HKT21_ORYSJ
ID HKT21_ORYSJ Reviewed; 530 AA.
AC Q0D9S3; A0A0P0X0T3; Q6TPH3; Q7GC01; Q8L6H6; Q8W1B8; Q9FPN6;
DT 11-SEP-2007, integrated into UniProtKB/Swiss-Prot.
DT 17-OCT-2006, sequence version 1.
DT 03-AUG-2022, entry version 84.
DE RecName: Full=Cation transporter HKT2;1 {ECO:0000303|PubMed:16809061};
DE Short=OsHKT2;1 {ECO:0000303|PubMed:16809061};
DE AltName: Full=Cation transporter HKT1 {ECO:0000303|PubMed:12795699};
DE Short=OsHKT1 {ECO:0000303|PubMed:12795699};
DE AltName: Full=Ni-OsHKT1 {ECO:0000303|PubMed:11489190};
GN Name=HKT2;1 {ECO:0000303|PubMed:16809061};
GN Synonyms=HKT1 {ECO:0000303|PubMed:12795699};
GN OrderedLocusNames=Os06g0701700 {ECO:0000312|EMBL:BAS99352.1},
GN LOC_Os06g48810 {ECO:0000305};
GN ORFNames=P0596H10.9 {ECO:0000312|EMBL:BAD53775.1};
OS Oryza sativa subsp. japonica (Rice).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; Liliopsida; Poales; Poaceae; BOP clade;
OC Oryzoideae; Oryzeae; Oryzinae; Oryza; Oryza sativa.
OX NCBI_TaxID=39947;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, AND INDUCTION.
RC STRAIN=cv. Nipponbare; TISSUE=Seedling root;
RX PubMed=11489190; DOI=10.1046/j.1365-313x.2001.01077.x;
RA Horie T., Yoshida K., Nakayama H., Yamada K., Oiki S., Shinmyo A.;
RT "Two types of HKT transporters with different properties of Na+ and K+
RT transport in Oryza sativa.";
RL Plant J. 27:129-138(2001).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES,
RP INDUCTION, AND NOMENCLATURE.
RC STRAIN=cv. Nipponbare;
RX PubMed=12795699; DOI=10.1046/j.1365-313x.2003.01764.x;
RA Garciadeblas B., Senn M.E., Banuelos M.A., Rodriguez-Navarro A.;
RT "Sodium transport and HKT transporters: the rice model.";
RL Plant J. 34:788-801(2003).
RN [3]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=cv. Nipponbare;
RX PubMed=16100779; DOI=10.1038/nature03895;
RG International rice genome sequencing project (IRGSP);
RT "The map-based sequence of the rice genome.";
RL Nature 436:793-800(2005).
RN [4]
RP GENOME REANNOTATION.
RC STRAIN=cv. Nipponbare;
RX PubMed=18089549; DOI=10.1093/nar/gkm978;
RG The rice annotation project (RAP);
RT "The rice annotation project database (RAP-DB): 2008 update.";
RL Nucleic Acids Res. 36:D1028-D1033(2008).
RN [5]
RP GENOME REANNOTATION.
RC STRAIN=cv. Nipponbare;
RX PubMed=24280374; DOI=10.1186/1939-8433-6-4;
RA Kawahara Y., de la Bastide M., Hamilton J.P., Kanamori H., McCombie W.R.,
RA Ouyang S., Schwartz D.C., Tanaka T., Wu J., Zhou S., Childs K.L.,
RA Davidson R.M., Lin H., Quesada-Ocampo L., Vaillancourt B., Sakai H.,
RA Lee S.S., Kim J., Numa H., Itoh T., Buell C.R., Matsumoto T.;
RT "Improvement of the Oryza sativa Nipponbare reference genome using next
RT generation sequence and optical map data.";
RL Rice 6:4-4(2013).
RN [6]
RP FUNCTION, DOMAIN, AND MUTAGENESIS OF SER-88.
RX PubMed=11959905; DOI=10.1073/pnas.082123799;
RA Maeser P., Hosoo Y., Goshima S., Horie T., Eckelman B., Yamada K.,
RA Yoshida K., Bakker E.P., Shinmyo A., Oiki S., Schroeder J.I., Uozumi N.;
RT "Glycine residues in potassium channel-like selectivity filters determine
RT potassium selectivity in four-loop-per-subunit HKT transporters from
RT plants.";
RL Proc. Natl. Acad. Sci. U.S.A. 99:6428-6433(2002).
RN [7]
RP GENE FAMILY, AND NOMENCLATURE.
RX PubMed=16809061; DOI=10.1016/j.tplants.2006.06.001;
RA Platten J.D., Cotsaftis O., Berthomieu P., Bohnert H., Davenport R.J.,
RA Fairbairn D.J., Horie T., Leigh R.A., Lin H.X., Luan S., Maeser P.,
RA Pantoja O., Rodriguez-Navarro A., Schachtman D.P., Schroeder J.I.,
RA Sentenac H., Uozumi N., Very A.A., Zhu J.K., Dennis E.S., Tester M.;
RT "Nomenclature for HKT transporters, key determinants of plant salinity
RT tolerance.";
RL Trends Plant Sci. 11:372-374(2006).
RN [8]
RP FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY, INDUCTION, AND
RP DISRUPTION PHENOTYPE.
RX PubMed=17541409; DOI=10.1038/sj.emboj.7601732;
RA Horie T., Costa A., Kim T.H., Han M.J., Horie R., Leung H.Y., Miyao A.,
RA Hirochika H., An G., Schroeder J.I.;
RT "Rice OsHKT2;1 transporter mediates large Na+ influx component into K+-
RT starved roots for growth.";
RL EMBO J. 26:3003-3014(2007).
RN [9]
RP FUNCTION, AND TISSUE SPECIFICITY.
RX PubMed=19482918; DOI=10.1104/pp.109.138008;
RA Jabnoune M., Espeout S., Mieulet D., Fizames C., Verdeil J.L., Conejero G.,
RA Rodriguez-Navarro A., Sentenac H., Guiderdoni E., Abdelly C., Very A.A.;
RT "Diversity in expression patterns and functional properties in the rice HKT
RT transporter family.";
RL Plant Physiol. 150:1955-1971(2009).
RN [10]
RP FUNCTION.
RX PubMed=30854552; DOI=10.1093/jxb/erz113;
RA Hartley T.N., Thomas A.S., Maathuis F.J.M.;
RT "A role for the OsHKT 2;1 sodium transporter in potassium use efficiency in
RT rice.";
RL J. Exp. Bot. 71:699-706(2020).
CC -!- FUNCTION: Seems to be involved in regulation of potassium-sodium
CC homeostasis (PubMed:11489190, PubMed:12795699, PubMed:11959905).
CC Functions as a high-affinity sodium transporter, which mediates
CC increased sodium uptake in roots under potassium deficiency and
CC contributes to sodium accumulation and salt toxicity (PubMed:11489190,
CC PubMed:12795699, PubMed:11959905). Involved in nutritional sodium
CC uptake and distribution in potassium-starved roots to allow plant
CC growth (PubMed:17541409, PubMed:30854552). Functions as sodium-
CC potassium cotransporter (PubMed:19482918).
CC {ECO:0000269|PubMed:11489190, ECO:0000269|PubMed:11959905,
CC ECO:0000269|PubMed:12795699, ECO:0000269|PubMed:17541409,
CC ECO:0000269|PubMed:19482918, ECO:0000269|PubMed:30854552}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=Na(+)(in) = Na(+)(out); Xref=Rhea:RHEA:34963,
CC ChEBI:CHEBI:29101; Evidence={ECO:0000269|PubMed:11489190,
CC ECO:0000269|PubMed:11959905, ECO:0000269|PubMed:12795699};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=K(+)(in) + Na(+)(in) = K(+)(out) + Na(+)(out);
CC Xref=Rhea:RHEA:71639, ChEBI:CHEBI:29101, ChEBI:CHEBI:29103;
CC Evidence={ECO:0000269|PubMed:19482918};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=20 uM for Na(+) {ECO:0000269|PubMed:12795699};
CC Vmax=15 nmol/min/mg enzyme with sodium as ion
CC {ECO:0000269|PubMed:12795699};
CC Note=Measured in yeast strain disrupted for potassium transporters
CC TRK1 and TRK2.;
CC -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000269|PubMed:17541409};
CC Multi-pass membrane protein {ECO:0000255}. Note=Localizes to the plasma
CC membrane. {ECO:0000269|PubMed:17541409}.
CC -!- TISSUE SPECIFICITY: Expressed in cortical and endodermal cells in roots
CC and in vascular bundle regions in leaves (PubMed:17541409). In roots,
CC expressed in epidermis, exodermis, cortex, and sieve elements and
CC companion cells of phloem (PubMed:19482918). In mature leaves,
CC expressed in large highly vacuolated cells of the adaxial epidermis,
CC phloem and xylem (PubMed:19482918). {ECO:0000269|PubMed:17541409,
CC ECO:0000269|PubMed:19482918}.
CC -!- INDUCTION: Induced by potassium starvation in roots (PubMed:11489190,
CC PubMed:12795699, PubMed:17541409). Down-regulated by sodium, potassium,
CC rubidium, lithium and cesium (PubMed:11489190, PubMed:12795699).
CC {ECO:0000269|PubMed:11489190, ECO:0000269|PubMed:12795699,
CC ECO:0000269|PubMed:17541409}.
CC -!- DOMAIN: HKT transporters are proposed to contain 4 pore-forming regions
CC enclosed by transmembrane segments with each containing a potassium
CC channel-like selectivity filter motif. {ECO:0000269|PubMed:11959905}.
CC -!- DISRUPTION PHENOTYPE: Reduced accumulation of sodium in roots and
CC shoots (PubMed:17541409). Reduced growth under low sodium and potassium
CC starvation conditions (PubMed:17541409). {ECO:0000269|PubMed:17541409}.
CC -!- SIMILARITY: Belongs to the TrkH potassium transport family. HKT (TC
CC 2.A.38.3) subfamily. {ECO:0000305}.
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DR EMBL; AB061311; BAB61789.1; -; mRNA.
DR EMBL; AJ491852; CAD37196.1; -; Genomic_DNA.
DR EMBL; AP003726; BAD53775.1; -; Genomic_DNA.
DR EMBL; AP008212; BAF20400.1; -; Genomic_DNA.
DR EMBL; AP014962; BAS99352.1; -; Genomic_DNA.
DR RefSeq; XP_015641242.1; XM_015785756.1.
DR AlphaFoldDB; Q0D9S3; -.
DR SMR; Q0D9S3; -.
DR BioGRID; 811008; 1.
DR STRING; 4530.OS06T0701700-01; -.
DR TCDB; 2.A.38.3.3; the k(+) transporter (trk) family.
DR PaxDb; Q0D9S3; -.
DR PRIDE; Q0D9S3; -.
DR EnsemblPlants; Os06t0701700-01; Os06t0701700-01; Os06g0701700.
DR GeneID; 4341971; -.
DR Gramene; Os06t0701700-01; Os06t0701700-01; Os06g0701700.
DR KEGG; osa:4341971; -.
DR eggNOG; KOG1341; Eukaryota.
DR HOGENOM; CLU_008384_2_0_1; -.
DR InParanoid; Q0D9S3; -.
DR OMA; IIMMYLP; -.
DR OrthoDB; 385384at2759; -.
DR SABIO-RK; Q0D9S3; -.
DR Proteomes; UP000000763; Chromosome 6.
DR Proteomes; UP000059680; Chromosome 6.
DR ExpressionAtlas; Q0D9S3; baseline and differential.
DR Genevisible; Q0D9S3; OS.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0005886; C:plasma membrane; IBA:GO_Central.
DR GO; GO:0008324; F:cation transmembrane transporter activity; IBA:GO_Central.
DR GO; GO:0006813; P:potassium ion transport; IEA:UniProtKB-KW.
DR GO; GO:0006814; P:sodium ion transport; IEA:UniProtKB-KW.
DR InterPro; IPR003445; Cat_transpt.
DR Pfam; PF02386; TrkH; 1.
PE 1: Evidence at protein level;
KW Cell membrane; Ion transport; Membrane; Potassium; Potassium transport;
KW Reference proteome; Sodium; Sodium transport; Transmembrane;
KW Transmembrane helix; Transport.
FT CHAIN 1..530
FT /note="Cation transporter HKT2;1"
FT /id="PRO_0000070466"
FT TOPO_DOM 1..40
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT TRANSMEM 41..61
FT /note="Helical; Name=1"
FT /evidence="ECO:0000255"
FT TRANSMEM 102..122
FT /note="Helical; Name=2"
FT /evidence="ECO:0000255"
FT TOPO_DOM 123..186
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT TRANSMEM 187..207
FT /note="Helical; Name=3"
FT /evidence="ECO:0000255"
FT TRANSMEM 260..280
FT /note="Helical; Name=4"
FT /evidence="ECO:0000255"
FT TOPO_DOM 281..317
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT TRANSMEM 318..338
FT /note="Helical; Name=5"
FT /evidence="ECO:0000255"
FT TRANSMEM 372..392
FT /note="Helical; Name=6"
FT /evidence="ECO:0000255"
FT TOPO_DOM 393..418
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT TRANSMEM 419..439
FT /note="Helical; Name=7"
FT /evidence="ECO:0000255"
FT TRANSMEM 494..514
FT /note="Helical; Name=8"
FT /evidence="ECO:0000255"
FT TOPO_DOM 515..530
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT MUTAGEN 88
FT /note="S->G: Conveys selectivity for potassium uptake."
FT /evidence="ECO:0000269|PubMed:11959905"
FT CONFLICT 65
FT /note="S -> T (in Ref. 3; CAD37196)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 530 AA; 59295 MW; F98F41277E3881CF CRC64;
MTSIYHDFIH NKLQSFGRIG RYFVNFVVLA HRFIALHIHP FWIQLSYFLL ISILGSVLLM
FLKPSNPEFR PGYIDMLFLS TSALTLSSLI TIEMEVLSSS QIVVITLLML LGGEVFVSFL
GLMLRLNHKH NPEFSGDKVS SVPIELDTIN SASTVISCEE LQLEAAIPEV PSSTIKDLKR
SKRLRWFLGF VVFSYFVVIH VAGFLLVLWY ISRVSSAKAP LKKKGINIAL FSFSVTVSSF
ANVGLVPTNE NMAIFSKNPG LLLLFIGQIL AGNTLYPLFL RLLIWFLGKV TKLRELKLMI
KNPEELQYDY LLPKLPTAFL ASTVIGLMAS LVTLFGAVDW NSSVFDGLSS YQKIINALFM
AVNARHSGEN SIDCSLIAPA VLVLFIILMY LPPSTTFALS NGDEKTANKK AKRKLGLVVQ
NLAFSQLACI SVFVIVAFIT ERSRLRNDPL NFSALNMIFE IISAYGNVGL STGYSCSRLQ
KLHPGSICQD KPYSLSGWWS DEGKLLLVFV MLYGRLKAFT KGTGEYWRLW
