central ∼ 1 kpc of the circumnuclear starburst disk in the galaxy NGC253 in the HCN(1→0), HCO(1→0), and CO(1→0) transitions at 60 pc resolution using the Owens Valley Radio ObservatoryMillimeter-Wavelength Array (OVRO). We have also obtained Atacama Pathfinder Experiment (APEX) observations of the HCN(4→3) and the HCO(4→3) lines of the starburst disk. We find that the emissio...

Plant growth promoting rhizobacteria produce chemical compounds with different benefits for the plant. Among them, HCN is recognized as a biocontrol agent, based on its ascribed toxicity against plant pathogens. Based on several past studies questioning the validity of this hypothesis, we have re-addressed the issue by designing a new set of in vitro experiments, to test if HCN-producing rhizob...

Aims. Following the first detection of hydrogen isocyanide (HNC) in Titan’s atmosphere, we have devised a new neutral chemical scheme for hydrogen cyanide (HCN) and HNC in the upper atmosphere of Titan. Methods. Our updated chemical scheme contains 137 compounds (with C, H, O and N elements) and 788 reactions (including 91 photolysis processes). To improve the chemistry of HNC and HCN, a carefu...

We present results from an observing campaign of the molecular content of the coma of comet C/1999 S4 (LINEAR) carried out jointly with the millimeter arrays of the Berkeley-Illinois-Maryland Association (BIMA) and the Owens Valley Radio Observatory (OVRO). Using the BIMA array in autocorrelation (‘‘single-dish’’) mode, we detected weak HCN J 1⁄4 1 0 emission from comet C/1999 S4 (LINEAR) at 14...

We present an imaging survey of the CO(1–0), HCN(1–0), and HCO(1–0) lines in the nearby Seyfert galaxies using the Nobeyama Millimeter Array and RAINBOW Interferometer. Some of the observed Seyfert galaxies including NGC 1068, NGC 1097, NGC 5033, and NGC 5194 exhibit strong HCN(1–0) emission on a few 100 pc scales. The observed HCN(1–0)/CO(1–0) and HCN(1–0)/HCO(1–0) line ratios in the Seyfert n...

Cardiac pacemaking, at rest and during the sympathetic fight-or-flight response, depends on cAMP (3',5'-cyclic adenosine monophosphate) signaling in sinoatrial node myocytes (SAMs). The cardiac "funny current" (If) is among the cAMP-sensitive effectors that drive pacemaking in SAMs. If is produced by hyperpolarization-activated, cyclic nucleotide-sensitive (HCN) channels. Voltage-dependent gati...

BACKGROUND A number of studies have shown that ethanol (EtOH) activates dopamine neurocircuitries and is self-administered into the ventral tegmental area (VTA) of the rat brain. In vitro and in silico studies have showed that hyperpolarization-activated cyclic nucleotide-gated (HCN) ionic channels on VTA dopamine neurons may constitute a molecular target of EtOH; however, there is no in vivo e...

The hyperpolarization-activated cation current (I(h)), mediated by HCN channels, contributes to intrinsic neuronal properties, synaptic integration and network rhythmicity. Recent studies have implicated HCN channels in neuropathological conditions including epilepsy. While native HCN channels have been studied at the macroscopic level, the biophysical characteristics of individual neuronal HCN...

Hydrogen sulfide (H2S), an endogenously produced small molecule, protects animals from various stresses. Recent studies demonstrate that animals exposed to H2S are long lived, resistant to hypoxia, and resistant to ischemia-reperfusion injury. We performed a forward genetic screen to gain insights into the molecular mechanisms Caenorhabditis elegans uses to appropriately respond to H2S. At leas...

BACKGROUND The pacemaker current I(f) contributes to spontaneous diastolic depolarization of cardiac autonomic cells. In heterologous expression, HCN channels exhibit a hyperpolarization-activated inward current similar to I(f). However, the links between HCN genes and native I(f) are largely inferential, and it remains unknown whether I(f) is essential for cardiac pacing. METHODS AND RESULTS...