Abstract:
:ATP-sensitive K(+)-channels link metabolism and excitability in neurons, myocytes, and pancreatic islets. Mutations in the pore-forming subunit (Kir6.2; KCNJ11) cause neonatal diabetes, developmental delay, and epilepsy by decreasing sensitivity to ATP inhibition and suppressing electrical activity. Mutations of residue G53 underlie both mild (G53R,S) and severe (G53D) forms of the disease. All examined substitutions (G53D,R,S,A,C,F) reduced ATP-sensitivity, indicating an intolerance of any amino acid other than glycine. Surprisingly, each mutation reduces ATP affinity, rather than intrinsic gating, although structural modeling places G53 at a significant distance from the ATP-binding pocket. We propose that glycine is required in this location for flexibility of the distal N-terminus, and for an induced fit of ATP at the binding site. Consistent with this hypothesis, glycine substitution of the adjacent residue (Q52G) partially rescues ATP affinity of reconstituted Q52G/G53D channels. The results reveal an important feature of the noncanonical ATP-sensing mechanism of K(ATP) channels.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Koster JC,Kurata HT,Enkvetchakul D,Nichols CGdoi
10.1529/biophysj.108.138685subject
Has Abstractpub_date
2008-11-15 00:00:00pages
4689-97issue
10eissn
0006-3495issn
1542-0086pii
S0006-3495(08)78608-9journal_volume
95pub_type
杂志文章abstract::The electrostatic free energies of native and acetylated lysozymes were computed by the fixed charge model (Tanford, C., and J. G. Kirkwood, 1957, J. Am. Chem. Soc., 79:5333-5339). For each computation, the charges were transformed into a sphere of fixed radius without changing their depths or the distance between cha...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84302-1
更新日期:1983-12-01 00:00:00
abstract::Using homonuclear (1)H NOESY spectra, with chemical shifts, (3)JH(N)H(α) scalar couplings, residual dipolar couplings, and (1)H-(15)N NOEs, we have optimized and validated the conformational ensembles of the amyloid-β 1-40 (Aβ40) and amyloid-β 1-42 (Aβ42) peptides generated by molecular dynamics simulations. We find t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.04.056
更新日期:2013-06-18 00:00:00
abstract::In recent experimental reports, robust circadian oscillation of the phosphorylation level of KaiC has been reconstituted by incubating three cyanobacterial proteins, KaiA, KaiB, and KaiC, with ATP in vitro. This reconstitution indicates that protein-protein interactions and the associated ATP hydrolysis suffice to gen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.02.036
更新日期:2010-06-02 00:00:00
abstract::Constant electric fields and constant ion currents are often considered in theories of ion transport. Therefore, it is important to understand the validity of these helpful concepts. The constant field assumption requires that the charge density of permeant ions and flexible polar groups is virtually voltage independe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77242-5
更新日期:1999-02-01 00:00:00
abstract::Microbial capsules are important for virulence, but their architecture and physical properties are poorly understood. The human pathogenic fungus Cryptococcus neoformans has a large polysaccharide capsule that is necessary for virulence and is the target of protective antibody responses. To study the C. neoformans cap...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.04.043
更新日期:2009-08-19 00:00:00
abstract::We present in this report a detailed structural study of calf gamma-crystallins both in the solid state and in solution by the newly developed technique of near-infrared (IR) Fourier transform (FT)-Raman spectroscopy as well as by the conventional Raman method. In comparison with conventional laser Raman spectroscopy,...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82071-9
更新日期:1991-08-01 00:00:00
abstract::Two mechanisms have been proposed to account for solute permeation of lipid bilayers. Partitioning into the hydrophobic phase of the bilayer, followed by diffusion, is accepted by many for the permeation of water and other small neutral solutes, but transient pores have also been proposed to account for both water and...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79575-9
更新日期:1996-01-01 00:00:00
abstract::Fluorescent labels are often used in bioassays as a means to detect and characterize ligand-receptor binding. This is due in part to the inherently high sensitivity of fluorescence-based technology and the relative accessibility of the technique. There is often little concern raised as to whether or not the fluorescen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.127688
更新日期:2008-07-01 00:00:00
abstract::We used micron-sized latex spheres to probe the phase state and the viscoelastic properties of dimyristoylphosphatidylcholine (DMPC) bilayers as a function of temperature. One or two particles were manipulated and stuck to a DMPC giant vesicle by means of an optical trap. Above the fluid-gel main transition temperatur...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76296-5
更新日期:2000-07-01 00:00:00
abstract::The shapes of fluorescence induction curves in spinach chloroplasts, measured using double-flash pump-probe techniques, are shown to depend on the duration of the actinic flashes. For flash durations tau(0) = 2 mus, the variable fluorescence F(nu) grows exponentially (or nearly so) with increasing fluence J of the a...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82233-0
更新日期:1991-02-01 00:00:00
abstract::Nanopatterned surfaces are believed to kill bacteria through physical deformation, a mechanism that has immense potential against biochemical resistance. Because of its elusive nature, this mechanism is mostly understood through biophysical modeling. Problematically, accurate descriptions of the contact mechanics and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.12.003
更新日期:2021-01-19 00:00:00
abstract::Nuclear magnetic resonance (NMR) measurements provide both structural and dynamical information about the molecules in which nuclear resonances are observed. This manuscript addresses NMR relaxation of water protons in protein powder systems. Inclusion of magnetic communication between the water proton spins and prote...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(80)84912-5
更新日期:1980-10-01 00:00:00
abstract::Nerve growth factor (NGF) mimics play an important role for therapies that target the receptor tyrosine kinase A (trkA). The N-terminal fragment of the NGF (N-term@NGF) was previously demonstrated to be an important determinant for affinity and specificity in the binding to trkA. Here we use a variety of computational...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.083519
更新日期:2006-09-15 00:00:00
abstract::In an accompanying paper we reported the use of differential scanning calorimetry and optical densitometry to characterize the melting and aggregation of 160 bp fragments of calf thymus DNA during heating in the presence of divalent metal cations. Aggregation is observed as thermal denaturation begins and becomes more...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80134-7
更新日期:1995-12-01 00:00:00
abstract::We expressed rod-type homotetrameric cyclic nucleotide-gated (CNGA1) channels in Xenopus oocytes and studied activation by photolysis-induced jumps of the 3',5'-cyclic guanosine monophosphate (cGMP) concentration and by voltage steps. cGMP jumps to increasing concentrations up to the EC50 value of 46.5 microM decelera...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.078667
更新日期:2006-05-01 00:00:00
abstract::The ejection of DNA from a bacterial virus (i.e., phage) into its host cell is a biologically important example of the translocation of a macromolecular chain along its length through a membrane. The simplest mechanism for this motion is diffusion, but in the case of phage ejection a significant driving force derives ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.070532
更新日期:2006-07-15 00:00:00
abstract::A detailed description of the construction and performance of a variable frequency cross-correlation phase fluorometer is reported. The phase fluorometer operates over the frequency range 1-160 MHz with a maximum resolution of a few picoseconds. The effects of distortions introduced by the light modulator and the nonl...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84305-7
更新日期:1983-12-01 00:00:00
abstract::We describe a statistical mechanical model for lipid-cholesterol mixtures in the P beta' (ripple) phase of lipid bilayers. The model is a simple extension of an earlier model for the ripple phase in pure lipid bilayers. The extension consists of adding a degree of freedom to allow for the occupation of underlying latt...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81506-6
更新日期:1993-05-01 00:00:00
abstract::One of the unusual properties of elastin is its ability to coacervate, which has been proposed to play an important role in the alignment of monomeric elastin for cross-linking into the polymeric elastin matrix. The temperature at which this transition takes place depends on several factors including protein concentra...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.110809
更新日期:2007-11-15 00:00:00
abstract::We report here several unusual features of inactivation of the rat Kv2.1 delayed rectifier potassium channel, expressed in Xenopus oocytes. The voltage dependence of inactivation was U-shaped, with maximum inactivation near 0 mV. During a maintained depolarization, development of inactivation was slow and only weakly ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77888-9
更新日期:1998-04-01 00:00:00
abstract::The extracellular space of the brain is the heterogeneous porous medium formed by the spaces between the brain cells. Diffusion in this interstitial space is the mechanism by which glucose and oxygen are delivered to the brain cells from the vascular system. It is also a medium for the transport of certain information...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.095547
更新日期:2007-05-15 00:00:00
abstract::Chromatin is partitioned on multiple length scales into subcompartments that differ from each other with respect to their molecular composition and biological function. It is a key question how these compartments can form even though diffusion constantly mixes the nuclear interior and rapidly balances concentration gr...
journal_title:Biophysical journal
pub_type: 杂志文章,评审
doi:10.1016/j.bpj.2018.03.011
更新日期:2018-05-22 00:00:00
abstract::The adhesion of giant unilamellar phospholipid vesicles to planar substrates coated with extracellular matrix mimetic cushions of hyaluronan is studied using quantitative reflection interference contrast microscopy. The absolute height of the vesicle membrane at the vicinity of the substrate is measured by considering...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.105544
更新日期:2007-11-01 00:00:00
abstract::The group-additive decomposition of the unfolding free energy of a protein in an osmolyte solution relative to that in water poses a fundamental paradox: whereas the decomposition describes the experimental results rather well, theory suggests that a group-additive decomposition of free energies is, in general, not va...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.08.011
更新日期:2013-09-17 00:00:00
abstract::An approach is introduced to characterize conformational ensembles of intrinsically unstructured peptides on the atomic level using two-dimensional solid-state NMR data and their combination with molecular dynamics simulations. For neurotensin, a peptide that binds with high affinity to a G-protein coupled receptor, t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.059964
更新日期:2005-09-01 00:00:00
abstract::Comparison of the electron spin resonance spectra of phosphatidylcholines spin-labeled in the sn-2 chain at a position close to the polar region and close to the methyl terminus indicate that symmetrical saturated diacyl phosphatidylcholines with odd and even chain lengths from 13 to 20 C-atoms (and probably also 12 C...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80009-3
更新日期:1995-10-01 00:00:00
abstract::The electrophysiological properties of the cation channel of the purified nicotinic acetylcholine receptor (AChR) reconstituted in planar lipid bilayers were characterized. Single-channel currents were activated by acetylcholine, carbamylcholine and suberyldicholine. The single channel conductance (28 pS in 0.3 M NaCl...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(84)84145-4
更新日期:1984-01-01 00:00:00
abstract::Mössbauer spectra of anhydrohemoglobin establish the existence of two ferrous iron spin states in anhydrohemoglobin. Magnetic susceptibility measurements show that anhydrohemoglobin is paramagnetic and has an effective magnetic moment per iron atom of 3.5+/-0.1mu(B) at low temperatures. In conjunction with the suscept...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(67)86614-1
更新日期:1967-11-01 00:00:00
abstract::Five highly homologous epidermal growth factor receptor ligands were studied by mass spectral analysis, hydrogen/deuterium (H/D) exchange via attenuated total reflectance Fourier transform-infrared spectroscopy, and two-dimensional correlation analysis. These studies were performed to determine the order of events dur...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.125856
更新日期:2008-05-15 00:00:00
abstract::Cellular membranes are laterally organized into domains of distinct structures and compositions by the differential interaction affinities between various membrane lipids and proteins. A prominent example of such structures are lipid rafts, which are ordered, tightly packed domains that have been widely implicated in ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.03.020
更新日期:2018-04-24 00:00:00