HKT21_ORYSI
ID HKT21_ORYSI Reviewed; 530 AA.
AC A2YGP9; Q6TPH3; Q7GC01; Q8L6H6; Q8W1B8; Q9FPN6;
DT 11-SEP-2007, integrated into UniProtKB/Swiss-Prot.
DT 11-SEP-2007, sequence version 2.
DT 03-AUG-2022, entry version 61.
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=Po-OsHKT1 {ECO:0000303|PubMed:11489190};
GN Name=HKT2;1 {ECO:0000303|PubMed:16809061};
GN Synonyms=HKT1 {ECO:0000303|PubMed:12795699}; ORFNames=OsI_023492;
OS Oryza sativa subsp. indica (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=39946;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, AND INDUCTION.
RC STRAIN=cv. Pokkali; 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 [MRNA], FUNCTION, TISSUE SPECIFICITY, AND INDUCTION.
RC STRAIN=cv. IR29, and cv. IR36;
RX PubMed=12182709; DOI=10.1046/j.1365-313x.2002.01374.x;
RA Golldack D., Su H., Quigley F., Kamasani U.R., Munoz-Garay C., Balderas E.,
RA Popova O.V., Bennett J., Bohnert H.J., Pantoja O.;
RT "Characterization of a HKT-type transporter in rice as a general alkali
RT cation transporter.";
RL Plant J. 31:529-542(2002).
RN [3]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=cv. IR36, and cv. Pokkali;
RA Ghareyazie B., Bennett J.;
RT "Isolation of the gene encoding high-affinity sodium/potassium symporter
RT hkt1 of rice (Oryza sativa L.).";
RL Submitted (APR-2002) to the EMBL/GenBank/DDBJ databases.
RN [4]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=cv. 93-11;
RX PubMed=15685292; DOI=10.1371/journal.pbio.0030038;
RA Yu J., Wang J., Lin W., Li S., Li H., Zhou J., Ni P., Dong W., Hu S.,
RA Zeng C., Zhang J., Zhang Y., Li R., Xu Z., Li S., Li X., Zheng H., Cong L.,
RA Lin L., Yin J., Geng J., Li G., Shi J., Liu J., Lv H., Li J., Wang J.,
RA Deng Y., Ran L., Shi X., Wang X., Wu Q., Li C., Ren X., Wang J., Wang X.,
RA Li D., Liu D., Zhang X., Ji Z., Zhao W., Sun Y., Zhang Z., Bao J., Han Y.,
RA Dong L., Ji J., Chen P., Wu S., Liu J., Xiao Y., Bu D., Tan J., Yang L.,
RA Ye C., Zhang J., Xu J., Zhou Y., Yu Y., Zhang B., Zhuang S., Wei H.,
RA Liu B., Lei M., Yu H., Li Y., Xu H., Wei S., He X., Fang L., Zhang Z.,
RA Zhang Y., Huang X., Su Z., Tong W., Li J., Tong Z., Li S., Ye J., Wang L.,
RA Fang L., Lei T., Chen C.-S., Chen H.-C., Xu Z., Li H., Huang H., Zhang F.,
RA Xu H., Li N., Zhao C., Li S., Dong L., Huang Y., Li L., Xi Y., Qi Q.,
RA Li W., Zhang B., Hu W., Zhang Y., Tian X., Jiao Y., Liang X., Jin J.,
RA Gao L., Zheng W., Hao B., Liu S.-M., Wang W., Yuan L., Cao M.,
RA McDermott J., Samudrala R., Wang J., Wong G.K.-S., Yang H.;
RT "The genomes of Oryza sativa: a history of duplications.";
RL PLoS Biol. 3:266-281(2005).
RN [5]
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 [6]
RP FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, AND NOMENCLATURE.
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 [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).
CC -!- FUNCTION: Seems to be involved in regulation of potassium-sodium
CC homeostasis (PubMed:11489190, PubMed:12182709, PubMed:12795699,
CC PubMed:11959905). Seems to act as a high-affinity sodium transporter,
CC which mediates increased sodium uptake in roots under potassium
CC deficiency and contributes to sodium accumulation and salt toxicity
CC (PubMed:11489190, PubMed:12182709, PubMed:12795699, PubMed:11959905).
CC Involved in nutritional sodium uptake and distribution in potassium-
CC starved roots to allow plant growth (By similarity). May also act as a
CC potassium transporter (PubMed:11489190, PubMed:12182709,
CC PubMed:12795699, PubMed:11959905). Functions as sodium-potassium
CC cotransporter (By similarity). {ECO:0000250|UniProtKB:Q0D9S3,
CC ECO:0000269|PubMed:11489190, ECO:0000269|PubMed:11959905,
CC ECO:0000269|PubMed:12182709, ECO:0000269|PubMed:12795699}.
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:12182709,
CC ECO:0000269|PubMed:12795699};
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: Membrane {ECO:0000255}; Multi-pass membrane
CC protein {ECO:0000255}.
CC -!- TISSUE SPECIFICITY: Expressed in epidermis and vascular tissue of
CC endodermis in roots, and in cells surrounding the vasculature in
CC leaves. {ECO:0000269|PubMed:12182709}.
CC -!- INDUCTION: Induced by potassium starvation in roots. Down-regulated by
CC sodium, potassium, rubidium, lithium and cesium.
CC {ECO:0000269|PubMed:11489190, ECO:0000269|PubMed:12182709}.
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 -!- SIMILARITY: Belongs to the TrkH potassium transport family. HKT (TC
CC 2.A.38.3) subfamily. {ECO:0000305}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; AB061312; BAB61790.1; -; mRNA.
DR EMBL; AF313388; AAG37274.1; -; mRNA.
DR EMBL; AF450299; AAL48250.1; -; Transcribed_RNA.
DR EMBL; AF500082; AAM46870.1; -; Genomic_DNA.
DR EMBL; AY390528; AAQ91202.1; -; Genomic_DNA.
DR EMBL; CM000131; -; NOT_ANNOTATED_CDS; Genomic_DNA.
DR AlphaFoldDB; A2YGP9; -.
DR SMR; A2YGP9; -.
DR STRING; 39946.A2YGP9; -.
DR Proteomes; UP000007015; Chromosome 6.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0008324; F:cation transmembrane transporter activity; IEA:InterPro.
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 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_0000303670"
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 21
FT /note="R -> K (in Ref. 3; AAQ91202)"
FT /evidence="ECO:0000305"
FT CONFLICT 32
FT /note="R -> K (in Ref. 3; AAQ91202)"
FT /evidence="ECO:0000305"
FT CONFLICT 403
FT /note="D -> E (in Ref. 4; CM000131)"
FT /evidence="ECO:0000305"
FT CONFLICT 432
FT /note="V -> A (in Ref. 2; AAL48250)"
FT /evidence="ECO:0000305"
FT CONFLICT 471
FT /note="S -> T (in Ref. 4; CM000131)"
FT /evidence="ECO:0000305"
FT CONFLICT 509
FT /note="F -> S (in Ref. 4; CM000131)"
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
