scholarly journals Cytoplasmic Domains and Voltage-Dependent Potassium Channel Gating

2012 ◽  
Vol 3 ◽  
Author(s):  
Francisco Barros ◽  
Pedro Domínguez ◽  
Pilar de la Peña
Keyword(s):  
Potassium Channel ◽  
Channel Gating ◽  
Cytoplasmic Domains ◽  
Voltage Dependent ◽  
Potassium Channel Gating

scholarly journals Control of KirBac3.1 Potassium Channel Gating at the Interface between Cytoplasmic Domains

2013 ◽  
Vol 289 (1) ◽  
pp. 143-151 ◽  
Author(s):  
Lejla Zubcevic ◽  
Vassiliy N. Bavro ◽  
Joao R. C. Muniz ◽  
Matthias R. Schmidt ◽  
Shizhen Wang ◽  
...  
Keyword(s):  
Potassium Channel ◽  
Channel Gating ◽  
Cytoplasmic Domains ◽  
Potassium Channel Gating

Direct Visualization of KirBac3.1 Potassium Channel Gating by Atomic Force Microscopy

2007 ◽  
Vol 374 (2) ◽  
pp. 500-505 ◽  
Author(s):  
Szymon Jarosławski ◽  
Brittany Zadek ◽  
Frances Ashcroft ◽  
Catherine Vénien-Bryan ◽  
Simon Scheuring
Keyword(s):  
Atomic Force Microscopy ◽  
Potassium Channel ◽  
Channel Gating ◽  
Direct Visualization ◽  
Force Microscopy ◽  
Atomic Force ◽  
Potassium Channel Gating

scholarly journals Radiolytic Footprinting Reveals Conformational Changes During Potassium Channel Gating

2010 ◽  
Vol 98 (3) ◽  
pp. 696a
Author(s):  
Sayan Gupta ◽  
Rhijuta D'Mello ◽  
Mark R. Chance ◽  
Vassiliy N. Bavro ◽  
Catherine Venien-Bryan ◽  
...  
Keyword(s):  
Potassium Channel ◽  
Conformational Changes ◽  
Channel Gating ◽  
Potassium Channel Gating

scholarly journals Structural Basis of a Kv7.1 Potassium Channel Gating Module: Studies of the Intracellular C-Terminal Domain in Complex with Calmodulin

Structure ◽  
2014 ◽  
Vol 22 (11) ◽  
pp. 1582-1594 ◽  
Author(s):  
Dana Sachyani ◽  
Meidan Dvir ◽  
Roi Strulovich ◽  
Giancarlo Tria ◽  
William Tobelaim ◽  
...  
Keyword(s):  
Potassium Channel ◽  
Channel Gating ◽  
Structural Basis ◽  
Terminal Domain ◽  
Potassium Channel Gating

scholarly journals Uncharged S4 Residues and Cooperativity in Voltage-dependent Potassium Channel Activation

1998 ◽  
Vol 111 (3) ◽  
pp. 421-439 ◽  
Author(s):  
Catherine J. Smith-Maxwell ◽  
Jennifer L. Ledwell ◽  
Richard W. Aldrich
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Potassium Channel ◽  
Voltage Dependence ◽  
Channel Gating ◽  
Ionic Currents ◽  
Channel Activation ◽  
Functional Changes ◽  
Activation Pathway ◽  
Voltage Dependent

Substitution of the S4 of Shaw into Shaker alters cooperativity in channel activation by slowing a cooperative transition late in the activation pathway. To determine the amino acids responsible for the functional changes in Shaw S4, we created several mutants by substituting amino acids from Shaw S4 into Shaker. The S4 amino acid sequences of Shaker and Shaw S4 differ at 11 positions. Simultaneous substitution of just three noncharged residues from Shaw S4 into Shaker (V369I, I372L, S376T; ILT) reproduces the kinetic and voltage-dependent properties of Shaw S4 channel activation. These substitutions cause very small changes in the structural and chemical properties of the amino acid side chains. In contrast, substituting the positively charged basic residues in the S4 of Shaker with neutral or negative residues from the S4 of Shaw S4 does not reproduce the shallow voltage dependence or other properties of Shaw S4 opening. Macroscopic ionic currents for ILT could be fit by modifying a single set of transitions in a model for Shaker channel gating (Zagotta, W.N., T. Hoshi, and R.W. Aldrich. 1994. J. Gen. Physiol. 103:321–362). Changing the rate and voltage dependence of a final cooperative step in activation successfully reproduces the kinetic, steady state, and voltage-dependent properties of ILT ionic currents. Consistent with the model, ILT gating currents activate at negative voltages where the channel does not open and, at more positive voltages, they precede the ionic currents, confirming the existence of voltage-dependent transitions between closed states in the activation pathway. Of the three substitutions in ILT, the I372L substitution is primarily responsible for the changes in cooperativity and voltage dependence. These results suggest that noncharged residues in the S4 play a crucial role in Shaker potassium channel gating and that small steric changes in these residues can lead to large changes in cooperativity within the channel protein.

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