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The Taranaki Basin, located offshore New Zealand, is a Cretaceous rift basin that has well defined yet complex Miocene deepwater sedimentary systems. We analyze a pronounced anomalous seismic response in a Late Miocene to Early Pliocene deepwater channel within the 2005 Hector 3D survey located in the southern Taranaki Basin. Several seismic attributes were calculated to interpret the extent of these anomalous features. Analogues within both the Iron River reservoir in Albania, Canada and the East Breaks Basin Four, offshore Gulf of Mexico suggest that these anomalous seismic features are most likely channel-body basal scours. Another interpretation suggests that these scours were formed and later filled by mass transport deposits (MTDs) with sediment ponding as suggested from some studies within the Molasse Basin in southern Germany. Alternatively, these scours could also be interpreted as pockmarks resulting from channel abandonment and fluid escape due to compaction. Others describe this process within submarine canyon systems, offshore Equatorial Guinea. However, there is compelling evidence to suggest that these features are most likely channel-body basal scours rather than being related to MTDs or pockmarks. Within all of the interpretations, there is evidence of differential compaction, which is further supported by the reflectors displaying a slight doming immediately above where the scours are located. Geological feature: Seismic geomorphology anomalies within a Pliocene deepwater channel complex in the Taranaki Basin, offshore New Zealand Seismic appearance: Asymmetric bowl-shaped geometry with high-amplitude reflectors that are incised into underlying sediment Alternative interpretations: Pockmarks resulting from channel abandonment and fluid escape due to compaction Features with similar appearance: Channel scours or pockmarks Formation: Mount Messenger Formation, Taranaki Basin Age: Late Miocene to Early Pliocene Location: Southern Taranaki Basin, New Zealand Available data: Hector 3D data set, Kiwa-1, and Hector-1 wells Analysis tools: 3D seismic data, well logs, and seismic attributes

We have constructed a channel complex model at a scale of 1:10,000 by stacking 3D-printed polylactide layers with negative relief meandering channels. This model was subjected to an ultrasonic common-offset acquisition in a water tank (with the water filling the channels), and the result was treated as a zero-offset 3D acoustic reflection seismogram, receiving a deterministic deconvolution and a poststack migration as data treatment. We then developed an algorithm to yield volumes of estimated two-way time layer thickness from multiple-frequency volumes obtained through the short-time Fourier transform. The estimated thicknesses were compared with the measurements of the physical model obtained through X-ray computed tomography. Despite the strong signal attenuation and imaging issues, the results were rather satisfactory, increasing the confidence in using spectral decomposition for quantitative seismic analysis.

In accordance with the water management zoning of the territory of Ukraine, the Poltva river basin belongs to the Vistula river basin region. The evaluation methodology of the channel and floodplain river complex state was proposed by Himko R. V. (2005). According to this methodology, the parameters (23 indicators), characterizing river state by points scale (5 quality classes), were defined. The research included three steps. During the preparatory stage cartographic materials were investigated and the coastal protection zones were highlighted. The fieldwork stage included: visual assessment of water quality and of the state of channels; identification of sources of pollution and clogging of waters and coastal areas; study of features of anthropogenic load within floodplains. In the third stage, generalization and evaluation works were carried out. Wastewater discharges from enterprises and coastal settlements affect the water quality of the study area. Lviv has the greatest economic impact on the Poltva river due to its channelling within the city and due to large volumes of wastewater discharges (121.4 million m3 in 2017). The water quality of the Poltva River tributaries depends on sewage discharges from small industrial and public utilities, as well as on unauthorized sewage discharges in villages. Significant parts of the river channels are regulated. Drainage systems, that occupy much of the study area, as well as ponds and small reservoirs, directly affect on the hydrological regime of the rivers. The level of land-use of coastal territories is characterized by their urbanization level and their level of plowing. The urbanization of the upper reaches of the Poltva river valley is a determining factor that has influenced the sanitary status of its channel. Outside the Lviv city, many coastal areas (within the coastal protection zones) are plowed. Overgrowing of waters and obstruction of channels by water and coastal plant remains lead to a significant deterioration of sanitary conditions of the rivers, hence to secondary contamination of its waters. Geoecological state of the Poltva river channel and floodplain complex was designated as «unsatisfactory» (4th grade from 5 classes), of Yarychivka and Gologirka river complexes – as «satisfactory» (3rd grade), of other rivers – as «rather good» (2nd grade). The rivers of the Poltva watershed are under significant economic influence. To improve the geoecological state of river channels and floodplains, a complex of water protection measures is required: reduction of insufficiently treated wastewater discharges of Lviv city; cleaning of watercourses; monitoring of compliance with water protection rules etc.

A new application of K-NN was implemented to classify various substances using measured UWB channel complex coefficients. This study provides a low-cost system to detect different substance...

Major reservoirs in Field A namely A-2, A-3U, A-3M, and A-3L, are deposited within a multi stacked channel complex system within Group I in Malay Basin. These reservoirs were previously understood based on existing data to have no or very minimal vertical communication between them and are treated as separate systems. In 2018, three wells were proposed to drain the attic oil in the north region of A-3U reservoir. When drilling these infill wells, it was discovered that the pressure has exceeded initial reservoir pressure although the reservoir has been idle for almost a year prior to the drilling. The results of the multi-rate test of two of the three infill wells that are less than 1 km apart are significantly different from one another. Post drilling, more tests were executed to investigate the connection between the sand. Studies were also done by incorporating the static and dynamic reservoir modeling data. Based on the result of the tests and studies, it was concluded that all of the major sands are connected at some areas. This new finding on the connectivity might be able to explain the additional volume needed to history match some of the reservoirs. Establishing stratigraphy concepts of a reservoir particularly in a channel complex system is an ongoing process, in this case, a brown field of almost 20 years of production. All data including new well data and dynamic data plays a vital role for a better understanding of the reservoir. It is essential to incorporate the updated geological understanding into the static model to have a representative simulation for better history matching and prediction. Moving forward, instead of building a separate grid model for each reservoir, a larger framework consist of intercalated reservoir grids will be built with this new geological understanding for dynamic simulation.

A reversible pseudo-single-ligand-gated ion transportation switch of ON–OFF–ON type was achieved through host–guest complexation with pillar[6]arene (P[6]) as the ion channel, and a photoresponsive azobenzene as the dual-role (open and close) ligand.

Resting membrane potential determines the excitability of the cell and is essential for the cellular electrical activities. The NALCN channel mediates sodium leak currents, which positively adjust resting membrane potential towards depolarization. The NALCN channel is involved in several neurological processes and has been implicated in a spectrum of neurodevelopmental diseases. Here, we report the cryo-EM structure of rat NALCN and mouse FAM155A complex to 2.7 Å resolution. The structure reveals detailed interactions between NALCN and the extracellular cysteine-rich domain of FAM155A. We find that the non-canonical architecture of NALCN selectivity filter dictates its sodium selectivity and calcium block, and that the asymmetric arrangement of two functional voltage sensors confers the modulation by membrane potential. Moreover, mutations associated with human diseases map to the domain-domain interfaces or the pore domain of NALCN, intuitively suggesting their pathological mechanisms., The NALCN channel mediates sodium leak currents, which in turn adjusts resting membrane potential and neuronal excitability. Here the authors describe a cryo-EM structure of mammalian NALCN-FAM155A channel complex, showing how selectivity filter contributes to sodium permeation and calcium block and how the voltage sensors contribute to current modulation.

The voltage-gated potassium channel Kv1.2 plays a pivotal role in neuronal excitability and is regulated by a variety of known and unknown extrinsic factors. The canonical accessory subunit of Kv1.2, Kvβ, promotes N-type inactivation and cell surface expression of the channel. We recently reported that a neutral amino acid transporter, Slc7a5, alters the function and expression of Kv1.2. In the current study, we investigated the effects of Slc7a5 on Kv1.2 in the presence of Kvβ1.2 subunits. We observed that Slc7a5-induced suppression of Kv1.2 current and protein expression was attenuated with cotransfection of Kvβ1.2. However, gating effects mediated by Slc7a5, including disinhibition and a hyperpolarizing shift in channel activation, were observed together with Kvβ-mediated inactivation, indicating convergent regulation of Kv1.2 by both regulatory proteins. Slc7a5 influenced several properties of Kvβ-induced inactivation of Kv1.2, including accelerated inactivation, a hyperpolarizing shift and greater extent of steady-state inactivation, and delayed recovery from inactivation. These modified inactivation properties were also apparent in altered deactivation of the Kv1.2/Kvβ/Slc7a5 channel complex. Taken together, these findings illustrate a functional interaction arising from simultaneous regulation of Kv1.2 by Kvβ and Slc7a5, leading to powerful effects on Kv1.2 expression, gating, and overall channel function.

Chlordane is a worldwide banned organochlorine insecticide because of its hazard to animal and human health. It is also a persistent organic pollutant, which can affect either the soil or the aquatic life. The same applies to other chlorinated cyclodiene insecticides, such as dieldrin and aldrin. In turn, organofluorine compounds have a widespread use in agriculture. Therefore, density functional calculations and docking studies showed that the bioisosteric replacement of chlorines in the above-mentioned compounds by fluorines improves some physicochemical parameters used to estimate the toxicity and environmental risk of these compounds, as well as the ligand-enzyme (GABAA receptor-chloride channel complex) interactions related to their insecticidal activity. This work is an effort to provide an improved new class of organofluorine pesticides.

Ion channels control the membrane potential and mediate transport of ions across membranes. Archetypical physiological functions of ion channels include processes such as regulation of neuronal excitability, muscle contraction, or transepithelial ion transport. In that regard, transient receptor potential ion channel polycystin 2 (TRPP2) is remarkable, because it controls complex morphogenetic processes such as the establishment of properly shaped epithelial tubules and left-right-asymmetry of organs. The fascinating question of how an ion channel regulates morphogenesis has since captivated the attention of scientists in different disciplines. Four loosely connected key insights on different levels of biological complexity ranging from protein to whole organism have framed our understanding of TRPP2 physiology: 1) TRPP2 is a non-selective cation channel; 2) TRPP2 is part of a receptor-ion channel complex; 3) TRPP2 localizes to primary cilia; and 4) TRPP2 is required for organ morphogenesis. In this review, we will discuss the current knowledge in these key areas and highlight some of the challenges ahead.

SummaryThe sodium leak channel (NALCN) is essential for survival in mammals: NALCN mutations are life-threatening in humans and knockout is lethal in mice. However, the basic functional and pharmacological properties of NALCN have remained elusive. Here, we found that the robust function of NALCN in heterologous systems requires co-expression of UNC79, UNC80 and FAM155A. The resulting NALCN channel complex is constitutively active, conducts monovalent cations but is blocked by physiological concentrations of extracellular divalent cations. Our data support the notion that NALCN is directly responsible for the increased excitability observed in a variety of neurons in reduced extracellular Ca2+. Despite the smaller number of voltage-sensing residues in the putative voltage sensors of NALCN, the channel complex shows voltage-dependent modulation of the constitutive current, suggesting that voltage-sensing domains can give rise to a broader range of gating phenotypes than previously anticipated. Our work points towards formerly unknown contributions of NALCN to neuronal excitability and opens avenues for pharmacological targeting.HighlightsFunction of NALCN requires UNC79, UNC80 and FAM155AThe complex is permeable to monovalent cations, but is blocked by divalent cationsThe complex displays a constitutively active, voltage-modulated current phenotypePositively charged side chains in S4 of NALCN VSD I and II confer voltage sensitivity

Protein translocating Cag type IV secretion system of Helicobacter pylori is a diverse multi-protein complex. Here, we have characterized one of its key subunit CagW to identify its interacting partners. Our results demonstrate for the first time that this VirB6 homologue interacts with the substrate of the secretion system CagA. CagW forms multimer and its absence affects cellular levels of pilus forming components, CagL, CagI and CagH. Our results support the notion that the protein is essential for the transport of CagA across the bacterial membrane barrier and would aid in improving our understanding of structural and functional aspects of the inner membrane part of Cag-T4SS channel complex for the passage of substrate CagA.

The Bengal Fan has attracted extensive attention from the oil industry because of its hydrocarbon reservoir potential. This paper characterizes the architectural elements and stratigraphy of the Upper Miocene-Pliocene Bengal Fan by high-resolution 3D seismic data. Seismic facies and strata slice technologies are applied to identify architectural elements. Six seismic facies are classified and interpreted as mass-transport deposits, channel complex including incised channel, leveed channel and sinuous channel, lobe complex, and hemipelagic deposits. Two seismic sequences and five internal sequences are divided according to the vertical evolution of deepwater sedimentary elements. By understanding and identifying the architectural elements and stratigraphy of the deepwater fan, we can propose potential drilling sequences of oil and gas reservoirs.

In northeastern Montana, fossil localities in the Garbani Channel Complex and other early Paleocene (Puercan 3 Interval Zone) localities are preserved in the Tullock Member of the Fort Union Formation. They document an early phase in the recovery of the terrestrial fauna of the North American Western Interior after the mass extinction marking the Cretaceous-Paleogene (K-Pg) boundary. The cimolestids Puercolestes simpsoni and Betonnia tsosia were typified on fragmentary jaws and isolated teeth found in Puercan 2 and 3 Interval Zones (Pu2, Pu3) in the Nacimiento Formation, San Juan Basin, New Mexico. The available samples of these genera from both New Mexico and Montana are small and dominantly consist of isolated teeth. Characters of upper cheek teeth, P4 and M1–M3, justify provisional recognition of Puercolestes sp. cf. Pu. simpsoni and the somewhat smaller Betonnia sp. cf. Be. tsosia in Pu3 local faunas in the Tullock Member. In contrast, discovery of characters distinguishing the isolated lower cheek teeth, p4s and m1–m3s, of these species must await recovery of dentulous dentaries documenting the patterns of morphological variation of their lower dentitions. Fossils from the Tullock Member add support to the current interpretation that cimolestids were taxonomically diverse and geographically widespread but relatively rare members of the faunas of the North American Western Interior during approximately the first million years of the Paleocene.

"This prediction demonstrates an inclusive investigation on" single-phase and two- phase pressure drop properties and flows boiling" instabilities in micro-channels to resume the concepts in the boiling heat transfer tests". The predictions of "single-phase and two- phase heat transfers" in the aluminum micro-channel heat sink have been investigated". "Different heat fluxes and different mass fluxes have been applied "(each mass flow rate under numerous heats fluxes) in an aluminum parallel channel test piece is tested". "It was built up from a piece of aluminum," twenty-five mm wide by twenty-five mm long and ten mm high"."R113 working fluid temperature was constant (25°C) for all prediction tests; "Therefore the heat applies have been applied "in the ranges of (40-600 Watts) "The processes and iteration loops have reached for the prediction heat transfer properties "for three mass flow rates are (0.0125;0.015 and 0.0175 kg/s) "respectively;" and another heat transfer properties. "The aluminum micro-channels heat sink" with 0.5 mm channel height and 0.5 mm channel width "is heated via a wire electrical heater device". "The single-phase and two-phase flows are important parameters" for geometrical configuration of the aluminum micro-channels under variations heat applied". The purpose of this investigation is to explore the relationship between "prediction heat transfer coefficients and mini-scale heat sink geometrical configuration". Heat-transfer coefficients and pressure drops are investigated"." For sub-cooled and saturated boiling data acquired with Single-phase and boiling flows," The single-phase consequences are seen to be location-following, regular with a fully developed laminar flow. All the prediction boiling heat transfer coefficients are seen to have reasonably relied on as mass fraction and mass flux"."" Nevertheless, some are seen to have relied on heat flux whereas others are not. The convective boiling consisting is seen to have a boiling heat-transfer coefficient that is moderately relied on mass flow rate, gas mass fraction, and heat applied"." The prediction work presented here provides one of the first investigations into how to get single-phase" and two-phase properties" data via computer programming. In the end, "the single-phase and two-phase" heat transfer coefficients are reported" for square aluminum micro-channels heat sink under" boiling tests".

Organochlorine pesticides have been extensively used in the past, but due to both their environmental persistence and neurotoxicity their use has been banned or greatly reduced in the last decades. Pyrethroids are among the most used insecticides. The main effects of both organochlorines and pyrethroids are on the nervous system by interference with different ion channels; DDT and analogs, and pyrethroids interfere mainly sodium channels causing both central and peripheral nervous effects; lindane and cyclodienes mainly the gamma-aminobutyric acid (GABA) A -receptor–chloride channel complex. In addition, developmental neurotoxic effects have been demonstrated in animals perinatally exposed to either DDT and analogs or pyrethroids. Data in humans do not show convincing evidence of such effects. Also some epidemiological studies indicate a relation between parkinsonism and exposure to organochlorines or pyrethroids, but experimental data do not strongly support a causative role of these compounds.

The excited hyperon Λ ( 1405 ) is the important building block for kaonic nuclei which are a nuclear many-body system with anti-kaons. We have been investigating the Λ ( 1405 ) resonance with the coupled-channel Complex Scaling Method (ccCSM) in which the Λ ( 1405 ) is treated as a hadron-molecular state of a K ¯ N – πΣ coupled system. We use a K ¯ N (– πY ) potential based on the chiral SU(3) theory. In this article, we report the double-pole nature of the Λ ( 1405 ) , which is a characteristic property predicted by many studies with chiral SU(3)-based models. With the help of the complex-range Gaussian basis in ccCSM, we have found successfully another pole besides a pole near the K ¯ N threshold (called higher pole) which was found in our previous work with the real-range Gaussian basis. The new pole (called lower pole) is found far below K ¯ N threshold: ( M , − Γ / 2 ) = ( 1395 , − 138 ) MeV when f π = 110 MeV . In spite of so broad width of the lower-pole state, the state is clearly identified with good separation from continuum states, since the oscillatory behavior of the continuum states is improved owing to the complex-range Gaussian basis. Analyzing the ccCSM wave function of the lower pole, we have revealed explicitly that the lower-pole state is dominated by the πΣ component rather than the K ¯ N component. We have confirmed that the ccCSM wave function is correctly connected to the asymptotic form of the resonance wave function. Estimating the meson–baryon mean distance for the lower-pole state which involves a large decay width, the obtained value has a large imaginary part comparable to a real part. Therefore, the mean-distance of the lower-pole state is difficult to be interpreted intuitively. Such a nature of the lower pole is different from that of the higher pole. In addition, we have investigated the origin of the appearance of the lower pole. The lower pole is confirmed to be generated by the energy dependence attributed to the chiral dynamics, by comparing the result of an energy-independent potential.

K+ channels containing Kv4.2 and Kv4.3 pore-forming subunits mediate most of the subthreshold-operating somatodendritic A-type K+ current in CNS neurons. These channels are believed to be important in regulating the frequency of repetitive firing, the backpropagation of action potential into dendrites, and dendritic integration and plasticity. Moreover, they have been implicated in several diseases from pain to epilepsy and autism spectrum disorders. The lack of toxins that specifically and efficiently block these channels has hampered studies aimed at confirming their functional role and their involvement in disease. AmmTX3 and other related members of the α-KTX15 family of scorpion toxins have been shown to block the A-type K+ current in cultured neurons, but their specificity has been questioned because the toxins do not efficiently block the currents mediated by Kv4.2 or Kv4.3 subunits expressed in heterologous cells. Here we show that the high-affinity blockade of Kv4.2 and Kv4.3 channels by AmmTX3 depends on the presence of the auxiliary subunits DPP6 and DPP10. These proteins are thought to be components of the Kv4 channel complex in neurons and to be important for channel expression in dendrites. These studies validate the use of AmmTX3 as a blocker of the Kv4-mediated A-type K+ current in neurons.

Mechanotransduction, the conversion of mechanical forces into biological signals, plays critical roles in various physiological and pathophysiological processes in mammals, such as conscious sensing of touch, pain, and sound, as well as unconscious sensing of blood flow-associated shear stress, urine flow, and bladder distention. Among the various molecules involved in mechanotransduction, mechanosensitive (MS) cation channels have long been postulated to represent one critical class of mechanotransducers that directly and rapidly converts mechanical force into electrochemical signals. Despite the awareness of their functional significance, the molecular identities of MS cation channels in mammals had remained elusive for decades till the groundbreaking finding that the Piezo family of genes, including Piezo1 and Piezo2, constitutes their essential components. Since their identification about 6 years ago, tremendous progress has been made in understanding their physiological and pathophysiological importance in mechanotransduction and their structure–function relationships of being the prototypic class of mammalian MS cation channels. On the one hand, Piezo proteins have been demonstrated to serve as physiologically and pathophysiologically important mechanotransducers for most, if not all, mechanotransduction processes. On the other hand, they have been shown to form a remarkable three-bladed, propeller-shaped homotrimeric channel complex comprising a separable ion-conducting pore module and mechanotransduction modules. In this chapter, we review the major advancements, with a particular focus on the structural and biophysical features that enable Piezo proteins to serve as sophisticated MS cation channels for force sensing, transduction, and ion conduction.

This Focus Issue highlights research into cell-specific regulation of store-operated calcium entry through the ORAI/STIM channel complex. Understanding the properties of these channels and how ORAI activity is regulated will lead to a better molecular view of immune cell function and diseases involving the immune system.

Calmodulin (CaM), a bi-partite protein, binding to the A-B module, a bi-partite target, affect the function of Kv7.2 subunits, which are the main component of the non-inactivating K+ M-current, a key controller of neuronal excitability. Simultaneous binding to helix A and B is crucial for trafficking to the plasma membrane, and mediates Ca2+-dependent inhibition of channel function. We have resolved the [CaM]/[AB-Kv7.2] complex by NMR and characterized the influence of Ca2+ on the structure. The results suggest a reorientation of A-B helices triggered by Ca2+. How this structural change may propagate to affect gating will be discussed.

The composition of fish, their location and movements in the channel, channel depressions, and flood waters of the lower reaches of the Irtysh River are investigated. This study is conducted with computer sonar systems used for different purposes. Diurnal and seasonal dynamics of movements of the fish and the abundance and composition of fish aggregations are revealed in the studied sites. The biological unity of the fish community of the floodplain-channel complex is demonstrated.

Hair cells are the mechanosensory cells of the inner ear. Mechanotransduction channels in hair cells are gated by tip links. The molecules that connect tip links to transduction channels are not known. Here we show that the transmembrane protein TMIE forms a ternary complex with the tip-link component PCDH15 and its binding partner TMHS/LHFPL5. Alternative splicing of the PCDH15 cytoplasmic domain regulates formation of this ternary complex. Transducer currents are abolished by a homozygous Tmie-null mutation, and subtle Tmie mutations that disrupt interactions between TMIE and tip links affect transduction, suggesting that TMIE is an essential component of the hair cell's mechanotransduction machinery that functionally couples the tip link to the transduction channel. The multi-subunit composition of the transduction complex and the regulation of complex assembly by alternative splicing is likely critical for regulating channel properties in different hair cells and along the cochlea's tonotopic axis.

The KCNQ1 voltage-gated potassium channel and its auxiliary subunit KCNE1 play a crucial role in the regulation of the heartbeat. The stoichiometry of KCNQ1 and KCNE1 complex has been debated, with some results suggesting that the four KCNQ1 subunits that form the channel associate with two KCNE1 subunits (a 4∶2 stoichiometry), while others have suggested that the stoichiometry may not be fixed. We applied a single molecule fluorescence bleaching method to count subunits in many individual complexes and found that the stoichiometry of the KCNQ1 - KCNE1 complex is flexible, with up to four KCNE1 subunits associating with the four KCNQ1 subunits of the channel (a 4∶4 stoichiometry). The proportion of the various stoichiometries was found to depend on the relative expression densities of KCNQ1 and KCNE1. Strikingly, both the voltage-dependence and kinetics of gating were found to depend on the relative densities of KCNQ1 and KCNE1, suggesting the heart rhythm may be regulated by the relative expression of the auxiliary subunit and the resulting stoichiometry of the channel complex.

KCNQ1 is the pore-forming subunit of a channel complex whose expression and function have been rather well characterized in the heart. Almost 300 mutations of KCNQ1 have been identified in patients and a vast majority of the described mutations are linked to the long QT syndrome. Only a few mutations are linked to other pathologies such as atrial fibrillation and the short QT syndrome. However, a considerable amount of work remains to be done to get a clear picture of the molecular mechanisms responsible for the pathogenesis related to each mutation. The present review gives three examples of recent studies towards this goal and illustrates the diversity of the molecular mechanisms involved.

Hydrocarbon fields consisting of turbidite deposits are commonly more complex than anticipated because of fine-scale sedimentary heterogeneities, which complicate the reservoir characteristics. This is particularly evident in turbiditic channel complexes with lateral channel migration. The creation of fine-scale models is founded on high-resolution seismic data, incorporating all available data together with concepts of the internal reservoir architecture. The model is essential for understanding the impact of these phenomena on reservoir characteristic distributions. The lateral extents and a real distribution of heterogeneity are still unknown; thus, our modeling workflow is incorporated into an uncertainty chain to identify and measure all uncertainties with a possible effect on static connectivity. Internal channel complex fill is composed of multiple individual (elementary) channel stacks formed during repeated erosion-deposition cycles. These elementary structures allow sand transport through deep-sea areas and the preservation of slumps and slides on channel borders, resulting in the formation of internal heterogeneities. The sideways and downdip movement of elementary channels in turbidite complexes show two typical channel patterns: lateral migration and vertical stacking. The spatial distribution of slide heterogeneities is therefore constrained by the different channel patterns. Distinguishing between these two patterns provides an understanding of heterogeneity distributions and the resulting differences in static connectivity. These contrasts can be explained as distinct preservation rates of mass-transport slide sediments within elementary channels and can thus be included in reservoir models to define preferential zones of heterogeneity preservation along turbidite complexes.

Summary One important application of time frequency analysis is the identification of channel complex. However, conventional time frequency analysis methods suffer from low resolution which sometimes leads to relative terrible interpretation results. In this paper, a novel time frequency analysis approach called inversion spectral decomposition (ISD) is applied to solve these problems. ISD is proposed via inversion strategy and has a higher resolution. In the identification of channel complex, ISD provides not only more detailed time frequency content in time frequency amplitude spectrum than conventional time frequency analysis methods, but also additional phase information, which gives another perspective to identify channel complex, thus reducing the uncertainty in interpretation. In the test of 3D synthetic data, both Gabor transform and ISD are applied to generate time slices. Gabor transform only identifies the middle section of channel complex while ISD clearly identifies the whole channel complex with legible details. Furthermore, ISD provides additional phase information, further confirming the reliability in interpretation. Finally, ISD is applied to a 3D real data, and exhibits an outstanding performance.

The biogenesis of K ATP channels provides an interesting example of the assembly of structurally very different membrane protein subunits into a heterooligomeric complex. This review summarizes our current knowledge with respect to the protein domains driving heteromultimeric assembly in the endoplasmic reticulum, quality control, as well as the determinants and kinetics of subcellular sorting of the K ATP channel complex. The impact of disease-associated mutations on K ATP channel biogenesis is discussed.

Voltage-gated Ca(2+) channels (VGCCs) are important in regulating a variety of cellular functions in neurons. It remains poorly understood how VGCCs with different functions are sorted within neurons. Here we show that the t-complex testis-expressed 1 (tctex1) protein, a light-chain subunit of the dynein motor complex, interacts directly and selectively with N- and P/Q-type Ca(2+) channels, but not L-type Ca(2+) channels. The interaction is insensitive to Ca(2+). Overexpression in hippocampal neurons of a channel fragment containing the binding domain for tctex1 significantly decreases the surface expression of endogenous N- and P/Q-type Ca(2+) channels but not L-type Ca(2+) channels, as determined by immunostaining. Furthermore, disruption of the tctex1-Ca(2+) channel interaction significantly reduces the Ca(2+) current density in hippocampal neurons. These results underscore the importance of the specific tctex1-channel interaction in determining sorting and trafficking of neuronal Ca(2+) channels with different functionalities.

I(Ks) voltage-gated K(+) channels contain four pore-forming KCNQ1 subunits and MinK accessory subunits in a number that has been controversial. Here, I(Ks) channels assembled naturally by monomer subunits are compared to those with linked subunits that force defined stoichiometries. Two strategies that exploit charybdotoxin (CTX)-sensitive subunit variants are applied. First, CTX on rate, off rate, and equilibrium affinity are found to be the same for channels of monomers and those with a fixed 2:4 MinK:KCNQ1 valence. Second, 3H-CTX and an antibody are used to directly quantify channels and MinK subunits, respectively, showing 1.97 +/- 0.07 MinK per I(Ks) channel. Additional MinK subunits do not enter channels of monomeric subunits or those with fixed 2:4 valence. We conclude that two MinK subunits are necessary, sufficient, and the norm in I(Ks) channels. This stoichiometry is expected for other K(+) channels that contain MinK or MinK-related peptides (MiRPs).

Multiple protein kinase C (PKC) isozymes are present in neurons, where they regulate a variety of cellular functions. Due to the lack of specific PKC isozyme inhibitors, it remains unknown how PKC acts on its selective target(s) and achieves its specific actions. Here we show that a PKC binding protein, enigma homolog (ENH), interacts specifically with both PKCepsilon and N-type Ca2+ channels, forming a PKCepsilon-ENH-Ca2+ channel macromolecular complex. Coexpression of ENH facilitated modulation of N-type Ca2+ channel activity by PKC. Disruption of the complex reduced the potentiation of the channel activity by PKC in neurons. Thus, ENH, by interacting specifically with both PKCepsilon and the N-type Ca2+ channel, targets a specific PKC to its substrate to form a functional signaling complex, which is the molecular mechanism for the specificity and efficiency of PKC signaling.

We present a sub-nanometer cryo-EM structure the Kv1.2 channel complex in a lipid bilayer, obtained from protein reconstituted into liposomes. Using this system we expect that the voltage-gated channels can be subjected to physiological membrane potentials and ion gradients. Our present map was obtained at zero membrane potential for comparison with X-ray structures, but we report progress in establishing and verifying the presence of membrane potentials in the small (∼40 nm) liposomes used for cryo-EM imaging.

A novel, cell-surface protein essential for Ca(2+) release-activated Ca(2+) (CRAC) channel function has been identified through independent genome-wide screens. This huge advance will enable molecular dissection of the CRAC channel complex, moving the field beyond Icrac signature to structure.

N-type and P/C-type inactivation are firmly established mechanisms of inactivation in voltage-gated K+ (Kv channels). However, Kv4.x channel complexes, which undergo fast preferential closed-state inactivation (CSI; Fineberg et al., 2012, JGP 140.5:513-527), appear to use a distinct but unknown inactivation mechanism. Previously, we hypothesized that a weak interaction between the voltage sensing domain and the intracellular activation gate underlies CSI (Bahring & Covarrubias, 2011, J Physiol 589:461-79). Thus, CSI is essentially governed by the intracellular activation gate, which fails to open and adopts an inactivated conformation. To directly test this hypothesis, we investigated the heterologously expressed Kv4.1 ternary channel complex including accessory subunits KChIP1 and DPP6, and exploited the “trap-door” paradigm of the activation gate. The results show that Kv4.1 inactivation traps intracellularly applied quaternary ammonium blockers (bTBuA and TBuA) inside the channel's pore. The trapped blockers can only escape if the channels are opened again by subsequent depolarizations. By contrast, inactivation cannot trap TEA, whose binding kinetics is faster than that of channel gating. Moreover, under identical conditions, a Shaker Kv channel (ShB-T449K) known to exhibit fast P/C-type inactivation cannot trap bTBuA. These findings conclusively suggest that the intracellular activation gate of the Kv4.1 ternary channel complex plays a novel dual role, controlling both activation and inactivation. Supported in part by NIH grant R01 NS032337 (MC).

The last session of the conference focused on studies which showed the formation of a channel complex consisting of KvLQT1 (a classical K+ channel protein with six transmembrane regions with one pore structure) and another component, termed minK or IsK (a small protein with a single transmembrane domain) resulting in heteromeric channel with new properties. A number of reports have suggested that this channel complex has importance in certain disease states. Michel Lazdunski (CNRS, Valbonne, France) suggested that the C- terminal end of minK can interact with the pore region of KvLQT1 resulting in prolonged openings with smaller single-channel conductance. Andreas Busch (University of Tubingen, Germany) concentrated in his presentation on the pharmacological properties of the channel complex and the contribution of the IsK protein to these properties; for example, KvLQT1 on its own in the membrane is much less sensitive to block by 293B when compared to the channel complex.One of the highlights of the IPCC was the presentation of the keynote lecture by Hans Meves (University of the Saarland, Homburg, Germany). He reviewed K+ channel research from his personal viewpoint starting from work in the early 50s about the doubts in the research community whether special channels for K+ exist to end with the description of single channel, channel structures, as well as specific roles of K+ channels in cell function. One of his messages was to celebrate the tenth anniversary of the first K+ channel gene cloned from Drosophila independently from three different groups around Lily Jan (University of California, San Francisco, USA), Mark Tanouye (then at CalTech, Pasadena, USA now at the University of California, Berkeley, USA), and Olaf Pongs (then at Ruhr-University, Bochum, Germany now at the Center for Molecular Biology, Hamburg, Germany).During the poster sessions research was presented on the regulation/modulation of K+ channels by intracellular components such as ATP, G proteins and β-subunits, etc. Several new toxins and other substances were introduced at the meeting that might help to elucidate channel structure or might be helpful in being used as model drugs to design better and more specific drugs for certain K+ channel types. This meeting clearly showed that K+ channel research is still growing and has not reached its peak yet. Future developments will further increase our knowledge about K+ channels, how they function and what role they play in a variety of different cell types.

Cardiac myocytes use Ca2+ not only in excitation-contraction coupling but also as a signaling molecule for cardiac growth. It is however unclear how Ca2+ triggers signaling in cardiac myocytes in the presence of the rapid and large Ca2+ fluctuations that occur during excitation-contraction coupling. We have recently reported that stromal interaction molecule 1 (STIM1), a calcium sensor in the sarcoplasmic reticulum, is a critical element in promoting cardiomyocyte growth through the control of a previously unrecognized sarcolemmal voltage-independent current. Our goal was to characterize the plasma membrane partners that contribute to STIM1-dependent currents in normal and hypertrophied adult cardiac myocytes. We firstly characterized the expression profile of TRPCs and ORAIs proteins in both normal and hypertrophied ventricular myocytes from abdominal aortic banded rats. The expression of TRPC1, 3, 4, 5 and 6 and of ORAI1 - 3 was identified with an up-regulation of TRPC1 in hypertrophied cells. We then used a non-viral method to deliver cy3-tagged siRNAs to ventricular myocytes to knock-down the candidate channels. The cardiac myocytes were isolated and whole cell patch-clamp technique as well as Fura-2 imaging were performed to measure the currents in cy3-labelled and in control cardiac myocytes. Our data demonstrated that the drug-inducible STIM1-dependent store-operated calcium entry was marginal in normal myocytes but was enhanced in hypertrophied myocytes. In addition, a basal inwardly rectifying current was observed in hypertrophied but not in control myocytes. This spontaneous current was recorded in the absence of calcium store depletion, required STIM1 expression and meets the characteristics of Arachidonate-Regulated Calcium selective (ARC) channels. ORAI silencing completely inhibited both store-dependent and store-independent currents suggesting the critical implication of ORAIs whereas TRPCs were only marginally involved. In conclusion, ORAI channels are involved in STIM1-dependent currents observed in hypertrophied adult cardiac myocytes. In addition to store-operated calcium entry, the STIM1/ORAI complex provides an alternative, store-independent pathway for agonist-activated Ca2+ entry.

Abstract During the last decade, seismic-based studies have become fundamental for detailed and objective descriptions of reservoir depositional elements, a necessary condition for building robust stratigraphic frameworks and sedimentological interpretations unbiased by questionable analogues or existing models. A close integration of sedimentary geology and geophysical interpretation is presented here to demonstrate that these two disciplines can support each other to provide a powerful tool for predicting reservoir sandstones architecture. The work was carried out on the deep-water sequences of the Ghanaian offshore, which have been interpreted as weakly confined channel complexes (WCCC) deposited at the base of slope. WCCC are approximately 150–300m thick and 10–15km wide and made of stacked, laterally amalgamated channels and lobes vertically separated by shale-prone intercalations. Detailed interpretation of individual seismic reflections followed by an elastic inversion and Bayesian facies classification calibrated with 3 wells allowed to identify several distinct small-scale composite channel fills and lobes forming sand bodies 1–2km wide and 15–25m thick. High and low-sinuosity sand bodies compensate each other and stack vertically, migrating progressively from West to East. Furthermore, some channel-fills show a marked aggradational pattern. The overall depositional pattern is believed to represent a progressive decrease in sediment supply leading to the de-activation of the system. Despite the key sand bodies were correctly identified on seismic amplitudes and well-logs through conventional, "qualitative" approaches, their subsequent "quantitative" imaging by elastic inversion and facies (shale, brine and gas) probabilities allowed to clarify many uncertainties in the stratigraphic and sedimentological framework, particularly where the marked AVO fluid effect inevitably interfered with the initial, purely sedimentological interpretation. High-res biostratigraphic data further confirmed the inferred physical-stratigraphic and litho-fluid framework established through the integration of seismic sedimentology and quantitative geophysics.