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Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1)
Despite its importance as a health problem issue, almost nothing is known about the membrane physiology of Giardia lamblia and practically there exist no information so far regarding the variety and properties of ion channels that this protozoan parasite possesses. To address this subject we resorte...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Wiley Periodicals, Inc.
2013
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3970746/ https://www.ncbi.nlm.nih.gov/pubmed/24744864 http://dx.doi.org/10.1002/phy2.186 |
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author | Ponce, Arturo Jimenez‐Cardoso, Enedina Eligio‐Garcia, Leticia |
author_facet | Ponce, Arturo Jimenez‐Cardoso, Enedina Eligio‐Garcia, Leticia |
author_sort | Ponce, Arturo |
collection | PubMed |
description | Despite its importance as a health problem issue, almost nothing is known about the membrane physiology of Giardia lamblia and practically there exist no information so far regarding the variety and properties of ion channels that this protozoan parasite possesses. To address this subject we resorted to an indirect method, consisting in the injection of mRNA and further characterization of ion currents in Xenopus oocytes. In this work, we show that oocytes injected with mRNA isolated from cultured trophozoites of G. lamblia, strain Portland‐1 express novel potassium currents that appear over the second day after injection and show time‐ and voltage‐dependent activation followed by a slow inactivation. They start activating at −90 mV, with V(1/2) of −30 mV; its time constant of activation (at +60 mV) is 0.11 sec, whereas that of inactivation is 1.92 sec, V(1/2) = −44.6 mV. Such K currents were effectively blocked by K channel blockers TEA and 4AP, as well as Ba(2+), quinine, quinidine, charybdotoxin, dendrotoxin‐1, capsaicin, margatoxin, and diltiazem. These results suggest that such currents are the result of expression of Giardia′s voltage‐gated K channels heterologously expressed in Xenopus laevis oocytes. |
format | Online Article Text |
id | pubmed-3970746 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2013 |
publisher | Wiley Periodicals, Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-39707462014-03-31 Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) Ponce, Arturo Jimenez‐Cardoso, Enedina Eligio‐Garcia, Leticia Physiol Rep Original Research Despite its importance as a health problem issue, almost nothing is known about the membrane physiology of Giardia lamblia and practically there exist no information so far regarding the variety and properties of ion channels that this protozoan parasite possesses. To address this subject we resorted to an indirect method, consisting in the injection of mRNA and further characterization of ion currents in Xenopus oocytes. In this work, we show that oocytes injected with mRNA isolated from cultured trophozoites of G. lamblia, strain Portland‐1 express novel potassium currents that appear over the second day after injection and show time‐ and voltage‐dependent activation followed by a slow inactivation. They start activating at −90 mV, with V(1/2) of −30 mV; its time constant of activation (at +60 mV) is 0.11 sec, whereas that of inactivation is 1.92 sec, V(1/2) = −44.6 mV. Such K currents were effectively blocked by K channel blockers TEA and 4AP, as well as Ba(2+), quinine, quinidine, charybdotoxin, dendrotoxin‐1, capsaicin, margatoxin, and diltiazem. These results suggest that such currents are the result of expression of Giardia′s voltage‐gated K channels heterologously expressed in Xenopus laevis oocytes. Wiley Periodicals, Inc. 2013-12-29 /pmc/articles/PMC3970746/ /pubmed/24744864 http://dx.doi.org/10.1002/phy2.186 Text en © 2013 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society. This is an open access article under the terms of the Creative Commons Attribution (http://creativecommons.org/licenses/by/3.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Original Research Ponce, Arturo Jimenez‐Cardoso, Enedina Eligio‐Garcia, Leticia Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) |
title | Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) |
title_full | Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) |
title_fullStr | Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) |
title_full_unstemmed | Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) |
title_short | Voltage‐dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland‐1) |
title_sort | voltage‐dependent potassium currents expressed in xenopus laevis oocytes after injection of mrna isolated from trophozoites of giardia lamblia (strain portland‐1) |
topic | Original Research |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3970746/ https://www.ncbi.nlm.nih.gov/pubmed/24744864 http://dx.doi.org/10.1002/phy2.186 |
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