HMT3_ARATH
ID HMT3_ARATH Reviewed; 347 AA.
AC Q8LAX0; Q9LUI7;
DT 19-JUL-2004, integrated into UniProtKB/Swiss-Prot.
DT 19-JUL-2004, sequence version 2.
DT 03-AUG-2022, entry version 118.
DE RecName: Full=Homocysteine S-methyltransferase 3;
DE EC=2.1.1.10;
DE AltName: Full=S-methylmethionine:homocysteine methyltransferase 3;
DE Short=AtHMT-3;
DE Short=SMM:Hcy S-methyltransferase 3;
GN Name=HMT3; OrderedLocusNames=At3g22740; ORFNames=MWI23.11;
OS Arabidopsis thaliana (Mouse-ear cress).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC rosids; malvids; Brassicales; Brassicaceae; Camelineae; Arabidopsis.
OX NCBI_TaxID=3702;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], ENZYME ACTIVITY, PROBABLE FUNCTION OF SMM
RP CYCLE, BIOPHYSICOCHEMICAL PROPERTIES, AND TISSUE SPECIFICITY.
RC STRAIN=cv. Columbia; TISSUE=Leaf;
RX PubMed=11309147; DOI=10.1046/j.1365-313x.2001.00988.x;
RA Ranocha P., McNeil S.D., Ziemak M.J., Li C., Tarczynski M.C., Hanson A.D.;
RT "The S-methylmethionine cycle in angiosperms: ubiquity, antiquity and
RT activity.";
RL Plant J. 25:575-584(2001).
RN [2]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=cv. Columbia;
RX PubMed=10819329; DOI=10.1093/dnares/7.2.131;
RA Sato S., Nakamura Y., Kaneko T., Katoh T., Asamizu E., Tabata S.;
RT "Structural analysis of Arabidopsis thaliana chromosome 3. I. Sequence
RT features of the regions of 4,504,864 bp covered by sixty P1 and TAC
RT clones.";
RL DNA Res. 7:131-135(2000).
RN [3]
RP GENOME REANNOTATION.
RC STRAIN=cv. Columbia;
RX PubMed=27862469; DOI=10.1111/tpj.13415;
RA Cheng C.Y., Krishnakumar V., Chan A.P., Thibaud-Nissen F., Schobel S.,
RA Town C.D.;
RT "Araport11: a complete reannotation of the Arabidopsis thaliana reference
RT genome.";
RL Plant J. 89:789-804(2017).
RN [4]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC STRAIN=cv. Columbia;
RX PubMed=11910074; DOI=10.1126/science.1071006;
RA Seki M., Narusaka M., Kamiya A., Ishida J., Satou M., Sakurai T.,
RA Nakajima M., Enju A., Akiyama K., Oono Y., Muramatsu M., Hayashizaki Y.,
RA Kawai J., Carninci P., Itoh M., Ishii Y., Arakawa T., Shibata K.,
RA Shinagawa A., Shinozaki K.;
RT "Functional annotation of a full-length Arabidopsis cDNA collection.";
RL Science 296:141-145(2002).
RN [5]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC STRAIN=cv. Columbia;
RX PubMed=14593172; DOI=10.1126/science.1088305;
RA Yamada K., Lim J., Dale J.M., Chen H., Shinn P., Palm C.J., Southwick A.M.,
RA Wu H.C., Kim C.J., Nguyen M., Pham P.K., Cheuk R.F., Karlin-Newmann G.,
RA Liu S.X., Lam B., Sakano H., Wu T., Yu G., Miranda M., Quach H.L.,
RA Tripp M., Chang C.H., Lee J.M., Toriumi M.J., Chan M.M., Tang C.C.,
RA Onodera C.S., Deng J.M., Akiyama K., Ansari Y., Arakawa T., Banh J.,
RA Banno F., Bowser L., Brooks S.Y., Carninci P., Chao Q., Choy N., Enju A.,
RA Goldsmith A.D., Gurjal M., Hansen N.F., Hayashizaki Y., Johnson-Hopson C.,
RA Hsuan V.W., Iida K., Karnes M., Khan S., Koesema E., Ishida J., Jiang P.X.,
RA Jones T., Kawai J., Kamiya A., Meyers C., Nakajima M., Narusaka M.,
RA Seki M., Sakurai T., Satou M., Tamse R., Vaysberg M., Wallender E.K.,
RA Wong C., Yamamura Y., Yuan S., Shinozaki K., Davis R.W., Theologis A.,
RA Ecker J.R.;
RT "Empirical analysis of transcriptional activity in the Arabidopsis
RT genome.";
RL Science 302:842-846(2003).
RN [6]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RA Brover V.V., Troukhan M.E., Alexandrov N.A., Lu Y.-P., Flavell R.B.,
RA Feldmann K.A.;
RT "Full-length cDNA from Arabidopsis thaliana.";
RL Submitted (MAR-2002) to the EMBL/GenBank/DDBJ databases.
CC -!- FUNCTION: Catalyzes methyl transfer from S-methylmethionine (SMM) to
CC adenosyl-L-homocysteine (AdoMet). SMM degradation (by HMT-1, HMT-2 and
CC HMT-3) and biosynthesis (by MMT1) constitute the SMM cycle in plants,
CC which is probably required to achieve short term control of AdoMet
CC level.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=L-homocysteine + S-methyl-L-methionine = H(+) + 2 L-
CC methionine; Xref=Rhea:RHEA:26337, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:57844, ChEBI:CHEBI:58199, ChEBI:CHEBI:58252; EC=2.1.1.10;
CC Evidence={ECO:0000269|PubMed:11309147};
CC -!- COFACTOR:
CC Name=Zn(2+); Xref=ChEBI:CHEBI:29105;
CC Evidence={ECO:0000255|PROSITE-ProRule:PRU00333};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=335 uM for S-methylmethionine {ECO:0000269|PubMed:11309147};
CC KM=1760 uM for (S,S)-AdoMet {ECO:0000269|PubMed:11309147};
CC -!- SUBUNIT: Monomer. {ECO:0000250}.
CC -!- TISSUE SPECIFICITY: Expressed predominantly in rosette leaves.
CC Expressed in roots, cauline leaves and developing seeds.
CC {ECO:0000269|PubMed:11309147}.
CC -!- MISCELLANEOUS: In contrast to HMT-1, it is not inhibited by methionine.
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DR EMBL; AF297394; AAG10301.1; -; mRNA.
DR EMBL; AB022223; BAB01249.1; -; Genomic_DNA.
DR EMBL; CP002686; AEE76672.1; -; Genomic_DNA.
DR EMBL; AK118021; BAC42654.1; -; mRNA.
DR EMBL; BT005318; AAO63382.1; -; mRNA.
DR EMBL; AY087554; AAM65096.1; -; mRNA.
DR RefSeq; NP_566715.1; NM_113173.3.
DR AlphaFoldDB; Q8LAX0; -.
DR SMR; Q8LAX0; -.
DR STRING; 3702.AT3G22740.1; -.
DR PaxDb; Q8LAX0; -.
DR PRIDE; Q8LAX0; -.
DR ProteomicsDB; 230213; -.
DR EnsemblPlants; AT3G22740.1; AT3G22740.1; AT3G22740.
DR GeneID; 821845; -.
DR Gramene; AT3G22740.1; AT3G22740.1; AT3G22740.
DR KEGG; ath:AT3G22740; -.
DR Araport; AT3G22740; -.
DR TAIR; locus:2094419; AT3G22740.
DR eggNOG; KOG1579; Eukaryota.
DR HOGENOM; CLU_004914_3_2_1; -.
DR InParanoid; Q8LAX0; -.
DR OMA; YIGGCCK; -.
DR OrthoDB; 731388at2759; -.
DR PhylomeDB; Q8LAX0; -.
DR BioCyc; ARA:AT3G22740-MON; -.
DR BioCyc; MetaCyc:AT3G22740-MON; -.
DR BRENDA; 2.1.1.10; 399.
DR SABIO-RK; Q8LAX0; -.
DR PRO; PR:Q8LAX0; -.
DR Proteomes; UP000006548; Chromosome 3.
DR ExpressionAtlas; Q8LAX0; baseline and differential.
DR Genevisible; Q8LAX0; AT.
DR GO; GO:0047150; F:betaine-homocysteine S-methyltransferase activity; IEA:InterPro.
DR GO; GO:0008898; F:S-adenosylmethionine-homocysteine S-methyltransferase activity; IBA:GO_Central.
DR GO; GO:0061627; F:S-methylmethionine-homocysteine S-methyltransferase activity; IEA:RHEA.
DR GO; GO:0008270; F:zinc ion binding; IEA:InterPro.
DR GO; GO:0009086; P:methionine biosynthetic process; IBA:GO_Central.
DR GO; GO:0032259; P:methylation; IEA:UniProtKB-KW.
DR GO; GO:0033528; P:S-methylmethionine cycle; IBA:GO_Central.
DR Gene3D; 3.20.20.330; -; 1.
DR InterPro; IPR017226; Betaine-hCys_S-MeTrfase_BHMT.
DR InterPro; IPR003726; HCY_dom.
DR InterPro; IPR036589; HCY_dom_sf.
DR Pfam; PF02574; S-methyl_trans; 1.
DR PIRSF; PIRSF037505; Betaine_HMT; 1.
DR SUPFAM; SSF82282; SSF82282; 1.
DR PROSITE; PS50970; HCY; 1.
PE 1: Evidence at protein level;
KW Amino-acid biosynthesis; Metal-binding; Methionine biosynthesis;
KW Methyltransferase; Reference proteome; S-adenosyl-L-methionine;
KW Transferase; Zinc.
FT CHAIN 1..347
FT /note="Homocysteine S-methyltransferase 3"
FT /id="PRO_0000114613"
FT DOMAIN 12..333
FT /note="Hcy-binding"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00333"
FT BINDING 251
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00333"
FT BINDING 318
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00333"
FT BINDING 319
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00333"
FT CONFLICT 24
FT /note="A -> E (in Ref. 6; AAM65096)"
FT /evidence="ECO:0000305"
FT CONFLICT 45
FT /note="L -> I (in Ref. 6; AAM65096)"
FT /evidence="ECO:0000305"
FT CONFLICT 117
FT /note="C -> W (in Ref. 6; AAM65096)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 347 AA; 37882 MW; 45CDC34973F820CC CRC64;
MGSFVKEETS SLMTDFLEKC GGYAVVDGGF ATELQRHGAD INDPLWSAKC LITSPHLVTK
VHLDYLESGA NIIITASYQA TIQGFVAKGL SVGEAENLLR RSVEITYEAR EIFYNRCTKG
SWDFAYAGKA SRRPILVAAS VGSYGAYLAD GSEYSGIYGD SVSKETLKDF HRRRVQILAK
SGADLIAFET IPNKLEAEAY ADLLEEEDID IPAWFSFTSK DGVSVPRGDS VVECAKVADS
CKNVVAIGIN CTAPRYIHAL IISLRQMTRK PIVVYPNSGE VYDGLNKKWI KSEGESEEDF
VSYVSKWRDA GASLFGGCCR TTPNTIRAIA KVLSDEPSAA SKPKFGQ