Abstract
Mutations in the Shaker (Sh) locus of Drosophila melanogaster have differing effects on action potential duration and repolarization in neurons as well as on A-type K+ channels (IA) in muscle. The molecular basis of three exemplary Sh alleles (ShKS133, ShE62 and Sh5) has been identified. They are point mutations in the Sh transcription unit expressing aberrant voltage-gated A-type K+ channels. Replicas of each mutation have been introduced by in vitro mutagenesis into Sh cDNA. The expression of in vitro transcribed mutant Sh cRNA in Xenopus laevis oocytes reproduced the specific phenotypic traits of each Sh allele. The lack of IA in ShKS133 is due to a missense mutation within a sequence motif occurring in all hitherto characterized voltage-gated K+ channel forming proteins. The reduction of IA in ShE62 is due to a mutation in an AG acceptor site. The intervening sequence between exons 19 and 20 is not spliced in ShE62 RNA. As a consequence, ShE62 flies do not contain the full complement of Sh K+ forming proteins. Finally, the Sh5 mutation leads to an altered voltage dependence of K+ channel activation and inactivation as well as to an accelerated rate of recovery from inactivation. This is due to a missense mutation altering the amino acid sequence of the proposed transmembrane segment S5 of the Sh K+ channels. Segment S5 is located adjacently to the presumed voltage sensor of voltage-gated ion channels. The results explain the altered properties of excitable cells in Sh mutants and provide a general model for the possible role of A-type K+ channels in modulating action potential profiles.
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- Abel T., Maniatis T. Gene regulation. Action of leucine zippers. Nature. 1989 Sep 7;341(6237):24–25. doi: 10.1038/341024a0. [DOI] [PubMed] [Google Scholar]
- Abrams T. W., Kandel E. R. Is contiguity detection in classical conditioning a system or a cellular property? Learning in Aplysia suggests a possible molecular site. Trends Neurosci. 1988 Apr;11(4):128–135. doi: 10.1016/0166-2236(88)90137-3. [DOI] [PubMed] [Google Scholar]
- Aebi M., Hornig H., Padgett R. A., Reiser J., Weissmann C. Sequence requirements for splicing of higher eukaryotic nuclear pre-mRNA. Cell. 1986 Nov 21;47(4):555–565. doi: 10.1016/0092-8674(86)90620-3. [DOI] [PubMed] [Google Scholar]
- Barbas J. A., Rubio N., Pedroso E., Pongs O., Ferrús A. Antibodies against Drosophila potassium channels identify membrane proteins across species. Brain Res Mol Brain Res. 1989 Mar;5(2):171–176. doi: 10.1016/0169-328x(89)90008-9. [DOI] [PubMed] [Google Scholar]
- Butler A., Wei A. G., Baker K., Salkoff L. A family of putative potassium channel genes in Drosophila. Science. 1989 Feb 17;243(4893):943–947. doi: 10.1126/science.2493160. [DOI] [PubMed] [Google Scholar]
- Crow T. Cellular and molecular analysis of associative learning and memory in Hermissenda. Trends Neurosci. 1988 Apr;11(4):136–147. doi: 10.1016/0166-2236(88)90138-5. [DOI] [PubMed] [Google Scholar]
- Ferrús A., Llamazares S., de la Pompa J. L., Tanouye M. A., Pongs O. Genetic analysis of the Shaker gene complex of Drosophila melanogaster. Genetics. 1990 Jun;125(2):383–398. doi: 10.1093/genetics/125.2.383. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frech G. C., VanDongen A. M., Schuster G., Brown A. M., Joho R. H. A novel potassium channel with delayed rectifier properties isolated from rat brain by expression cloning. Nature. 1989 Aug 24;340(6235):642–645. doi: 10.1038/340642a0. [DOI] [PubMed] [Google Scholar]
- Gisselmann G., Sewing S., Madsen B. W., Mallart A., Angaut-Petit D., Müller-Holtkamp F., Ferrus A., Pongs O. The interference of truncated with normal potassium channel subunits leads to abnormal behaviour in transgenic Drosophila melanogaster. EMBO J. 1989 Aug;8(8):2359–2364. doi: 10.1002/j.1460-2075.1989.tb08364.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Haugland F. N., Wu C. F. A voltage-clamp analysis of gene-dosage effects of the Shaker locus on larval muscle potassium currents in Drosophila. J Neurosci. 1990 Apr;10(4):1357–1371. doi: 10.1523/JNEUROSCI.10-04-01357.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Iverson L. E., Tanouye M. A., Lester H. A., Davidson N., Rudy B. A-type potassium channels expressed from Shaker locus cDNA. Proc Natl Acad Sci U S A. 1988 Aug;85(15):5723–5727. doi: 10.1073/pnas.85.15.5723. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kamb A., Iverson L. E., Tanouye M. A. Molecular characterization of Shaker, a Drosophila gene that encodes a potassium channel. Cell. 1987 Jul 31;50(3):405–413. doi: 10.1016/0092-8674(87)90494-6. [DOI] [PubMed] [Google Scholar]
- Kamb A., Tseng-Crank J., Tanouye M. A. Multiple products of the Drosophila Shaker gene may contribute to potassium channel diversity. Neuron. 1988 Jul;1(5):421–430. doi: 10.1016/0896-6273(88)90192-4. [DOI] [PubMed] [Google Scholar]
- Kramer W., Drutsa V., Jansen H. W., Kramer B., Pflugfelder M., Fritz H. J. The gapped duplex DNA approach to oligonucleotide-directed mutation construction. Nucleic Acids Res. 1984 Dec 21;12(24):9441–9456. doi: 10.1093/nar/12.24.9441. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Landschulz W. H., Johnson P. F., McKnight S. L. The leucine zipper: a hypothetical structure common to a new class of DNA binding proteins. Science. 1988 Jun 24;240(4860):1759–1764. doi: 10.1126/science.3289117. [DOI] [PubMed] [Google Scholar]
- MacKinnon R., Miller C. Mutant potassium channels with altered binding of charybdotoxin, a pore-blocking peptide inhibitor. Science. 1989 Sep 22;245(4924):1382–1385. doi: 10.1126/science.2476850. [DOI] [PubMed] [Google Scholar]
- Mount S. M. A catalogue of splice junction sequences. Nucleic Acids Res. 1982 Jan 22;10(2):459–472. doi: 10.1093/nar/10.2.459. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pongs O., Kecskemethy N., Müller R., Krah-Jentgens I., Baumann A., Kiltz H. H., Canal I., Llamazares S., Ferrus A. Shaker encodes a family of putative potassium channel proteins in the nervous system of Drosophila. EMBO J. 1988 Apr;7(4):1087–1096. doi: 10.1002/j.1460-2075.1988.tb02917.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reed R., Maniatis T. Intron sequences involved in lariat formation during pre-mRNA splicing. Cell. 1985 May;41(1):95–105. doi: 10.1016/0092-8674(85)90064-9. [DOI] [PubMed] [Google Scholar]
- Reed R. The organization of 3' splice-site sequences in mammalian introns. Genes Dev. 1989 Dec;3(12B):2113–2123. doi: 10.1101/gad.3.12b.2113. [DOI] [PubMed] [Google Scholar]
- Saiki R. K., Scharf S., Faloona F., Mullis K. B., Horn G. T., Erlich H. A., Arnheim N. Enzymatic amplification of beta-globin genomic sequences and restriction site analysis for diagnosis of sickle cell anemia. Science. 1985 Dec 20;230(4732):1350–1354. doi: 10.1126/science.2999980. [DOI] [PubMed] [Google Scholar]
- Salkoff L. Genetic and voltage-clamp analysis of a Drosophila potassium channel. Cold Spring Harb Symp Quant Biol. 1983;48(Pt 1):221–231. doi: 10.1101/sqb.1983.048.01.025. [DOI] [PubMed] [Google Scholar]
- Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [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]
- Solc C. K., Zagotta W. N., Aldrich R. W. Single-channel and genetic analyses reveal two distinct A-type potassium channels in Drosophila. Science. 1987 May 29;236(4805):1094–1098. doi: 10.1126/science.2437657. [DOI] [PubMed] [Google Scholar]
- Steller H., Pirrotta V. A transposable P vector that confers selectable G418 resistance to Drosophila larvae. EMBO J. 1985 Jan;4(1):167–171. doi: 10.1002/j.1460-2075.1985.tb02332.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stühmer W., Conti F., Suzuki H., Wang X. D., Noda M., Yahagi N., Kubo H., Numa S. Structural parts involved in activation and inactivation of the sodium channel. Nature. 1989 Jun 22;339(6226):597–603. doi: 10.1038/339597a0. [DOI] [PubMed] [Google Scholar]
- Stühmer W., Methfessel C., Sakmann B., Noda M., Numa S. Patch clamp characterization of sodium channels expressed from rat brain cDNA. Eur Biophys J. 1987;14(3):131–138. doi: 10.1007/BF00253837. [DOI] [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]
- 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]
- Tanouye M. A., Ferrus A. Action potentials in normal and Shaker mutant Drosophila. J Neurogenet. 1985 Sep;2(4):253–271. doi: 10.3109/01677068509102322. [DOI] [PubMed] [Google Scholar]
- Tanouye M. A., Ferrus A., Fujita S. C. Abnormal action potentials associated with the Shaker complex locus of Drosophila. Proc Natl Acad Sci U S A. 1981 Oct;78(10):6548–6552. doi: 10.1073/pnas.78.10.6548. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Timpe L. C., Jan L. Y. Gene dosage and complementation analysis of the Shaker locus in Drosophila. J Neurosci. 1987 May;7(5):1307–1317. doi: 10.1523/JNEUROSCI.07-05-01307.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Timpe L. C., Jan Y. N., Jan L. Y. Four cDNA clones from the Shaker locus of Drosophila induce kinetically distinct A-type potassium currents in Xenopus oocytes. Neuron. 1988 Oct;1(8):659–667. doi: 10.1016/0896-6273(88)90165-1. [DOI] [PubMed] [Google Scholar]
- Timpe L. C., Schwarz T. L., Tempel B. L., Papazian D. M., Jan Y. N., Jan L. Y. Expression of functional potassium channels from Shaker cDNA in Xenopus oocytes. Nature. 1988 Jan 14;331(6152):143–145. doi: 10.1038/331143a0. [DOI] [PubMed] [Google Scholar]
- Wu C. F., Haugland F. N. Voltage clamp analysis of membrane currents in larval muscle fibers of Drosophila: alteration of potassium currents in Shaker mutants. J Neurosci. 1985 Oct;5(10):2626–2640. doi: 10.1523/JNEUROSCI.05-10-02626.1985. [DOI] [PMC free article] [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]
- Zagotta W. N., Aldrich R. W. Alterations in activation gating of single Shaker A-type potassium channels by the Sh5 mutation. J Neurosci. 1990 Jun;10(6):1799–1810. doi: 10.1523/JNEUROSCI.10-06-01799.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]