Kcv from the chlorella virus PBCV-1 is a viral protein that forms a tetrameric, functional K+ channel in heterologous systems. Kcv can serve as a model system to study and manipulate basic properties of the K+ channel pore because its minimalistic structure (94 amino acids) produces basic features of ion channels, such as selectivity, gating, and sensitivity to blockers. We present a characterization of Kcv properties at the single-channel level. In symmetric 100 mM K+, single-channel conductance is 114 ± 11 pS. Two different voltage-dependent mechanisms are responsible for the gating of Kcv. “Fast” gating, analyzed by distributions, is responsible for the negative slope conductance in the single-channel current–voltage curve at extreme potentials, like in MaxiK potassium channels, and can be explained by depletion-aggravated instability of the filter region. The presence of a “slow” gating is revealed by the very low (in the order of 1–4%) mean open probability that is voltage dependent and underlies the time-dependent component of the macroscopic current.
|Titolo:||ANALYSIS OF INHERENT PROPERTIES OF ION CHANNELS FROM PBCV-1 CHLORELLA VIRUS AND INFLUENZA A VIRUS.|
|Data di pubblicazione:||13-gen-2011|
|Parole Chiave:||PBCV1-Kcv ; Chlorella virus|
|Settore Scientifico Disciplinare:||Settore BIO/04 - Fisiologia Vegetale|
|Citazione:||ANALYSIS OF INHERENT PROPERTIES OF ION CHANNELS FROM PBCV-1 CHLORELLA VIRUS AND INFLUENZA A VIRUS. ; tutor: Anna Moroni. - Milano : Università degli studi di Milano. DIPARTIMENTO DI BIOLOGIA, 2011 Jan 13. ((23. ciclo, Anno Accademico 2010.|
|Digital Object Identifier (DOI):||10.13130/di-francesco-mattia-lorenzo_phd2011-01-13|
|Appare nelle tipologie:||Tesi di dottorato|