Neuropathic pain is experienced worldwide by patients suffering from nerve injuries, infectious or metabolic diseases chemotherapy. However, the treatment options are still limited because of low efficacy and sometimes severe side effects. Recently, deficiency FKBP51 was shown to relieve chronic pain, revealing as a potential therapeutic target. specific potent inhibitor not available until recently which hampered targeting FKBP51.In this study, we used well-established robust spared injury...

Abstract Coronavirus disease (COVID-19) is a contagious respiratory caused by the SARS-CoV-2 virus. The clinical phenotypes are variable, ranging from spontaneous recovery to serious illness and death. On March 2020, global COVID-19 pandemic was declared World Health Organization (WHO). As of February 2023, almost 670 million cases 6,8 deaths have been confirmed worldwide. Coronaviruses, including SARS-CoV-2, contain single-stranded RNA genome enclosed in viral capsid consisting four...

Plants acquire potassium (K+) ions for cell growth and movement via regulated diffusion through K+ channels. Here, we present crystallographic functional data showing that the inward rectifier KAT1 (K+ Arabidopsis thaliana 1) channel is by 14-3-3 proteins further modulated phytotoxin fusicoccin, in analogy to H+-ATPase. We identified a mode III binding site at very C terminus of cocrystallized it with tobacco (Nicotiana tabacum) describe protein complex atomic detail. Validation this...

Recent studies have shown that membrane proteins can be efficiently synthesized in vitro before spontaneously inserting into soluble nanoscale lipid bilayers called nanodiscs (NDs). In this paper, we present experimental details allow a combination of translation ion channels commercially available NDs followed by their direct reconstitution from these nanobilayers standard bilayer setups for electrophysiological characterization. We data showing two model K+ channels, Kcv and KcsA, as well...

We investigate to what extent yeast complementation assays, which in principle can provide large amounts of training data for machine learning models, yield quantitative correlations between growth rescue and single channel recordings. If this were the case, results could be used as surrogate learning-based design. Therefore, we mutated position L94 at cavity entry model K+ KcvPBCV1 all proteinogenic amino acids. The function WT its mutants was investigated by reconstituting them planar...

Many potassium channels show voltage-dependent gating without a dedicated voltage sensor domain. This is not fully understood yet, but often explained by voltage-induced changes of ion occupation in the five distinct K+ binding sites selectivity filter. To better understand this mechanism filter we measured single-channel current and rate constant sub-millisecond channel closure viral KcvNTS for wide range voltages symmetric asymmetric concentrations planar lipid membranes. A model-based...

Hyperpolarization-activated cyclic-nucleotide gated (HCN) channels are important for timing biological processes like heartbeat and neuronal firing. Their weak cation selectivity is determined by a filter domain with only two binding sites K+ one Na+. The latter acts as blocker, which released in combination dynamic widening of the ions, giving rise to mixed K+/Na+ current. Here, we apply molecular dynamics simulations systematically investigate interactions five alkali metal cations open...

Gating of ion channels is based on structural transitions between open and closed states. To uncover the chemical basis individual gates, we performed a comparative experimental computational analysis two K+ channels, KcvS KcvNTS. These small viral encoded channel proteins, with monomer size only 82 amino acids, resemble pore module all complex in terms structure function. Even though both proteins share about 90% acid sequence identity, they exhibit different probabilities ca. KcvNTS 40%...

Lipid bilayers provide many benefits for ion channel recordings, such as control of membrane composition and transport molecules. However, they suffer from high capacitance limiting the bandwidth impeding analysis fast gating. This can be overcome by fitting deviations open-channel noise baseline extended beta distributions. We demonstrate this step-by-step applying it to example viral K

It has become increasingly apparent that the lipid composition of cell membranes affects function transmembrane proteins such as ion channels. Here, we leverage structural and functional diversity small viral K+ channels to systematically examine impact bilayer on pore module single In vitro–synthesized were reconstituted into phosphatidylcholine bilayers ± cholesterol or anionic phospholipids (aPLs). Single-channel recordings revealed a saturating concentration 30% had only minor...

Due to the redundancy of genetic code most amino acids are encoded by multiple synonymous codons. It has been proposed that a biased frequency codons can affect function proteins modulating distinct steps in transcription, translation and folding. Here, we use two similar prototype K+ channels as model systems examine whether codon choice an impact on protein sorting. By monitoring transient expression GFP-tagged mammalian cells, find one is sorted cell cycle-dependent manner either...

The selectivity filter of K+ channels catalyzes a rapid and highly selective transport while serving as gate. To understand the control this gate, we use pore-only channel KcvNTS in which gating is exclusively determined by activity It has been previously shown that mutation at C-terminus pore-helix (S42T) increases permeability introduces distinct voltage-dependent K+-sensitive closures depolarizing voltages. Here, report latter are not generated intrinsic conformational changes gate but...

Voltage-dependent anion-selective channel (VDAC) is one of the main proteins outer mitochondrial membrane all eukaryotes, where it forms aqueous, voltage-sensitive, and ion-selective channels. Its electrophysiological properties have been thoroughly analyzed with planar lipid bilayer technique. To date, however, available results are based on isolations VDACs from tissue or recombinant produced in bacterial systems. It well known that cytosolic overexpression highly hydrophobic often...

The heart tissue is a potential target of various noxae contributing to the onset cardiovascular diseases. However, underlying pathophysiological mechanisms are largely unknown. Human stem cell-derived models promising, but major concern cell immaturity when estimating risks for adults. In this study, 3D aggregates human embryonic cardiomyocytes were cultivated 300 days and characterized regarding degree maturity, structure, composition. Furthermore, effects ionizing radiation (X-rays, 0.1-2...

Biological ion channels precisely control the flow of ions across membranes in response to a range physical and chemical stimuli. With their ability transporting highly selective manner integrating regulatory cues, they are source inspiration for construction solid-state nanopores as sensors or switches practical applications. Here, we summarize recent advancements understanding mechanisms permeation gating channel proteins with focus on elementary steps transport through pore non-canonical...

Some algal viruses have coding sequences for proteins with structural and functional characteristics of pore modules complex K+ channels. Here we exploit the diversity among these channel orthologs to discover new basic principles structure/function correlates in The analysis three similar channels ≤ 86 amino acids (AA) shows that one (Kmpv1) generates an ohmic conductance HEK293 cells while other two (KmpvSP1, KmpvPL1) exhibit typical features canonical Kir Like channels, rectification...

Most potassium channels have two main gate locations, hosting an inner at the cytosolic entrance and a filter in selectivity filter; function of these gates is many coupled. To obtain exclusive insights into molecular mechanisms that determine opening closing gate, we use combination single-channel recordings gating analysis minimal viral channel KcvNTS. This has no its fast negative voltages can therefore be entirely assigned to gate. We find mutations S42 pore helix severely slow down this...

Abstract When the K + channel‐like protein Kesv from Ectocarpus siliculosus virus 1 is heterologously expressed in mammalian cells, it sorted to mitochondria. This targeting can be redirected endoplasmic reticulum (ER) by altering codon usage distinct regions of gene or inserting a triplet hydrophobic amino acids (AAs) into protein's C‐terminal transmembrane domain (ct‐TMD). Systematic variations flavor inserted AAs and/or its show that positive charge AA alone serves as strong signal for...

Chloroviruses are large, plaque-forming, dsDNA viruses that infect chlorella-like green algae live in a symbiotic relationship with protists. have genomes from 290 to 370 kb, and they encode as many 400 proteins. One interesting feature of chloroviruses is potassium ion (K+) channel protein named Kcv. The Kcv encoded by SAG chlorovirus ATCV-1 one the smallest known functional K+ proteins consisting 82 amino acids. KcvATCV-1 has similarities family two transmembrane domain proteins; it...