Is the mammalian porin channel, VDAC, a perfect cylinder in the high conductance state?

FEBS Letters

Krasilnikov, O.V¹  Yuldasheva, L.N²  Nogueira, R.A²  Campos de Carvalho, A.C³  Carneiro, C.M.M² 

[1] Laboratory of Molecular Physiology, Institute of Physiology and Biophysics, 700095 Tashkent, Uzbekistan;Laboratory of Membrane Biophysics, Center of Biological Sciences, Department of Biophysics and Radiobiology, Federal University of Pernambuco, Av. prof. Moraes Rego, s/n, Cidade Universitaria, 50670-901 Recife, PE, Brazil;Institute of Biophysics Carlos Chagas Filho, UFRJ, Rio de Janeiro, RJ, Brazil

关键词: Voltage-dependent anion-selective channel;    Ion channel;    Size;   

DOI  :  10.1016/S0014-5793(97)01198-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The mammalian porin channel (VDAC, porin-31BM) was reconstituted in planar lipid bilayers under voltage clamp conditions. The radii of both entrances of the channel were examined using a method that consisted in filling the channel with different non-electrolytes through its cis or trans entrances while recording single channel conductances. As a result it was found that the geometry of channels formed by porin-31BM could not be approximated by a perfectly cylindrical pore. In fact there is an asymmetry in the geometry of the channel: the diameters of the cis and trans entrances were estimated to be ∼2 nm and ∼4 nm respectively.

【 授权许可】

Unknown