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. 1993 Apr 1;101(4):513–543. doi: 10.1085/jgp.101.4.513

A rapidly activating and slowly inactivating potassium channel cloned from human heart. Functional analysis after stable mammalian cell culture expression

PMCID: PMC2216772  PMID: 8505626

Abstract

The electrophysiological properties of HK2 (Kv1.5), a K+ channel cloned from human ventricle, were investigated after stable expression in a mouse Ltk- cell line. Cell lines that expressed HK2 mRNA displayed a current with delayed rectifier properties at 23 degrees C, while sham transfected cell lines showed neither specific HK2 mRNA hybridization nor voltage-activated currents under whole cell conditions. The expression of the HK2 current has been stable for over two years. The dependence of the reversal potential of this current on the external K+ concentration (55 mV/decade) confirmed K+ selectivity, and the tail envelope test was satisfied, indicating expression of a single population of K+ channels. The activation time course was fast and sigmoidal (time constants declined from 10 ms to < 2 ms between 0 and +60 mV). The midpoint and slope factor of the activation curve were Eh = -14 +/- 5 mV and k = 5.9 +/- 0.9 (n = 31), respectively. Slow partial inactivation was observed especially at large depolarizations (20 +/- 2% after 250 ms at +60 mV, n = 32), and was incomplete in 5 s (69 +/- 3%, n = 14). This slow inactivation appeared to be a genuine gating process and not due to K+ accumulation, because it was present regardless of the size of the current and was observed even with 140 mM external K+ concentration. Slow inactivation had a biexponential time course with largely voltage-independent time constants of approximately 240 and 2,700 ms between -10 and +60 mV. The voltage dependence of slow inactivation overlapped with that of activation: Eh = -25 +/- 4 mV and k = 3.7 +/- 0.7 (n = 14). The fully activated current-voltage relationship displayed outward rectification in 4 mM external K+ concentration, but was more linear at higher external K+ concentrations, changes that could be explained in part on the basis of constant field (Goldman-Hodgkin-Katz) rectification. Activation and inactivation kinetics displayed a marked temperature dependence, resulting in faster activation and enhanced inactivation at higher temperature. The current was sensitive to low concentrations of 4- aminopyridine, but relatively insensitive to external TEA and to high concentrations of dendrotoxin. The expressed current did not resemble either the rapid or the slow components of delayed rectification described in guinea pig myocytes. However, this channel has many similarities to the rapidly activating delayed rectifying currents described in adult rat atrial and neonatal canine epicardial myocytes.(ABSTRACT TRUNCATED AT 400 WORDS)

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Selected References

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  1. Agus Z. S., Dukes I. D., Morad M. Divalent cations modulate the transient outward current in rat ventricular myocytes. Am J Physiol. 1991 Aug;261(2 Pt 1):C310–C318. doi: 10.1152/ajpcell.1991.261.2.C310. [DOI] [PubMed] [Google Scholar]
  2. Arena J. P., Kass R. S. Block of heart potassium channels by clofilium and its tertiary analogs: relationship between drug structure and type of channel blocked. Mol Pharmacol. 1988 Jul;34(1):60–66. [PubMed] [Google Scholar]
  3. Armstrong C. M. Interaction of tetraethylammonium ion derivatives with the potassium channels of giant axons. J Gen Physiol. 1971 Oct;58(4):413–437. doi: 10.1085/jgp.58.4.413. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Balser J. R., Bennett P. B., Roden D. M. Time-dependent outward current in guinea pig ventricular myocytes. Gating kinetics of the delayed rectifier. J Gen Physiol. 1990 Oct;96(4):835–863. doi: 10.1085/jgp.96.4.835. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Benishin C. G., Sorensen R. G., Brown W. E., Krueger B. K., Blaustein M. P. Four polypeptide components of green mamba venom selectively block certain potassium channels in rat brain synaptosomes. Mol Pharmacol. 1988 Aug;34(2):152–159. [PubMed] [Google Scholar]
  6. Bezanilla F., Perozo E., Papazian D. M., Stefani E. Molecular basis of gating charge immobilization in Shaker potassium channels. Science. 1991 Nov 1;254(5032):679–683. doi: 10.1126/science.1948047. [DOI] [PubMed] [Google Scholar]
  7. Boyle W. A., Nerbonne J. M. A novel type of depolarization-activated K+ current in isolated adult rat atrial myocytes. Am J Physiol. 1991 Apr;260(4 Pt 2):H1236–H1247. doi: 10.1152/ajpheart.1991.260.4.H1236. [DOI] [PubMed] [Google Scholar]
  8. Boyle W. A., Nerbonne J. M. Two functionally distinct 4-aminopyridine-sensitive outward K+ currents in rat atrial myocytes. J Gen Physiol. 1992 Dec;100(6):1041–1067. doi: 10.1085/jgp.100.6.1041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Campbell D. L., Qu Y., Rasmusson R. L., Strauss H. C. The calcium-independent transient outward potassium current in isolated ferret right ventricular myocytes. II. Closed state reverse use-dependent block by 4-aminopyridine. J Gen Physiol. 1993 Apr;101(4):603–626. doi: 10.1085/jgp.101.4.603. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Chandy K. G. Simplified gene nomenclature. Nature. 1991 Jul 4;352(6330):26–26. doi: 10.1038/352026b0. [DOI] [PubMed] [Google Scholar]
  11. Choi K. L., Aldrich R. W., Yellen G. Tetraethylammonium blockade distinguishes two inactivation mechanisms in voltage-activated K+ channels. Proc Natl Acad Sci U S A. 1991 Jun 15;88(12):5092–5095. doi: 10.1073/pnas.88.12.5092. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Chung F. Z., Wang C. D., Potter P. C., Venter J. C., Fraser C. M. Site-directed mutagenesis and continuous expression of human beta-adrenergic receptors. Identification of a conserved aspartate residue involved in agonist binding and receptor activation. J Biol Chem. 1988 Mar 25;263(9):4052–4055. [PubMed] [Google Scholar]
  13. Demo S. D., Yellen G. The inactivation gate of the Shaker K+ channel behaves like an open-channel blocker. Neuron. 1991 Nov;7(5):743–753. doi: 10.1016/0896-6273(91)90277-7. [DOI] [PubMed] [Google Scholar]
  14. Escande D., Coulombe A., Faivre J. F., Deroubaix E., Coraboeuf E. Two types of transient outward currents in adult human atrial cells. Am J Physiol. 1987 Jan;252(1 Pt 2):H142–H148. doi: 10.1152/ajpheart.1987.252.1.H142. [DOI] [PubMed] [Google Scholar]
  15. Fan Z., Hiraoka M. Depression of delayed outward K+ current by Co2+ in guinea pig ventricular myocytes. Am J Physiol. 1991 Jul;261(1 Pt 1):C23–C31. doi: 10.1152/ajpcell.1991.261.1.C23. [DOI] [PubMed] [Google Scholar]
  16. Folander K., Smith J. S., Antanavage J., Bennett C., Stein R. B., Swanson R. Cloning and expression of the delayed-rectifier IsK channel from neonatal rat heart and diethylstilbestrol-primed rat uterus. Proc Natl Acad Sci U S A. 1990 Apr;87(8):2975–2979. doi: 10.1073/pnas.87.8.2975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Follmer C. H., Lodge N. J., Cullinan C. A., Colatsky T. J. Modulation of the delayed rectifier, IK, by cadmium in cat ventricular myocytes. Am J Physiol. 1992 Jan;262(1 Pt 1):C75–C83. doi: 10.1152/ajpcell.1992.262.1.C75. [DOI] [PubMed] [Google Scholar]
  18. Frace A. M., Gargus J. J. Activation of single-channel currents in mouse fibroblasts by platelet-derived growth factor. Proc Natl Acad Sci U S A. 1989 Apr;86(7):2511–2515. doi: 10.1073/pnas.86.7.2511. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. HODGKIN A. L., HUXLEY A. F. A quantitative description of membrane current and its application to conduction and excitation in nerve. J Physiol. 1952 Aug;117(4):500–544. doi: 10.1113/jphysiol.1952.sp004764. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. HODGKIN A. L., KATZ B. The effect of sodium ions on the electrical activity of giant axon of the squid. J Physiol. 1949 Mar 1;108(1):37–77. doi: 10.1113/jphysiol.1949.sp004310. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
  22. Heidbüchel H., Vereecke J., Carmeliet E. Three different potassium channels in human atrium. Contribution to the basal potassium conductance. Circ Res. 1990 May;66(5):1277–1286. doi: 10.1161/01.res.66.5.1277. [DOI] [PubMed] [Google Scholar]
  23. Hoshi T., Zagotta W. N., Aldrich R. W. Biophysical and molecular mechanisms of Shaker potassium channel inactivation. Science. 1990 Oct 26;250(4980):533–538. doi: 10.1126/science.2122519. [DOI] [PubMed] [Google Scholar]
  24. Hoshi T., Zagotta W. N., Aldrich R. W. Two types of inactivation in Shaker K+ channels: effects of alterations in the carboxy-terminal region. Neuron. 1991 Oct;7(4):547–556. doi: 10.1016/0896-6273(91)90367-9. [DOI] [PubMed] [Google Scholar]
  25. Hosoi S., Slayman C. L. Membrane voltage, resistance, and channel switching in isolated mouse fibroblasts (L cells): a patch-electrode analysis. J Physiol. 1985 Oct;367:267–290. doi: 10.1113/jphysiol.1985.sp015824. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Hurst R. S., Busch A. E., Kavanaugh M. P., Osborne P. B., North R. A., Adelman J. P. Identification of amino acid residues involved in dendrotoxin block of rat voltage-dependent potassium channels. Mol Pharmacol. 1991 Oct;40(4):572–576. [PubMed] [Google Scholar]
  27. Imoto K., Busch C., Sakmann B., Mishina M., Konno T., Nakai J., Bujo H., Mori Y., Fukuda K., Numa S. Rings of negatively charged amino acids determine the acetylcholine receptor channel conductance. Nature. 1988 Oct 13;335(6191):645–648. doi: 10.1038/335645a0. [DOI] [PubMed] [Google Scholar]
  28. Isacoff E. Y., Jan Y. N., Jan L. Y. Putative receptor for the cytoplasmic inactivation gate in the Shaker K+ channel. Nature. 1991 Sep 5;353(6339):86–90. doi: 10.1038/353086a0. [DOI] [PubMed] [Google Scholar]
  29. Iverson L. E., Rudy B. The role of the divergent amino and carboxyl domains on the inactivation properties of potassium channels derived from the Shaker gene of Drosophila. J Neurosci. 1990 Sep;10(9):2903–2916. doi: 10.1523/JNEUROSCI.10-09-02903.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Jeck C. D., Boyden P. A. Age-related appearance of outward currents may contribute to developmental differences in ventricular repolarization. Circ Res. 1992 Dec;71(6):1390–1403. doi: 10.1161/01.res.71.6.1390. [DOI] [PubMed] [Google Scholar]
  31. Kass R. S., Scheuer T., Malloy K. J. Block of outward current in cardiac Purkinje fibers by injection of quaternary ammonium ions. J Gen Physiol. 1982 Jun;79(6):1041–1063. doi: 10.1085/jgp.79.6.1041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Kavanaugh M. P., Varnum M. D., Osborne P. B., Christie M. J., Busch A. E., Adelman J. P., North R. A. Interaction between tetraethylammonium and amino acid residues in the pore of cloned voltage-dependent potassium channels. J Biol Chem. 1991 Apr 25;266(12):7583–7587. [PubMed] [Google Scholar]
  33. Kenyon J. L., Gibbons W. R. 4-Aminopyridine and the early outward current of sheep cardiac Purkinje fibers. J Gen Physiol. 1979 Feb;73(2):139–157. doi: 10.1085/jgp.73.2.139. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Koren G., Liman E. R., Logothetis D. E., Nadal-Ginard B., Hess P. Gating mechanism of a cloned potassium channel expressed in frog oocytes and mammalian cells. Neuron. 1990 Jan;4(1):39–51. doi: 10.1016/0896-6273(90)90442-i. [DOI] [PubMed] [Google Scholar]
  35. Liman E. R., Tytgat J., Hess P. Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs. Neuron. 1992 Nov;9(5):861–871. doi: 10.1016/0896-6273(92)90239-a. [DOI] [PubMed] [Google Scholar]
  36. Liman E. R., Tytgat J., Hess P. Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs. Neuron. 1992 Nov;9(5):861–871. doi: 10.1016/0896-6273(92)90239-a. [DOI] [PubMed] [Google Scholar]
  37. MacKinnon R. Determination of the subunit stoichiometry of a voltage-activated potassium channel. Nature. 1991 Mar 21;350(6315):232–235. doi: 10.1038/350232a0. [DOI] [PubMed] [Google Scholar]
  38. MacKinnon R., Yellen G. Mutations affecting TEA blockade and ion permeation in voltage-activated K+ channels. Science. 1990 Oct 12;250(4978):276–279. doi: 10.1126/science.2218530. [DOI] [PubMed] [Google Scholar]
  39. Matsuura H., Ehara T., Imoto Y. An analysis of the delayed outward current in single ventricular cells of the guinea-pig. Pflugers Arch. 1987 Dec;410(6):596–603. doi: 10.1007/BF00581319. [DOI] [PubMed] [Google Scholar]
  40. Murai T., Kakizuka A., Takumi T., Ohkubo H., Nakanishi S. Molecular cloning and sequence analysis of human genomic DNA encoding a novel membrane protein which exhibits a slowly activating potassium channel activity. Biochem Biophys Res Commun. 1989 May 30;161(1):176–181. doi: 10.1016/0006-291x(89)91577-5. [DOI] [PubMed] [Google Scholar]
  41. Okada Y., Yada T., Ohno-Shosaku T., Oiki S. Evidence for the involvement of calmodulin in the operation of Ca-activated K channels in mouse fibroblasts. J Membr Biol. 1987;96(2):121–128. doi: 10.1007/BF01869238. [DOI] [PubMed] [Google Scholar]
  42. Papazian D. M., Schwarz T. L., Tempel B. L., Jan Y. N., Jan L. Y. Cloning of genomic and complementary DNA from Shaker, a putative potassium channel gene from Drosophila. Science. 1987 Aug 14;237(4816):749–753. doi: 10.1126/science.2441470. [DOI] [PubMed] [Google Scholar]
  43. Paulmichl M., Nasmith P., Hellmiss R., Reed K., Boyle W. A., Nerbonne J. M., Peralta E. G., Clapham D. E. Cloning and expression of a rat cardiac delayed rectifier potassium channel. Proc Natl Acad Sci U S A. 1991 Sep 1;88(17):7892–7895. doi: 10.1073/pnas.88.17.7892. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Perez-Reyes E., Kim H. S., Lacerda A. E., Horne W., Wei X. Y., Rampe D., Campbell K. P., Brown A. M., Birnbaumer L. Induction of calcium currents by the expression of the alpha 1-subunit of the dihydropyridine receptor from skeletal muscle. Nature. 1989 Jul 20;340(6230):233–236. doi: 10.1038/340233a0. [DOI] [PubMed] [Google Scholar]
  45. Pfaff S. L., Tamkun M. M., Taylor W. L. pOEV: a Xenopus oocyte protein expression vector. Anal Biochem. 1990 Jul;188(1):192–199. doi: 10.1016/0003-2697(90)90551-j. [DOI] [PubMed] [Google Scholar]
  46. Philipson L. H., Hice R. E., Schaefer K., LaMendola J., Bell G. I., Nelson D. J., Steiner D. F. Sequence and functional expression in Xenopus oocytes of a human insulinoma and islet potassium channel. Proc Natl Acad Sci U S A. 1991 Jan 1;88(1):53–57. doi: 10.1073/pnas.88.1.53. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Roberds S. L., Tamkun M. M. Cloning and tissue-specific expression of five voltage-gated potassium channel cDNAs expressed in rat heart. Proc Natl Acad Sci U S A. 1991 Mar 1;88(5):1798–1802. doi: 10.1073/pnas.88.5.1798. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Roberds S. L., Tamkun M. M. Developmental expression of cloned cardiac potassium channels. FEBS Lett. 1991 Jun 24;284(2):152–154. doi: 10.1016/0014-5793(91)80673-q. [DOI] [PubMed] [Google Scholar]
  49. Ruppersberg J. P., Frank R., Pongs O., Stocker M. Cloned neuronal IK(A) channels reopen during recovery from inactivation. Nature. 1991 Oct 17;353(6345):657–660. doi: 10.1038/353657a0. [DOI] [PubMed] [Google Scholar]
  50. Sanguinetti M. C., Jurkiewicz N. K. Lanthanum blocks a specific component of IK and screens membrane surface change in cardiac cells. Am J Physiol. 1990 Dec;259(6 Pt 2):H1881–H1889. doi: 10.1152/ajpheart.1990.259.6.H1881. [DOI] [PubMed] [Google Scholar]
  51. Sanguinetti M. C., Jurkiewicz N. K. Two components of cardiac delayed rectifier K+ current. Differential sensitivity to block by class III antiarrhythmic agents. J Gen Physiol. 1990 Jul;96(1):195–215. doi: 10.1085/jgp.96.1.195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Shibata E. F., Drury T., Refsum H., Aldrete V., Giles W. Contributions of a transient outward current to repolarization in human atrium. Am J Physiol. 1989 Dec;257(6 Pt 2):H1773–H1781. doi: 10.1152/ajpheart.1989.257.6.H1773. [DOI] [PubMed] [Google Scholar]
  53. Snyders D. J., Hondeghem L. M. Effects of quinidine on the sodium current of guinea pig ventricular myocytes. Evidence for a drug-associated rested state with altered kinetics. Circ Res. 1990 Feb;66(2):565–579. doi: 10.1161/01.res.66.2.565. [DOI] [PubMed] [Google Scholar]
  54. Spires S., Begenisich T. Pharmacological and kinetic analysis of K channel gating currents. J Gen Physiol. 1989 Feb;93(2):263–283. doi: 10.1085/jgp.93.2.263. [DOI] [PMC free article] [PubMed] [Google Scholar]
  55. Stühmer W., Stocker M., Sakmann B., Seeburg P., Baumann A., Grupe A., Pongs O. Potassium channels expressed from rat brain cDNA have delayed rectifier properties. FEBS Lett. 1988 Dec 19;242(1):199–206. doi: 10.1016/0014-5793(88)81015-9. [DOI] [PubMed] [Google Scholar]
  56. Swanson R., Marshall J., Smith J. S., Williams J. B., Boyle M. B., Folander K., Luneau C. J., Antanavage J., Oliva C., Buhrow S. A. Cloning and expression of cDNA and genomic clones encoding three delayed rectifier potassium channels in rat brain. Neuron. 1990 Jun;4(6):929–939. doi: 10.1016/0896-6273(90)90146-7. [DOI] [PubMed] [Google Scholar]
  57. Takeyasu K., Tamkun M. M., Siegel N. R., Fambrough D. M. Expression of hybrid (Na+ + K+)-ATPase molecules after transfection of mouse Ltk-cells with DNA encoding the beta-subunit of an avian brain sodium pump. J Biol Chem. 1987 Aug 5;262(22):10733–10740. [PubMed] [Google Scholar]
  58. Takumi T., Ohkubo H., Nakanishi S. Cloning of a membrane protein that induces a slow voltage-gated potassium current. Science. 1988 Nov 18;242(4881):1042–1045. doi: 10.1126/science.3194754. [DOI] [PubMed] [Google Scholar]
  59. Tamkun M. M., Knoth K. M., Walbridge J. A., Kroemer H., Roden D. M., Glover D. M. Molecular cloning and characterization of two voltage-gated K+ channel cDNAs from human ventricle. FASEB J. 1991 Mar 1;5(3):331–337. doi: 10.1096/fasebj.5.3.2001794. [DOI] [PubMed] [Google Scholar]
  60. Thornhill W. B., Levinson S. R. Biosynthesis of electroplax sodium channels in Electrophorus electrocytes and Xenopus oocytes. Biochemistry. 1987 Jul 14;26(14):4381–4388. doi: 10.1021/bi00388a029. [DOI] [PubMed] [Google Scholar]
  61. Tseng-Crank J. C., Tseng G. N., Schwartz A., Tanouye M. A. Molecular cloning and functional expression of a potassium channel cDNA isolated from a rat cardiac library. FEBS Lett. 1990 Jul 30;268(1):63–68. doi: 10.1016/0014-5793(90)80973-m. [DOI] [PubMed] [Google Scholar]
  62. Ukomadu C., Zhou J., Sigworth F. J., Agnew W. S. muI Na+ channels expressed transiently in human embryonic kidney cells: biochemical and biophysical properties. Neuron. 1992 Apr;8(4):663–676. doi: 10.1016/0896-6273(92)90088-u. [DOI] [PubMed] [Google Scholar]
  63. Van Bogaert P. P., Snyders D. J. Effects of 4-aminopyridine on inward rectifying and pacemaker currents of cardiac Purkinje fibres. Pflugers Arch. 1982 Sep;394(3):230–238. doi: 10.1007/BF00589097. [DOI] [PubMed] [Google Scholar]
  64. VanDongen A. M., Frech G. C., Drewe J. A., Joho R. H., Brown A. M. Alteration and restoration of K+ channel function by deletions at the N- and C-termini. Neuron. 1990 Oct;5(4):433–443. doi: 10.1016/0896-6273(90)90082-q. [DOI] [PubMed] [Google Scholar]
  65. Varadi G., Lory P., Schultz D., Varadi M., Schwartz A. Acceleration of activation and inactivation by the beta subunit of the skeletal muscle calcium channel. Nature. 1991 Jul 11;352(6331):159–162. doi: 10.1038/352159a0. [DOI] [PubMed] [Google Scholar]
  66. White M. M., Bezanilla F. Activation of squid axon K+ channels. Ionic and gating current studies. J Gen Physiol. 1985 Apr;85(4):539–554. doi: 10.1085/jgp.85.4.539. [DOI] [PMC free article] [PubMed] [Google Scholar]
  67. Yeh J. Z., Oxford G. S., Wu C. H., Narahashi T. Dynamics of aminopyridine block of potassium channels in squid axon membrane. J Gen Physiol. 1976 Nov;68(5):519–535. doi: 10.1085/jgp.68.5.519. [DOI] [PMC free article] [PubMed] [Google Scholar]
  68. Yool A. J., Schwarz T. L. Alteration of ionic selectivity of a K+ channel by mutation of the H5 region. Nature. 1991 Feb 21;349(6311):700–704. doi: 10.1038/349700a0. [DOI] [PubMed] [Google Scholar]
  69. Yue D. T., Marban E. A novel cardiac potassium channel that is active and conductive at depolarized potentials. Pflugers Arch. 1988 Dec;413(2):127–133. doi: 10.1007/BF00582522. [DOI] [PubMed] [Google Scholar]
  70. Zagotta W. N., Aldrich R. W. Voltage-dependent gating of Shaker A-type potassium channels in Drosophila muscle. J Gen Physiol. 1990 Jan;95(1):29–60. doi: 10.1085/jgp.95.1.29. [DOI] [PMC free article] [PubMed] [Google Scholar]

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