The aminoacid sequences of CNG and K+ channels share a significant sequence identity, and it has been suggested that these channels have a common ancestral 3D architecture. However, K+ and CNG channels have profoundly different physiological properties: indeed, K+ channels have a high ionic selectivity, their gating strongly depends on membrane voltage and when opened by a steady depolarizing voltage several K + channels inactivate, whereas CNG channels have a low ion selectivity, their gating is poorly voltage dependent, and they do not desensitize in the presence of a steady concentration of cyclic nucleotides that cause their opening. The purpose of the present review is to summarize and recapitulate functional and structural differences between K+ and CNG channels with the aim to understand the gating mechanisms of CNG channels.
Gating in CNGA1 channels / Mazzolini, M.; Marchesi, A.; Giorgetti, A.; Torre, V.. - In: PFLÜGERS ARCHIV. - ISSN 0031-6768. - 459:4(2010), pp. 547-555. [10.1007/s00424-009-0751-2]
Gating in CNGA1 channels
Marchesi A.;
2010-01-01
Abstract
The aminoacid sequences of CNG and K+ channels share a significant sequence identity, and it has been suggested that these channels have a common ancestral 3D architecture. However, K+ and CNG channels have profoundly different physiological properties: indeed, K+ channels have a high ionic selectivity, their gating strongly depends on membrane voltage and when opened by a steady depolarizing voltage several K + channels inactivate, whereas CNG channels have a low ion selectivity, their gating is poorly voltage dependent, and they do not desensitize in the presence of a steady concentration of cyclic nucleotides that cause their opening. The purpose of the present review is to summarize and recapitulate functional and structural differences between K+ and CNG channels with the aim to understand the gating mechanisms of CNG channels.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
