TY - JOUR
T1 - K+ pore structure revealed by reporter cysteines at inner and outer surfaces
AU - Pascual, Juan M.
AU - Shieh, Char Chang
AU - Kirsch, Glenn E.
AU - Brown, Arthur M.
N1 - Funding Information:
We are grateful to Arthur Karlin for methanethiosulfonato samples and • advice. We thank Wei-Qiang Dong and Raynard Cockrell for technical assistance with oocyte injection and culture. We also acknowledge Alvaro Villarroel for the software and database used to generate endonuclease recognition sequences. This work was supported in part by National Institutes of Health grants NS23877 and HL37044 to A. M. B. and NS29473 to G. E. K.
PY - 1995/5
Y1 - 1995/5
N2 - The structure of the carboxyl half of the pore-forming region of Kv2.1 was studied by replacing each of 15 consecutive residues between positions 383 and 369 with a reporter cysteine residue. Extracellular application of charged, membrane-impermeant methanethiosulfonates irreversibly modified currents at four cysteine-substituted positions, K382, Y380,1379, and D378. Intracellular exposure to methanethiosulfonate ethyltrimethylammonium revealed another set of reactive mutants (V374, T373, T372, and T370). Our results indicate that positions 378 and 374 are exposed at outer and inner mouths of the channel, respectively, and immersed in the aqueous phase. In contrast to present topological models, the 383-369 region appears to span the pore mainly as a nonperiodic structure.
AB - The structure of the carboxyl half of the pore-forming region of Kv2.1 was studied by replacing each of 15 consecutive residues between positions 383 and 369 with a reporter cysteine residue. Extracellular application of charged, membrane-impermeant methanethiosulfonates irreversibly modified currents at four cysteine-substituted positions, K382, Y380,1379, and D378. Intracellular exposure to methanethiosulfonate ethyltrimethylammonium revealed another set of reactive mutants (V374, T373, T372, and T370). Our results indicate that positions 378 and 374 are exposed at outer and inner mouths of the channel, respectively, and immersed in the aqueous phase. In contrast to present topological models, the 383-369 region appears to span the pore mainly as a nonperiodic structure.
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U2 - 10.1016/0896-6273(95)90344-5
DO - 10.1016/0896-6273(95)90344-5
M3 - Article
C2 - 7748553
AN - SCOPUS:0029070117
SN - 0896-6273
VL - 14
SP - 1055
EP - 1063
JO - Neuron
JF - Neuron
IS - 5
ER -