ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Membrane biology Permutations of permeability (2006)
    [s.l.] : Nature Publishing Group
    Nature 440 (2006), S. 427-429 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Ion channels are nature's gatekeepers: by allowing certain ions to pass across the membrane and excluding others, these proteins control the electrical state of the cell. Channels selective for sodium ions allow Na+ to enter the cell, causing depolarization of the membrane. In ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/440427a
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Structural basis for modulation and agonist specificity of HCN pacemaker channels (2003)
    [s.l.] : Macmillian Magazines Ltd.
    Nature 425 (2003), S. 200-205 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The family of hyperpolarization-activated, cyclic nucleotide-modulated (HCN) channels are crucial for a range of electrical signalling, including cardiac and neuronal pacemaker activity, setting resting membrane electrical properties and dendritic integration. These nonselective cation ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/nature01922
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Rotational movement during cyclic nucleotide-gated channel opening (2001)
    [s.l.] : Macmillian Magazines Ltd.
    Nature 412 (2001), S. 917-921 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Cyclic nucleotide-gated (CNG) channels are crucial components of visual, olfactory and gustatory signalling pathways. They open in response to direct binding of intracellular cyclic nucleotides and thus contribute to cellular control of both the membrane potential and intracellular ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/35091089
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    CNG AND HCN CHANNELS: Two Peas, One Pod (2006)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Physiology 68 (2006), S. 375-401 
    Details
    ISSN: 0066-4278
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Medicine , Biology
    Notes: Cyclic nucleotideĐ??activated ion channels play a fundamental role in a variety of physiological processes. By opening in response to intracellular cyclic nucleotides, they translate changes in concentrations of signaling molecules to changes in membrane potential. These channels belong to two families: the cyclic nucleotideĐ??gated (CNG) channels and the hyperpolarization-activated cyclic nucleotideĐ??modulated (HCN) channels. The two families exhibit high sequence similarity and belong to the superfamily of voltage-gated potassium channels. Whereas HCN channels are activated by voltage and CNG channels are virtually voltage independent, both channels are activated by cyclic nucleotide binding. Furthermore, the channels are thought to have similar channel structures, leading to similar mechanisms of activation by cyclic nucleotides. However, although these channels are structurally and behaviorally similar, they have evolved to perform distinct physiological functions. This review describes the physiological roles and biophysical behavior of CNG and HCN channels. We focus on how similarities in structure and activation mechanisms result in common biophysical models, allowing CNG and HCN channels to be viewed as a single genre.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.physiol.68.040104.134728
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Structural dynamics in the gating ring of cyclic nucleotide–gated ion channels (2007)
    [s.l.] : Nature Publishing Group
    Nature structural & molecular biology 14 (2007), S. 854-860 
    Details
    ISSN: 1545-9985
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Medicine
    Notes: [Auszug] For ligand-gated ion channels, the binding of a ligand to an intracellular or extracellular domain generates changes in transmembrane pore-forming helices, which alters ion flow. The molecular mechanism for this allostery, however, remains unknown. Here we explore the structure and conformational ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/nsmb1281
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Molecular mechanisms of cyclic nucleotide-gated channels (1996)
    Springer
    Journal of bioenergetics and biomembranes 28 (1996), S. 269-278 
    Details
    ISSN: 1573-6881
    Keywords: Phototransduction ; olfaction ; ion channels ; cGMP ; cAMP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Physics
    Notes: Abstract Cyclic nucleotide-gated (CNG) channels are highly specialized to carry out their unique role in cell signaling. Significant progress has been made in the last several years determining the molecular mechanisms for these specializations. The activation of the channels begins with the binding of cyclic nucleotide to a domain in the carboxyl terminal region. This binding, in turn, produces an induced fit of the protein that involves a movement of the C-helix portion of the binding domain. The induced fit of the binding domain is coupled to an allosteric conformational change that opens the channel pore. The pore is formed primarily from the sequence between the S5 and S6 segments. A single glutamic acid in the pore represents the binding site for multiple monovalent cations, the blocking site for external divalent cations, and the site for the effect of protons on permeation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02110700
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Sarcomere length behaviour along single frog muscle fibres at different lengths during isometric tetani (1989)
    Springer
    Journal of muscle research and cell motility 10 (1989), S. 67-84 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A detailed investigation of sarcomere lengthening and shortening during fixed-end tetani has been made along frog muscle fibres stretched over a large range of sarcomere lengths. A variety of sources of error common in such measurements are quantitated and give an uncertainty in sarcomere length of about 53–62 nm. The difference in sarcomere length calculated from the left and right first orders at rest was 21 nm ±16 nm and this is suggested to be a measure of ‘Bragg artefact’. The laser diffraction measurements showed that the shortening end regions decrease in size during contraction and that the magnitude of shortening is increased at greater fibre extensions. The average length change and sarcomere length of the central and end regions was 0.10 μm (2.85 μm) and −0.37 μm (2.66 μm), respectively. The sarcomere length of the end regions at the end of creep was regularly observed to be 〈2.1 μm. An unexpected finding was the occasional observation of striations in the transition zone between lengthening and shortening regions which remained nearly isometric during a period of tension rise during creep. Measurements of diffraction order linewidth do not suggest increased sarcomere length dispersion in these areas. A smooth transition from shortening to lengthening was always observed. Although our data are in general agreement with the models proposed by Morgan, Mochon and Julian (Biophys. J. 39 (1982) 189–96) and Edman and Reggiani(J. Physiol. (Lond.) 351 (1984) 169–98), specific differences which do exist are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01739857
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    facet.materialart.
    Unknown
    Insights into the molecular mechanism for hyperpolarization-dependent activation of HCN channels (2018)
    National Academy of Sciences
    Details
    Publication Date: 2018-08-03
    Description: Hyperpolarization-activated, cyclic nucleotide-gated (HCN) ion channels are both voltage- and ligand-activated membrane proteins that contribute to electrical excitability and pace-making activity in cardiac and neuronal cells. These channels are members of the voltage-gated Kv channel superfamily and cyclic nucleotide-binding domain subfamily of ion channels. HCN channels have a unique feature that distinguishes them from other voltage-gated channels: the HCN channel pore opens in response to hyperpolarizing voltages instead of depolarizing voltages. In the canonical model of electromechanical coupling, based on Kv channels, a change in membrane voltage activates the voltage-sensing domains (VSD) and the activation energy passes to the pore domain (PD) through a covalent linker that connects the VSD to the PD. In this investigation, the covalent linkage between the VSD and PD, the S4-S5 linker, and nearby regions of spHCN channels were mutated to determine the functional role each plays in hyperpolarization-dependent activation. The results show that: (i) the S4-S5 linker is not required for hyperpolarization-dependent activation or ligand-dependent gating; (ii) the S4 C-terminal region (S4C-term) is not necessary for ligand-dependent gating but is required for hyperpolarization-dependent activation and acts like an autoinhibitory domain on the PD; (iii) the S5N-term region is involved in VSD–PD coupling and holding the pore closed; and (iv) spHCN channels have two voltage-dependent processes, a hyperpolarization-dependent activation and a depolarization-dependent recovery from inactivation. These results are inconsistent with the canonical model of VSD–PD coupling in Kv channels and elucidate the mechanism for hyperpolarization-dependent activation of HCN channels.
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    Double electron–electron resonance reveals cAMP-induced conformational change in HCN channels (2014)
    National Academy of Sciences
    Details
    Publication Date: 2014-06-23
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Allosteric conformational change of a cyclic nucleotide-gated ion channel revealed by DEER spectroscopy (2020)
    National Academy of Sciences
    Details
    Publication Date: 2020-05-01
    Description: Cyclic nucleotide-gated (CNG) ion channels are essential components of mammalian visual and olfactory signal transduction. CNG channels open upon direct binding of cyclic nucleotides (cAMP and/or cGMP), but the allosteric mechanism by which this occurs is incompletely understood. Here, we employed double electron-electron resonance (DEER) spectroscopy to measure intersubunit distance distributions in SthK, a bacterial CNG channel from Spirochaeta thermophila. Spin labels were introduced into the SthK C-linker, a domain that is essential for coupling cyclic nucleotide binding to channel opening. DEER revealed an agonist-dependent conformational change in which residues of the B′-helix displayed outward movement with respect to the symmetry axis of the channel in the presence of the full agonist cAMP, but not with the partial agonist cGMP. This conformational rearrangement was observed both in detergent-solubilized SthK and in channels reconstituted into lipid nanodiscs. In addition to outward movement of the B′-helix, DEER-constrained Rosetta structural models suggest that channel activation involves upward translation of the cytoplasmic domain and formation of state-dependent interactions between the C-linker and the transmembrane domain. Our results demonstrate a previously unrecognized structural transition in a CNG channel and suggest key interactions that may be responsible for allosteric gating in these channels.
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...