Swiss-Prot entry
ID KAT1_ARATH STANDARD; PRT; 677 AA.
AC Q39128; Q42426;
DT 29-MAR-2004 (Rel. 43, Created)
DT 29-MAR-2004 (Rel. 43, Last sequence update)
DT 10-MAY-2005 (Rel. 47, Last annotation update)
DE Potassium channel KAT1.
GN Name=KAT1; OrderedLocusNames=At5g46240; ORFNames=MPL12.2;
OS Arabidopsis thaliana (Mouse-ear cress).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliophyta; eudicotyledons; core eudicotyledons;
OC rosids; eurosids II; Brassicales; Brassicaceae; Arabidopsis.
OX NCBI_TaxID=3702;
RN [1]
RP NUCLEOTIDE SEQUENCE.
RX MEDLINE=92237243; PubMed=1570292 [NCBI, ExPASy, EBI, Israel, Japan];
RA Anderson J.A., Huprikar S.S., Kochian L.V., Lucas W.J., Gaber R.F.;
RT "Functional expression of a probable Arabidopsis thaliana potassium
RT channel in Saccharomyces cerevisiae.";
RL Proc. Natl. Acad. Sci. U.S.A. 89:3736-3740(1992).
RN [2]
RP NUCLEOTIDE SEQUENCE, AND TISSUE SPECIFICITY.
RC STRAIN=cv. RLD;
RX MEDLINE=96030243; PubMed=7480337 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1104/pp.109.2.371;
RA Nakamura R.L., McKendree W.L. Jr., Hirsch R.E., Sedbrook J.C.,
RA Gaber R.F., Sussman M.R.;
RT "Expression of an Arabidopsis potassium channel gene in guard cells.";
RL Plant Physiol. 109:371-374(1995).
RN [3]
RP NUCLEOTIDE SEQUENCE.
RC STRAIN=cv. Landsberg erecta;
RX MEDLINE=96394359; PubMed=8798465 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1074/jbc.271.37.22863;
RA Gaymard F., Cerrutti M., Horeau C., Lemaillet G., Urbach S.,
RA Ravallec M., Devauchelle G., Sentenac H., Thibaud J.-B.;
RT "The baculovirus/insect cell system as an alternative to Xenopus
RT oocytes. First characterization of the AKT1 K+ channel from
RT Arabidopsis thaliana.";
RL J. Biol. Chem. 271:22863-22870(1996).
RN [4]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=cv. Columbia;
RX MEDLINE=98344145; PubMed=9679202 [NCBI, ExPASy, EBI, Israel, Japan];
RA Kaneko T., Kotani H., Nakamura Y., Sato S., Asamizu E., Miyajima N.,
RA Tabata S.;
RT "Structural analysis of Arabidopsis thaliana chromosome 5. V. Sequence
RT features of the regions of 1,381,565 bp covered by twenty one
RT physically assigned P1 and TAC clones.";
RL DNA Res. 5:131-145(1998).
RN [5]
RP FUNCTION.
RX MEDLINE=97119799; PubMed=8966547 [NCBI, ExPASy, EBI, Israel, Japan];
RA Schachtman D.P., Schroeder J.I., Lucas W.J., Anderson J.A.,
RA Gaber R.F.;
RT "Expression of an inward-rectifying potassium channel by the
RT Arabidopsis KAT1 cDNA.";
RL Science 258:1654-1658(1992).
RN [6]
RP PORE SELECTIVITY, AND MUTAGENESIS OF THR-256.
RX PubMed=7592636 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1074/jbc.270.41.24276;
RA Uozumi N., Gassmann W., Cao Y., Schroeder J.I.;
RT "Identification of strong modifications in cation selectivity in an
RT Arabidopsis inward rectifying potassium channel by mutant selection in
RT yeast.";
RL J. Biol. Chem. 270:24276-24281(1995).
RN [7]
RP PORE SELECTIVITY, AND MUTAGENESIS OF LEU-251; THR-256; THR-259;
RP THR-260 AND 259-THR-THR-260.
RX PubMed=8755614 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1073/pnas.93.15.8123;
RA Becker D., Dreyer I., Hoth S., Reid J.D., Busch H., Lehnen M.,
RA Palme K., Hedrich R.;
RT "Changes in voltage activation, Cs+ sensitivity, and ion permeability
RT in H5 mutants of the plant K+ channel KAT1.";
RL Proc. Natl. Acad. Sci. U.S.A. 93:8123-8128(1996).
RN [8]
RP PORE SELECTIVITY, AND MUTAGENESIS OF TYR-263 AND GLY-264.
RX PubMed=8995396 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1074/jbc.272.25.15834;
RA Nakamura R.L., Anderson J.A., Gaber R.F.;
RT "Determination of key structural requirements of a K+ channel pore.";
RL J. Biol. Chem. 272:1011-1018(1997).
RN [9]
RP PORE SELECTIVITY, AND MUTAGENESIS OF HIS-267 AND GLU-269.
RX PubMed=9368418 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1105/tpc.9.10.1843;
RA Ichida A.M., Pei Z.-M., Baizabal-Aguirre V.M., Turner K.J.,
RA Schroeder J.I.;
RT "Expression of a Cs(+)-resistant guard cell K+ channel confers Cs(+)-
RT resistant, light-induced stomatal opening in transgenic Arabidopsis.";
RL Plant Cell 9:1843-1857(1997).
RN [10]
RP PORE SELECTIVITY, AND MUTAGENESIS OF THR-256 AND HIS-267.
RX PubMed=9688573 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1016/S0014-5793(98)00694-2;
RA Dreyer I., Becker D., Bregante M., Gambale F., Lehnen M., Palme K.,
RA Hedrich R.;
RT "Single mutations strongly alter the K(+)-selective pore of the K(in)
RT channel KAT1.";
RL FEBS Lett. 430:370-376(1998).
RN [11]
RP VOLTAGE-DEPENDENT GATING, AND MUTAGENESIS OF ARG-176.
RX MEDLINE=98297672; PubMed=9635749 [NCBI, ExPASy, EBI, Israel, Japan];
RA Marten I., Hoshi T.;
RT "The N-terminus of the K channel KAT1 controls its voltage-dependent
RT gating by altering the membrane electric field.";
RL Biophys. J. 74:2953-2962(1998).
RN [12]
RP VOLTAGE-DEPENDENT GATING, AND MUTAGENESIS OF ARG-176 AND ARG-177.
RX MEDLINE=99054767; PubMed=9834140 [NCBI, ExPASy, EBI, Israel, Japan];
RA Zei P.C., Aldrich R.W.;
RT "Voltage-dependent gating of single wild-type and S4 mutant KAT1
RT inward rectifier potassium channels.";
RL J. Gen. Physiol. 112:679-713(1998).
RN [13]
RP INTERACTION WITH AKT2, AND MUTAGENESIS OF THR-256 AND GLY-262.
RX MEDLINE=99115721; PubMed=9916143 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1007/s002329900476;
RA Baizabal-Aguirre V.M., Clemens S., Uozumi N., Schroeder J.I.;
RT "Suppression of inward-rectifying K+ channels KAT1 and AKT2 by
RT dominant negative point mutations in the KAT1 alpha-subunit.";
RL J. Membr. Biol. 167:119-125(1999).
RN [14]
RP PROTON SENSITIVITY, AND MUTAGENESIS OF ASP-265.
RX PubMed=10206968 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1074/jbc.274.17.11599;
RA Hoth S., Hedrich R.;
RT "Distinct molecular bases for pH sensitivity of the guard cell K+
RT channels KST1 and KAT1.";
RL J. Biol. Chem. 274:11599-11603(1999).
RN [15]
RP INTERACTION WITH KAT2.
RX MEDLINE=21264790; PubMed=11042178 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1074/jbc.M007303200;
RA Pilot G., Lacombe B., Gaymard F., Cherel I., Boucherez J.,
RA Thibaud J.-B., Sentenac H.;
RT "Guard cell inward K+ channel activity in Arabidopsis involves
RT expression of the twin channel subunits KAT1 and KAT2.";
RL J. Biol. Chem. 276:3215-3221(2001).
RN [16]
RP GENE FAMILY, AND NOMENCLATURE.
RX MEDLINE=21392307; PubMed=11500563 [NCBI, ExPASy, EBI, Israel, Japan]; DOI=10.1104/pp.126.4.1646;
RA Maeser P., Thomine S., Schroeder J.I., Ward J.M., Hirschi K., Sze H.,
RA Talke I.N., Amtmann A., Maathuis F.J.M., Sanders D., Harper J.F.,
RA Tchieu J., Gribskov M., Persans M.W., Salt D.E., Kim S.A.,
RA Guerinot M.L.;
RT "Phylogenetic relationships within cation transporter families of
RT Arabidopsis.";
RL Plant Physiol. 126:1646-1667(2001).
CC -!- FUNCTION: Highly selective inward-rectifying potassium channel.
CC This voltage-gated channel could mediate long-term potassium
CC influx into guard cells leading to stomatal opening. Assuming
CC opened or closed conformations in response to the voltage
CC difference across the membrane, the channel is activated by
CC hyperpolarization. The channel activity is enhanced upon external
CC acidification. Also permeable to ammonium ions. Blocked by
CC tetraethylammonium and barium ions.
CC -!- SUBUNIT: The potassium channel is probably composed of a homo- or
CC heterotetrameric complex of pore-forming subunits. May interact
CC with AKT2 and KAT2.
CC -!- SUBCELLULAR LOCATION: Integral membrane protein.
CC -!- TISSUE SPECIFICITY: Expressed in guard cells, and in roots.
CC -!- DOMAIN: The segment S4 is probably the voltage-sensor and is
CC characterized by a series of positively charged amino acids. The
CC pore-forming region H5 is enclosed by the transmembrane segments
CC S5 and S6 in the Shaker-type (1P/6TM) and contains the GYGD
CC signature motif which seems to be involved in potassium
CC selectivity.
CC -!- DOMAIN: The KHA domain (rich in hydrophobic and acidic residues)
CC present in the C-terminal part is likely to be important for
CC tetramerization.
CC -!- SIMILARITY: Belongs to the potassium channel (TC 1.A.1.4) family.
CC -!- SIMILARITY: Contains 1 cyclic nucleotide-binding domain.
CC -!- SIMILARITY: Contains 1 KHA domain.
CC --------------------------------------------------------------------------
CC This Swiss-Prot entry is copyright. It is produced through a collaboration
CC between the Swiss Institute of Bioinformatics and the EMBL outstation -
CC the European Bioinformatics Institute. There are no restrictions on its
CC use as long as its content is in no way modified and this statement is not
CC removed.
CC --------------------------------------------------------------------------
DR EMBL; M86990; AAA32824.1; -; mRNA. [EMBL / GenBank / DDBJ] [CoDingSequence]
DR EMBL; U25088; AAC49113.1; -; Genomic_DNA. [EMBL / GenBank / DDBJ] [CoDingSequence]
DR EMBL; X93022; CAA63601.1; -; mRNA. [EMBL / GenBank / DDBJ] [CoDingSequence]
DR EMBL; AB010698; BAB11079.1; -; Genomic_DNA. [EMBL / GenBank / DDBJ] [CoDingSequence]
DR PIR; S32816; S32816.
DR GeneFarm; 2592; 266.
DR InterPro; IPR000595; cNMP_binding.
DR InterPro; IPR003938; EAG_ELK_ERG.
DR InterPro; IPR005821; Ion_trans.
DR InterPro; IPR001622; K+channel_pore.
DR InterPro; IPR005820; M+channel_nlg.
DR InterPro; Graphical view of domain structure.
DR Pfam; PF00027; cNMP_binding; 1.
DR Pfam; PF00520; Ion_trans; 1.
DR Pfam; Graphical view of domain structure.
DR PRINTS; PR01463; EAGCHANLFMLY.
DR SMART; SM00100; cNMP; 1.
DR PROSITE; PS00888; CNMP_BINDING_1; FALSE_NEG.
DR PROSITE; PS00889; CNMP_BINDING_2; FALSE_NEG.
DR PROSITE; PS50042; CNMP_BINDING_3; 1.
DR CMR; Q39128.
DR ProDom [Domain structure / List of seq. sharing at least 1 domain]
DR BLOCKS; Q39128.
DR ProtoNet; Q39128.
DR ProtoMap; Q39128.
DR PRESAGE; Q39128.
DR DIP; Q39128.
DR ModBase; Q39128.
DR TAIR; At5g46240.
DR SWISS-2DPAGE; GET REGION ON 2D PAGE.
KW Ion transport; Ionic channel; Potassium; Potassium channel;
KW Potassium transport; Transmembrane; Transport; Voltage-gated channel.
FT TOPO_DOM 1 63 Cytoplasmic (Potential).
FT TRANSMEM 64 84 Segment S1 (Potential).
FT TRANSMEM 91 111 Segment S2 (Potential).
FT TOPO_DOM 112 134 Cytoplasmic (Potential).
FT TRANSMEM 135 155 Segment S3 (Potential).
FT TRANSMEM 166 186 Segment S4 (Potential).
FT TOPO_DOM 187 200 Cytoplasmic (Potential).
FT TRANSMEM 201 221 Segment S5 (Potential).
FT TRANSMEM 273 293 Segment S6 (Potential).
FT TOPO_DOM 294 677 Cytoplasmic (Potential).
FT DOMAIN 623 677 KHA.
FT NP_BIND 377 496 cNMP.
FT REGION 249 268 Segment H5 (pore-forming, in membrane)
FT (Potential).
FT MUTAGEN 176 176 R->S,L: Affects the voltage-dependent
FT gating.
FT MUTAGEN 177 177 R->Q: Affects the voltage-dependent
FT gating.
FT MUTAGEN 251 251 L->I,F: Enhances cesium sensitivity.
FT MUTAGEN 256 256 T->D,G,Q,E: Increases sensitivity to
FT ammonium and sodium.
FT MUTAGEN 256 256 T->E: Increases rubidium uptake and both
FT cesium and calcium sensitivity;
FT facilitated entry of calcium ions; when
FT associated with A-267.
FT MUTAGEN 256 256 T->F,L,P,R,W: Abolishes channel activity.
FT MUTAGEN 256 256 T->S: Increases calcium sensitivity;
FT facilitated entry of calcium ions; when
FT associated with A-267.
FT MUTAGEN 259 259 T->S: Increases rubidium uptake and
FT cesium sensitivity; additional increase
FT of rubidium uptake; when associated with
FT S-260.
FT MUTAGEN 260 260 T->S: Increases rubidium uptake;
FT additional increase of rubidium uptake;
FT when associated with S-259.
FT MUTAGEN 262 262 G->K: Abolishes channel activity.
FT MUTAGEN 263 263 Y->F: The only mutation at this site that
FT do not perturb the channel activity.
FT MUTAGEN 264 264 G->C,F,K,L,P,S,T: Abolishes channel
FT activity.
FT MUTAGEN 265 265 D->N: Affects the pH-dependence.
FT MUTAGEN 267 267 H->A: Increases calcium sensitivity;
FT facilitated entry of calcium ions; when
FT associated with S-256.
FT MUTAGEN 267 267 H->T: Resistance to the cesium inhibition
FT of stomatal opening; when associated with
FT V-269.
FT MUTAGEN 269 269 E->V: Resistance to the cesium inhibition
FT of stomatal opening; when associated with
FT T-267.
FT CONFLICT 5 5 W -> C (in Ref. 3).
FT CONFLICT 330 330 Q -> E (in Ref. 3).
FT CONFLICT 573 573 V -> E (in Ref. 3).
FT CONFLICT 580 580 T -> S (in Ref. 3).
FT CONFLICT 629 629 L -> V (in Ref. 3).
FT CONFLICT 664 664 D -> N (in Ref. 3).
SQ SEQUENCE 677 AA; 78271 MW; 7F9C8285ED702338 CRC64;
MSISWTRNFF ERFCVEEYNI DTIKQSSFLS ADLLPSLGAR INQSTKLRKH IISPFNPRYR
AWEMWLVLLV IYSAWICPFQ FAFITYKKDA IFIIDNIVNG FFAIDIILTF FVAYLDSHSY
LLVDSPKKIA IRYLSTWFAF DVCSTAPFQP LSLLFNYNGS ELGFRILSML RLWRLRRVSS
LFARLEKDIR FNYFWIRCTK LISVTLFAIH CAGCFNYLIA DRYPNPRKTW IGAVYPNFKE
ASLWNRYVTA LYWSITTLTT TGYGDFHAEN PREMLFDIFF MMFNLGLTAY LIGNMTNLVV
HWTSRTRTFR DSVRAASEFA SRNQLPHDIQ DQMLSHICLK FKTEGLKQQE TLNNLPKAIR
SSIANYLFFP IVHNIYLFQG VSRNFLFQLV SDIDAEYFPP KEDIILQNEA PTDLYILVSG
AVDFTVYVDG HDQFQGKAVI GETFGEVGVL YYRPQPFTVR TTELSQILRI SRTSLMSAMH
AHADDGRVIM NNLFMKLRGQ QSIAIDDSNT SGHENRDFKS MGWEEWRDSR KDGYGLDVTN
PTSDTALMDA IHKEDTEMVK KILKEQKIER AKVERSSSET AGRSYANDSS KKDPYCSSSN
QIIKPCKREE KRVTIHMMSE SKNGKLILLP SSIEELLRLA SEKFGGCNFT KITNADNAEI
DDLDVIWDGD HLYFSSN
//