SMO12_ARATH
ID SMO12_ARATH Reviewed; 299 AA.
AC Q1EC69; Q8GT72; Q8LAD9;
DT 19-OCT-2011, integrated into UniProtKB/Swiss-Prot.
DT 11-JUL-2006, sequence version 1.
DT 03-AUG-2022, entry version 112.
DE RecName: Full=Methylsterol monooxygenase 1-2 {ECO:0000303|PubMed:14653780};
DE EC=1.14.18.10 {ECO:0000250|UniProtKB:Q8L7W5};
DE EC=1.14.18.9 {ECO:0000250|UniProtKB:Q8L7W5};
DE AltName: Full=Sterol 4-alpha-methyl-oxidase 1-2 {ECO:0000303|PubMed:14653780};
DE Short=AtSMO1-2 {ECO:0000303|PubMed:14653780};
GN Name=SMO1-2 {ECO:0000303|PubMed:14653780};
GN OrderedLocusNames=At4g22756 {ECO:0000312|Araport:AT4G22756};
GN ORFNames=T12H17 {ECO:0000312|EMBL:AL021635};
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], GENE FAMILY, AND NOMENCLATURE.
RC STRAIN=cv. Columbia; TISSUE=Silique;
RX PubMed=14653780; DOI=10.1042/bj20031572;
RA Darnet S., Rahier A.;
RT "Plant sterol biosynthesis: identification of two distinct families of
RT sterol 4alpha-methyl oxidases.";
RL Biochem. J. 378:889-898(2004).
RN [2]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=cv. Columbia;
RX PubMed=10617198; DOI=10.1038/47134;
RA Mayer K.F.X., Schueller C., Wambutt R., Murphy G., Volckaert G., Pohl T.,
RA Duesterhoeft A., Stiekema W., Entian K.-D., Terryn N., Harris B.,
RA Ansorge W., Brandt P., Grivell L.A., Rieger M., Weichselgartner M.,
RA de Simone V., Obermaier B., Mache R., Mueller M., Kreis M., Delseny M.,
RA Puigdomenech P., Watson M., Schmidtheini T., Reichert B., Portetelle D.,
RA Perez-Alonso M., Boutry M., Bancroft I., Vos P., Hoheisel J.,
RA Zimmermann W., Wedler H., Ridley P., Langham S.-A., McCullagh B.,
RA Bilham L., Robben J., van der Schueren J., Grymonprez B., Chuang Y.-J.,
RA Vandenbussche F., Braeken M., Weltjens I., Voet M., Bastiaens I., Aert R.,
RA Defoor E., Weitzenegger T., Bothe G., Ramsperger U., Hilbert H., Braun M.,
RA Holzer E., Brandt A., Peters S., van Staveren M., Dirkse W., Mooijman P.,
RA Klein Lankhorst R., Rose M., Hauf J., Koetter P., Berneiser S., Hempel S.,
RA Feldpausch M., Lamberth S., Van den Daele H., De Keyser A., Buysshaert C.,
RA Gielen J., Villarroel R., De Clercq R., van Montagu M., Rogers J.,
RA Cronin A., Quail M.A., Bray-Allen S., Clark L., Doggett J., Hall S.,
RA Kay M., Lennard N., McLay K., Mayes R., Pettett A., Rajandream M.A.,
RA Lyne M., Benes V., Rechmann S., Borkova D., Bloecker H., Scharfe M.,
RA Grimm M., Loehnert T.-H., Dose S., de Haan M., Maarse A.C., Schaefer M.,
RA Mueller-Auer S., Gabel C., Fuchs M., Fartmann B., Granderath K., Dauner D.,
RA Herzl A., Neumann S., Argiriou A., Vitale D., Liguori R., Piravandi E.,
RA Massenet O., Quigley F., Clabauld G., Muendlein A., Felber R., Schnabl S.,
RA Hiller R., Schmidt W., Lecharny A., Aubourg S., Chefdor F., Cooke R.,
RA Berger C., Monfort A., Casacuberta E., Gibbons T., Weber N., Vandenbol M.,
RA Bargues M., Terol J., Torres A., Perez-Perez A., Purnelle B., Bent E.,
RA Johnson S., Tacon D., Jesse T., Heijnen L., Schwarz S., Scholler P.,
RA Heber S., Francs P., Bielke C., Frishman D., Haase D., Lemcke K.,
RA Mewes H.-W., Stocker S., Zaccaria P., Bevan M., Wilson R.K.,
RA de la Bastide M., Habermann K., Parnell L., Dedhia N., Gnoj L., Schutz K.,
RA Huang E., Spiegel L., Sekhon M., Murray J., Sheet P., Cordes M.,
RA Abu-Threideh J., Stoneking T., Kalicki J., Graves T., Harmon G.,
RA Edwards J., Latreille P., Courtney L., Cloud J., Abbott A., Scott K.,
RA Johnson D., Minx P., Bentley D., Fulton B., Miller N., Greco T., Kemp K.,
RA Kramer J., Fulton L., Mardis E., Dante M., Pepin K., Hillier L.W.,
RA Nelson J., Spieth J., Ryan E., Andrews S., Geisel C., Layman D., Du H.,
RA Ali J., Berghoff A., Jones K., Drone K., Cotton M., Joshu C., Antonoiu B.,
RA Zidanic M., Strong C., Sun H., Lamar B., Yordan C., Ma P., Zhong J.,
RA Preston R., Vil D., Shekher M., Matero A., Shah R., Swaby I.K.,
RA O'Shaughnessy A., Rodriguez M., Hoffman J., Till S., Granat S., Shohdy N.,
RA Hasegawa A., Hameed A., Lodhi M., Johnson A., Chen E., Marra M.A.,
RA Martienssen R., McCombie W.R.;
RT "Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana.";
RL Nature 402:769-777(1999).
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].
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.
RN [5]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC STRAIN=cv. Columbia;
RA Quinitio C., Chen H., Kim C.J., Shinn P., Ecker J.R.;
RT "Arabidopsis ORF clones.";
RL Submitted (JUN-2006) to the EMBL/GenBank/DDBJ databases.
RN [6]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC STRAIN=cv. Columbia;
RA Totoki Y., Seki M., Ishida J., Nakajima M., Enju A., Kamiya A.,
RA Narusaka M., Shin-i T., Nakagawa M., Sakamoto N., Oishi K., Kohara Y.,
RA Kobayashi M., Toyoda A., Sakaki Y., Sakurai T., Iida K., Akiyama K.,
RA Satou M., Toyoda T., Konagaya A., Carninci P., Kawai J., Hayashizaki Y.,
RA Shinozaki K.;
RT "Large-scale analysis of RIKEN Arabidopsis full-length (RAFL) cDNAs.";
RL Submitted (JUL-2006) to the EMBL/GenBank/DDBJ databases.
RN [7]
RP FUNCTION, DISRUPTION PHENOTYPE, INTERACTION WITH ACBP1, TISSUE SPECIFICITY,
RP SUBCELLULAR LOCATION, AND DEVELOPMENTAL STAGE.
RC STRAIN=cv. Columbia;
RX PubMed=29288621; DOI=10.1111/nph.14965;
RA Lung S.-C., Liao P., Yeung E.C., Hsiao A.-S., Xue Y., Chye M.-L.;
RT "Arabidopsis ACYL-COA-BINDING PROTEIN1 interacts with STEROL C4-METHYL
RT OXIDASE1-2 to modulate gene expression of homeodomain-leucine zipper IV
RT transcription factors.";
RL New Phytol. 218:183-200(2018).
RN [8]
RP FUNCTION, DISRUPTION PHENOTYPE, SUBCELLULAR LOCATION, TISSUE SPECIFICITY,
RP AND DEVELOPMENTAL STAGE.
RC STRAIN=cv. Columbia, cv. Landsberg erecta, and cv. Wassilewskija;
RX PubMed=31341004; DOI=10.1104/pp.19.00144;
RA Song J., Sun S., Ren H., Grison M., Boutte Y., Bai W., Men S.;
RT "The SMO1 family of sterol 4alpha-methyl oxidases is essential for
RT auxin- and cytokinin-regulated embryogenesis.";
RL Plant Physiol. 181:578-594(2019).
CC -!- FUNCTION: Non-heme iron oxygenase involved in sterols biosynthesis by
CC catalyzing the removal of the first methyl group at the C-4 position
CC (By similarity). 4,4-dimethyl-9-beta,19-cyclopropylsterols such as 24-
CC methylenecycloartanol are the preferred substrates (By similarity).
CC Acts as a rate-limiting enzyme in the sterol pathway via interaction
CC with ACBP1; sterols serve as lipid modulators for gene expression of
CC homeodomain-leucine zipper IV transcription factors (PubMed:29288621).
CC Together with SMO1-1, involved in the maintenance of sterol composition
CC to balance auxin and cytokinin activities during embryogenesis
CC (PubMed:31341004). {ECO:0000250|UniProtKB:Q8L7W5,
CC ECO:0000269|PubMed:29288621, ECO:0000269|PubMed:31341004}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=4,4-dimethyl-5alpha-cholest-7-en-3beta-ol + 6 Fe(II)-
CC [cytochrome b5] + 5 H(+) + 3 O2 = 4alpha-carboxy-4beta-methyl-5alpha-
CC cholest-7-ene-3beta-ol + 6 Fe(III)-[cytochrome b5] + 4 H2O;
CC Xref=Rhea:RHEA:55220, Rhea:RHEA-COMP:10438, Rhea:RHEA-COMP:10439,
CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379,
CC ChEBI:CHEBI:16455, ChEBI:CHEBI:29033, ChEBI:CHEBI:29034,
CC ChEBI:CHEBI:58387; EC=1.14.18.9;
CC Evidence={ECO:0000250|UniProtKB:Q8L7W5};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=24-methylenecycloartanol + 6 Fe(II)-[cytochrome b5] + 5 H(+) +
CC 3 O2 = 4alpha-carboxy-4beta,14alpha-dimethyl-9beta,19-cyclo-5alpha-
CC ergost-24(24(1))-en-3beta-ol + 6 Fe(III)-[cytochrome b5] + 4 H2O;
CC Xref=Rhea:RHEA:58832, Rhea:RHEA-COMP:10438, Rhea:RHEA-COMP:10439,
CC ChEBI:CHEBI:1307, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:15379, ChEBI:CHEBI:29033, ChEBI:CHEBI:29034,
CC ChEBI:CHEBI:142916; EC=1.14.18.10;
CC Evidence={ECO:0000250|UniProtKB:Q8L7W5};
CC -!- COFACTOR:
CC Name=Fe cation; Xref=ChEBI:CHEBI:24875;
CC Evidence={ECO:0000250|UniProtKB:P53045};
CC -!- SUBUNIT: Interacts with ACBP1. {ECO:0000269|PubMed:29288621}.
CC -!- SUBCELLULAR LOCATION: Endoplasmic reticulum membrane
CC {ECO:0000269|PubMed:29288621, ECO:0000269|PubMed:31341004}; Multi-pass
CC membrane protein {ECO:0000255}.
CC -!- TISSUE SPECIFICITY: Expressed in embryo sacs, pollen and trichomes
CC (PubMed:29288621). Observed in leaves, roots, siliques and flowers
CC (PubMed:31341004). {ECO:0000269|PubMed:29288621,
CC ECO:0000269|PubMed:31341004}.
CC -!- DEVELOPMENTAL STAGE: Highly expressed in pollen grains at all floral
CC stages and in pollen tubes at anthesis (PubMed:29288621). Observed in
CC transmitting tracts along pistils, nectaries and ovules, and in the
CC entire pistils at anthesis (PubMed:29288621). In anthers, present in
CC pollen and tapetal cells (PubMed:29288621). Accumulates in imbibed
CC pollen grains and in germinating pollen tubes (PubMed:29288621).
CC Detected in embryo sacs at stages 13-14 (PubMed:29288621). During
CC embryogenesis, expressed from the globular stage to the mature stage in
CC the embryo but not in the endosperm, especially in the embryonic root
CC meristem (PubMed:31341004). Accumulates also in trichomes on rosettes
CC and stems, and the vasculature in roots (PubMed:29288621). In
CC developing seeds, expressed in the basal suspensor cells and chalazal
CC seed coat at the heart stage of embryogenesis, and in the radicle and
CC cotyledons of mature green embryos (PubMed:29288621). In leaves,
CC strongly expressed in vascular tissues (PubMed:31341004). In roots,
CC detected in root tips, mostly in the root stem cell niche and columella
CC cells (PubMed:31341004). In flowers, accumulates in styles, petals and
CC anther filaments (PubMed:31341004). In siliques, present in funiculi
CC (PubMed:31341004). {ECO:0000269|PubMed:29288621,
CC ECO:0000269|PubMed:31341004}.
CC -!- DOMAIN: The histidine box domains may contain the active site and/or be
CC involved in metal ion binding. {ECO:0000250|UniProtKB:P53045}.
CC -!- DISRUPTION PHENOTYPE: Double mutants lacking SMO1-2 and ACBP1 are
CC impaired in seed development, embryo sac development, male and female
CC gamete transmission, and pollen function, as well as altered fatty
CC acids (FAs) and sterols profiles (PubMed:29288621). The double mutant
CC smo1-1 smo1-2, which accumulates dramatically 4,4-dimethylsterols, is
CC embryo lethal, with embryo exhibiting severe defects, including no
CC cotyledon or shoot apical meristem formation, abnormal division of
CC suspensor cells, and twin embryos, and is associated with an altered
CC auxin and cytokinin homeostasis (PubMed:31341004).
CC {ECO:0000269|PubMed:29288621, ECO:0000269|PubMed:31341004}.
CC -!- MISCELLANEOUS: Requires a membrane-bound cytochrome b5 as an obligatory
CC electron carrier from NAD(P)H to SMO. {ECO:0000305}.
CC -!- SIMILARITY: Belongs to the sterol desaturase family. {ECO:0000305}.
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DR EMBL; AY035393; AAK61361.1; -; mRNA.
DR EMBL; AL021635; -; NOT_ANNOTATED_CDS; Genomic_DNA.
DR EMBL; CP002687; AEE84653.1; -; Genomic_DNA.
DR EMBL; AY087876; AAM65428.1; -; mRNA.
DR EMBL; BT025865; ABF85767.1; -; mRNA.
DR EMBL; AK229338; BAF01201.1; -; mRNA.
DR RefSeq; NP_567670.1; NM_118404.5.
DR AlphaFoldDB; Q1EC69; -.
DR BioGRID; 13663; 17.
DR IntAct; Q1EC69; 17.
DR STRING; 3702.AT4G22756.1; -.
DR PaxDb; Q1EC69; -.
DR PRIDE; Q1EC69; -.
DR ProteomicsDB; 234473; -.
DR EnsemblPlants; AT4G22756.1; AT4G22756.1; AT4G22756.
DR GeneID; 828374; -.
DR Gramene; AT4G22756.1; AT4G22756.1; AT4G22756.
DR KEGG; ath:AT4G22756; -.
DR Araport; AT4G22756; -.
DR TAIR; locus:505006515; AT4G22756.
DR eggNOG; KOG0873; Eukaryota.
DR HOGENOM; CLU_047036_5_3_1; -.
DR InParanoid; Q1EC69; -.
DR OMA; CDIMGDR; -.
DR OrthoDB; 1493916at2759; -.
DR PhylomeDB; Q1EC69; -.
DR BioCyc; ARA:AT4G22756-MON; -.
DR BioCyc; MetaCyc:AT4G22756-MON; -.
DR BRENDA; 1.14.18.10; 399.
DR PRO; PR:Q1EC69; -.
DR Proteomes; UP000006548; Chromosome 4.
DR ExpressionAtlas; Q1EC69; baseline and differential.
DR Genevisible; Q1EC69; AT.
DR GO; GO:0005783; C:endoplasmic reticulum; IDA:UniProtKB.
DR GO; GO:0005789; C:endoplasmic reticulum membrane; IBA:GO_Central.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0016020; C:membrane; IBA:GO_Central.
DR GO; GO:0000254; F:C-4 methylsterol oxidase activity; IMP:TAIR.
DR GO; GO:0005506; F:iron ion binding; IEA:InterPro.
DR GO; GO:0016491; F:oxidoreductase activity; IBA:GO_Central.
DR GO; GO:0080064; P:4,4-dimethyl-9beta,19-cyclopropylsterol oxidation; NAS:TAIR.
DR GO; GO:0055089; P:fatty acid homeostasis; IMP:UniProtKB.
DR GO; GO:0016126; P:sterol biosynthetic process; IMP:TAIR.
DR GO; GO:0055092; P:sterol homeostasis; IMP:UniProtKB.
DR InterPro; IPR006694; Fatty_acid_hydroxylase.
DR Pfam; PF04116; FA_hydroxylase; 1.
PE 1: Evidence at protein level;
KW Endoplasmic reticulum; Iron; Lipid biosynthesis; Lipid metabolism;
KW Membrane; Monooxygenase; Oxidoreductase; Reference proteome;
KW Steroid biosynthesis; Steroid metabolism; Sterol biosynthesis;
KW Sterol metabolism; Transmembrane; Transmembrane helix.
FT CHAIN 1..299
FT /note="Methylsterol monooxygenase 1-2"
FT /id="PRO_0000413162"
FT TRANSMEM 39..59
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 96..116
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 118..138
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 189..209
FT /note="Helical"
FT /evidence="ECO:0000255"
FT DOMAIN 132..267
FT /note="Fatty acid hydroxylase"
FT /evidence="ECO:0000255"
FT MOTIF 147..151
FT /note="Histidine box-1"
FT /evidence="ECO:0000250|UniProtKB:P53045"
FT MOTIF 160..164
FT /note="Histidine box-2"
FT /evidence="ECO:0000250|UniProtKB:P53045"
FT MOTIF 239..245
FT /note="Histidine box-3"
FT /evidence="ECO:0000250|UniProtKB:P53045"
FT CONFLICT 58..62
FT /note="FIESS -> LIESA (in Ref. 4; AAM65428)"
FT /evidence="ECO:0000305"
FT CONFLICT 86
FT /note="F -> L (in Ref. 4; AAM65428)"
FT /evidence="ECO:0000305"
FT CONFLICT 96
FT /note="F -> S (in Ref. 1; AAK61361)"
FT /evidence="ECO:0000305"
FT CONFLICT 132
FT /note="L -> F (in Ref. 4; AAM65428)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 299 AA; 34989 MW; 803E51A0C3E1FACD CRC64;
MIPYATIEEA SIALSRNLTW LETLWFDYSA TKSDYYLYCH NILFLFLIFS LVPLPLVFIE
SSQSTSDLFN RYKIQPKVKN SFSSMFKCYK DVMKMFILVV GPLQLVSYPS IQMIEIRSGL
PLPSCMEIVA QLVVYFLVED YTNYWVHRFF HCKWGYEKFH HIHHEYTAPI GYAAPYAHWA
EVLLLGIPTF LGPAIAPGHM ITFWLWIALR QIEAIETHSG YDFPWSLTKY IPFYGGAEYH
DYHHYVGGQS QSNFASVFTY CDYIYGTDKG YRFQKKLLQQ MKEKSKKSNK LVNGGEKFD
