Optimized Tuning of Auditory Inner Hair Cells to Encode Complex Sound through Synergistic Activity of Six Independent K Current Entities.

Auditory inner hair cells (IHCs) convert sound vibrations into receptor potentials that drive synaptic transmission. For the precise encoding of sound qualities, receptor potentials are shaped by K conductances tuning the properties of the IHC membrane. Using patch-clamp and computational modeling, we unravel this membrane specialization showing that IHCs express an exclusive repertoire of six voltage-dependent K conductances mediated by K1.

β-Secretase BACE1 Is Required for Normal Cochlear Function.

Cleavage of amyloid precursor protein (APP) by β-secretase BACE1 initiates the production and accumulation of neurotoxic amyloid-β peptides, which is widely considered an essential pathogenic mechanism in Alzheimer's disease (AD). Here, we report that BACE1 is essential for normal auditory function. Compared with wild-type littermates, BACE1 mice of either sex exhibit significant hearing deficits, as indicated by increased thresholds and reduced amplitudes in auditory brainstem responses (ABRs) and decreased distortion product otoacoustic emissions (DPOAEs).

Histidine at position 462 determines the low quinine sensitivity of ether-à-go-go channel superfamily member K 12.1.

Background And Purpose: The ether-à-go-go (Eag) K superfamily comprises closely related K 10, K 11, and K 12 subunits. K 11.1 (termed hERG in humans) gained much attention, as drug-induced inhibition of these channels is a frequent cause of sudden death in humans.

K12.1 channels are not sensitive to GPCR-triggered activation of phospholipase Cβ.

K12.1 K channels are expressed in several brain areas, but no physiological function could be attributed to these subunits so far. As genetically-modified animal models are not available, identification of native K12.

Inverse Modulation of Neuronal K12.1 and K11.1 Channels by 4-Aminopyridine and NS1643.

The three members of the -like (Elk; K12.1-K12.3) family of voltage-gated K channels are predominantly expressed in neurons, but only little information is available on their physiological relevance.

Direct modulation of TRPM4 and TRPM3 channels by the phospholipase C inhibitor U73122.

Background And Purpose: Signalling through phospholipase C (PLC) controls many cellular processes. Much information on the relevance of this important pathway has been derived from pharmacological inhibition of the enzymatic activity of PLC. We found that the most frequently employed PLC inhibitor, U73122, activates endogenous ionic currents in widely used cell lines.

Electrical Wiring of the Aldehyde Oxidoreductase PaoABC with a Polymer Containing Osmium Redox Centers: Biosensors for Benzaldehyde and GABA.

Biosensors for the detection of benzaldehyde and γ-aminobutyric acid (GABA) are reported using aldehyde oxidoreductase PaoABC from Escherichia coli immobilized in a polymer containing bound low potential osmium redox complexes. The electrically connected enzyme already electrooxidizes benzaldehyde at potentials below -0.15 V (vs.