Abstract
We have cloned a cDNA (designated RAK) coding for a delayed-rectifier K current (IRAK) from adult rat heart atrium and expressed it in Xenopus oocytes. RAK differs from the cloned rat brain K current, BK2 [McKinnon, D. (1989) J. Biol. Chem. 264, 8230-8236], by one amino acid at residue 411. RAK expressed in oocytes compares closely to the intrinsic adult rat atrial delayed-rectifier current measured by using whole-cell recording of single isolated cells. Northern blot analysis confirmed the presence of the channel in adult rat atrium, and to a lesser extent, in rat ventricle. IRAK activates with time constants ranging from 58 ms at -20 mV to 6 ms at +60 mV and does not show significant inactivation over 800 ms. It is blocked by 4-aminopyridine greater than barium much greater than tetraethylammonium chloride, which is similar to the relative potencies of these blockers on the native delayed rectifier current. We conclude that the main delayed rectifier K current in adult rat atria is virtually identical to a neuronal delayed rectifier, BK2.
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- Apkon M., Nerbonne J. M. Alpha 1-adrenergic agonists selectively suppress voltage-dependent K+ current in rat ventricular myocytes. Proc Natl Acad Sci U S A. 1988 Nov;85(22):8756–8760. doi: 10.1073/pnas.85.22.8756. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Baumann A., Grupe A., Ackermann A., Pongs O. Structure of the voltage-dependent potassium channel is highly conserved from Drosophila to vertebrate central nervous systems. EMBO J. 1988 Aug;7(8):2457–2463. doi: 10.1002/j.1460-2075.1988.tb03092.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennett P. B., McKinney L. C., Kass R. S., Begenisich T. Delayed rectification in the calf cardiac Purkinje fiber. Evidence for multiple state kinetics. Biophys J. 1985 Oct;48(4):553–567. doi: 10.1016/S0006-3495(85)83813-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Catterall W. A. Structure and function of voltage-sensitive ion channels. Science. 1988 Oct 7;242(4875):50–61. doi: 10.1126/science.2459775. [DOI] [PubMed] [Google Scholar]
- Chomczynski P., Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987 Apr;162(1):156–159. doi: 10.1006/abio.1987.9999. [DOI] [PubMed] [Google Scholar]
- Clapham D. E., Logothetis D. E. Delayed rectifier K+ current in embryonic chick heart ventricle. Am J Physiol. 1988 Jan;254(1 Pt 2):H192–H197. doi: 10.1152/ajpheart.1988.254.1.H192. [DOI] [PubMed] [Google Scholar]
- 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]
- Gubler U., Hoffman B. J. A simple and very efficient method for generating cDNA libraries. Gene. 1983 Nov;25(2-3):263–269. doi: 10.1016/0378-1119(83)90230-5. [DOI] [PubMed] [Google Scholar]
- 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]
- Hartzell H. C. Regulation of cardiac ion channels by catecholamines, acetylcholine and second messenger systems. Prog Biophys Mol Biol. 1988;52(3):165–247. doi: 10.1016/0079-6107(88)90014-4. [DOI] [PubMed] [Google Scholar]
- Kozak M. Point mutations define a sequence flanking the AUG initiator codon that modulates translation by eukaryotic ribosomes. Cell. 1986 Jan 31;44(2):283–292. doi: 10.1016/0092-8674(86)90762-2. [DOI] [PubMed] [Google Scholar]
- Krebs E. G., Beavo J. A. Phosphorylation-dephosphorylation of enzymes. Annu Rev Biochem. 1979;48:923–959. doi: 10.1146/annurev.bi.48.070179.004423. [DOI] [PubMed] [Google Scholar]
- Krieg P. A., Melton D. A. Functional messenger RNAs are produced by SP6 in vitro transcription of cloned cDNAs. Nucleic Acids Res. 1984 Sep 25;12(18):7057–7070. doi: 10.1093/nar/12.18.7057. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McKinnon D. Isolation of a cDNA clone coding for a putative second potassium channel indicates the existence of a gene family. J Biol Chem. 1989 May 15;264(14):8230–8236. [PubMed] [Google Scholar]
- Peralta E. G., Winslow J. W., Peterson G. L., Smith D. H., Ashkenazi A., Ramachandran J., Schimerlik M. I., Capon D. J. Primary structure and biochemical properties of an M2 muscarinic receptor. Science. 1987 May 1;236(4801):600–605. doi: 10.1126/science.3107123. [DOI] [PubMed] [Google Scholar]
- 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]
- Schwarz T. L., Tempel B. L., Papazian D. M., Jan Y. N., Jan L. Y. Multiple potassium-channel components are produced by alternative splicing at the Shaker locus in Drosophila. Nature. 1988 Jan 14;331(6152):137–142. doi: 10.1038/331137a0. [DOI] [PubMed] [Google Scholar]
- Simmons M. A., Creazzo T., Hartzell H. C. A time-dependent and voltage-sensitive K+ current in single cells from frog atrium. J Gen Physiol. 1986 Dec;88(6):739–755. doi: 10.1085/jgp.88.6.739. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stühmer W., Ruppersberg J. P., Schröter K. H., Sakmann B., Stocker M., Giese K. P., Perschke A., Baumann A., Pongs O. Molecular basis of functional diversity of voltage-gated potassium channels in mammalian brain. EMBO J. 1989 Nov;8(11):3235–3244. doi: 10.1002/j.1460-2075.1989.tb08483.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tabor S., Richardson C. C. DNA sequence analysis with a modified bacteriophage T7 DNA polymerase. Proc Natl Acad Sci U S A. 1987 Jul;84(14):4767–4771. doi: 10.1073/pnas.84.14.4767. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Tempel B. L., Jan Y. N., Jan L. Y. Cloning of a probable potassium channel gene from mouse brain. Nature. 1988 Apr 28;332(6167):837–839. doi: 10.1038/332837a0. [DOI] [PubMed] [Google Scholar]
- Tempel B. L., Papazian D. M., Schwarz T. L., Jan Y. N., Jan L. Y. Sequence of a probable potassium channel component encoded at Shaker locus of Drosophila. Science. 1987 Aug 14;237(4816):770–775. doi: 10.1126/science.2441471. [DOI] [PubMed] [Google Scholar]
- Tohse N., Kameyama M., Irisawa H. Intracellular Ca2+ and protein kinase C modulate K+ current in guinea pig heart cells. Am J Physiol. 1987 Nov;253(5 Pt 2):H1321–H1324. doi: 10.1152/ajpheart.1987.253.5.H1321. [DOI] [PubMed] [Google Scholar]
- 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]
- Walsh K. B., Kass R. S. Regulation of a heart potassium channel by protein kinase A and C. Science. 1988 Oct 7;242(4875):67–69. doi: 10.1126/science.2845575. [DOI] [PubMed] [Google Scholar]
- Woodgett J. R., Gould K. L., Hunter T. Substrate specificity of protein kinase C. Use of synthetic peptides corresponding to physiological sites as probes for substrate recognition requirements. Eur J Biochem. 1986 Nov 17;161(1):177–184. doi: 10.1111/j.1432-1033.1986.tb10139.x. [DOI] [PubMed] [Google Scholar]
- Yokoyama S., Imoto K., Kawamura T., Higashida H., Iwabe N., Miyata T., Numa S. Potassium channels from NG108-15 neuroblastoma-glioma hybrid cells. Primary structure and functional expression from cDNAs. FEBS Lett. 1989 Dec 18;259(1):37–42. doi: 10.1016/0014-5793(89)81488-7. [DOI] [PubMed] [Google Scholar]