ID HMOX1_ARATH Reviewed; 282 AA. AC O48782; B3H4A6; Q7E9A5; Q9FPE3; DT 27-JUL-2011, integrated into UniProtKB/Swiss-Prot. DT 01-NOV-1999, sequence version 2. DT 24-JAN-2024, entry version 146. DE RecName: Full=Heme oxygenase 1, chloroplastic; DE Short=AtHO1; DE EC=1.14.14.18 {ECO:0000269|PubMed:10072395, ECO:0000269|PubMed:12481078}; DE AltName: Full=Protein GENOMES UNCOUPLED 2; DE AltName: Full=Protein REVERSAL OF THE DET PHENOTYPE 4; DE Flags: Precursor; GN Name=HO1; Synonyms=GUN2, HY1, HY6, TED4; OrderedLocusNames=At2g26670; GN ORFNames=F18A8.4; 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 [GENOMIC DNA / MRNA] (ISOFORM 1), FUNCTION, CATALYTIC RP ACTIVITY, SUBCELLULAR LOCATION, AND DISRUPTION PHENOTYPE. RC STRAIN=cv. Landsberg erecta; RX PubMed=10072395; DOI=10.1105/tpc.11.3.335; RA Muramoto T., Kohchi T., Yokota A., Hwang I., Goodman H.M.; RT "The Arabidopsis photomorphogenic mutant hy1 is deficient in phytochrome RT chromophore biosynthesis as a result of a mutation in a plastid heme RT oxygenase."; RL Plant Cell 11:335-348(1999). RN [2] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, TISSUE SPECIFICITY, AND RP DISRUPTION PHENOTYPE. RC STRAIN=cv. Columbia, and cv. Landsberg erecta; RX PubMed=10339624; DOI=10.1073/pnas.96.11.6541; RA Davis S.J., Kurepa J., Vierstra R.D.; RT "The Arabidopsis thaliana HY1 locus, required for phytochrome-chromophore RT biosynthesis, encodes a protein related to heme oxygenases."; RL Proc. Natl. Acad. Sci. U.S.A. 96:6541-6546(1999). RN [3] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=cv. Columbia; RX PubMed=10617197; DOI=10.1038/45471; RA Lin X., Kaul S., Rounsley S.D., Shea T.P., Benito M.-I., Town C.D., RA Fujii C.Y., Mason T.M., Bowman C.L., Barnstead M.E., Feldblyum T.V., RA Buell C.R., Ketchum K.A., Lee J.J., Ronning C.M., Koo H.L., Moffat K.S., RA Cronin L.A., Shen M., Pai G., Van Aken S., Umayam L., Tallon L.J., RA Gill J.E., Adams M.D., Carrera A.J., Creasy T.H., Goodman H.M., RA Somerville C.R., Copenhaver G.P., Preuss D., Nierman W.C., White O., RA Eisen J.A., Salzberg S.L., Fraser C.M., Venter J.C.; RT "Sequence and analysis of chromosome 2 of the plant Arabidopsis thaliana."; RL Nature 402:761-768(1999). RN [4] 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 [5] RP NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1). 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] (ISOFORM 1). 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 [7] RP DISRUPTION PHENOTYPE. RX PubMed=12359912; DOI=10.1105/tpc.1.9.867; RA Chory J., Peto C.A., Ashbaugh M., Saganich R., Pratt L., Ausubel F.; RT "Different roles for phytochrome in etiolated and green plants deduced from RT characterization of Arabidopsis thaliana mutants."; RL Plant Cell 1:867-880(1989). RN [8] RP FUNCTION, AND DISRUPTION PHENOTYPE. RX PubMed=12324588; DOI=10.1105/tpc.3.11.1177; RA Parks B.M., Quail P.H.; RT "Phytochrome-deficient hy1 and hy2 long hypocotyl mutants of Arabidopsis RT are defective in phytochrome chromophore biosynthesis."; RL Plant Cell 3:1177-1186(1991). RN [9] RP FUNCTION, AND DISRUPTION PHENOTYPE. RX PubMed=7690685; DOI=10.1016/0092-8674(93)90459-4; RA Susek R.E., Ausubel F.M., Chory J.; RT "Signal transduction mutants of Arabidopsis uncouple nuclear CAB and RBCS RT gene expression from chloroplast development."; RL Cell 74:787-799(1993). RN [10] RP FUNCTION, AND DISRUPTION PHENOTYPE. RX PubMed=12232145; DOI=10.1104/pp.104.3.1027; RA Neff M.M., Van Volkenburgh E.; RT "Light-stimulated cotyledon expansion in Arabidopsis seedlings (the role of RT phytochrome b)."; RL Plant Physiol. 104:1027-1032(1994). RN [11] RP FUNCTION, AND DISRUPTION PHENOTYPE. RX PubMed=11135121; DOI=10.1046/j.1365-313x.2000.00936.x; RA Vinti G., Hills A., Campbell S., Bowyer J.R., Mochizuki N., Chory J., RA Lopez-Juez E.; RT "Interactions between hy1 and gun mutants of Arabidopsis, and their RT implications for plastid/nuclear signalling."; RL Plant J. 24:883-894(2000). RN [12] RP FUNCTION. RX PubMed=11172074; DOI=10.1073/pnas.98.4.2053; RA Mochizuki N., Brusslan J.A., Larkin R., Nagatani A., Chory J.; RT "Arabidopsis genomes uncoupled 5 (GUN5) mutant reveals the involvement of RT Mg-chelatase H subunit in plastid-to-nucleus signal transduction."; RL Proc. Natl. Acad. Sci. U.S.A. 98:2053-2058(2001). RN [13] RP FUNCTION, CATALYTIC ACTIVITY, ACTIVITY REGULATION, AND BIOPHYSICOCHEMICAL RP PROPERTIES. RX PubMed=12481078; DOI=10.1104/pp.008128; RA Muramoto T., Tsurui N., Terry M.J., Yokota A., Kohchi T.; RT "Expression and biochemical properties of a ferredoxin-dependent heme RT oxygenase required for phytochrome chromophore synthesis."; RL Plant Physiol. 130:1958-1966(2002). RN [14] RP FUNCTION, TISSUE SPECIFICITY, AND DISRUPTION PHENOTYPE. RX PubMed=16428602; DOI=10.1104/pp.105.074211; RA Emborg T.J., Walker J.M., Noh B., Vierstra R.D.; RT "Multiple heme oxygenase family members contribute to the biosynthesis of RT the phytochrome chromophore in Arabidopsis."; RL Plant Physiol. 140:856-868(2006). RN [15] RP INDUCTION, AND DISRUPTION PHENOTYPE. RX PubMed=17567636; DOI=10.1093/pcp/pcm076; RA Zhai Q., Li C.B., Zheng W., Wu X., Zhao J., Zhou G., Jiang H., Sun J., RA Lou Y., Li C.; RT "Phytochrome chromophore deficiency leads to overproduction of jasmonic RT acid and elevated expression of jasmonate-responsive genes in RT Arabidopsis."; RL Plant Cell Physiol. 48:1061-1071(2007). RN [16] RP FUNCTION, SUBCELLULAR LOCATION, AND BIOPHYSICOCHEMICAL PROPERTIES. RX PubMed=19860740; DOI=10.1042/bj20090775; RA Gisk B., Yasui Y., Kohchi T., Frankenberg-Dinkel N.; RT "Characterization of the haem oxygenase protein family in Arabidopsis RT thaliana reveals a diversity of functions."; RL Biochem. J. 425:425-434(2010). RN [17] RP FUNCTION, TISSUE SPECIFICITY, INDUCTION, AND DISRUPTION PHENOTYPE. RX PubMed=20979354; DOI=10.1021/bi1014369; RA Gisk B., Bregier F., Krueger R.A., Broering M., Frankenberg-Dinkel N.; RT "Enzymatic ring opening of an iron corrole by plant-type heme oxygenases: RT unexpected substrate and protein selectivities."; RL Biochemistry 49:10042-10044(2010). RN [18] RP FUNCTION, AND DISRUPTION PHENOTYPE. RX PubMed=21205037; DOI=10.1111/j.1365-313x.2011.04488.x; RA Xie Y.J., Xu S., Han B., Wu M.Z., Yuan X.X., Han Y., Gu Q., Xu D.K., RA Yang Q., Shen W.B.; RT "Evidence of Arabidopsis salt acclimation induced by up-regulation of HY1 RT and the regulatory role of RbohD-derived reactive oxygen species RT synthesis."; RL Plant J. 66:280-292(2011). CC -!- FUNCTION: Key enzyme in the synthesis of the chromophore of the CC phytochrome family of plant photoreceptors. Catalyzes the opening of CC the heme ring to form the open-chain tetrapyrrole biliverdin IX with CC the release of iron and carbon monoxide (CO). Produces specifically the CC biliverdin IX-alpha isomer. Can form complex with heme, is ferredoxin- CC dependent and its activity is increased in the presence of ascorbate. CC Plays a role in salt acclimation signaling. May affect the plastid-to- CC nucleus signaling pathway by perturbing tetrapyrrole synthesis. The CC plastid-to-nucleus signal plays an important role in the coordinated CC expression of both nuclear- and chloroplast-localized genes that encode CC photosynthesis-related proteins. {ECO:0000269|PubMed:10072395, CC ECO:0000269|PubMed:10339624, ECO:0000269|PubMed:11135121, CC ECO:0000269|PubMed:11172074, ECO:0000269|PubMed:12232145, CC ECO:0000269|PubMed:12324588, ECO:0000269|PubMed:12481078, CC ECO:0000269|PubMed:16428602, ECO:0000269|PubMed:19860740, CC ECO:0000269|PubMed:20979354, ECO:0000269|PubMed:21205037, CC ECO:0000269|PubMed:7690685}. CC -!- CATALYTIC ACTIVITY: CC Reaction=heme b + 3 O2 + 3 reduced [NADPH--hemoprotein reductase] = CC biliverdin IXalpha + CO + Fe(2+) + H(+) + 3 H2O + 3 oxidized CC [NADPH--hemoprotein reductase]; Xref=Rhea:RHEA:21764, Rhea:RHEA- CC COMP:11964, Rhea:RHEA-COMP:11965, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:17245, CC ChEBI:CHEBI:29033, ChEBI:CHEBI:57618, ChEBI:CHEBI:57991, CC ChEBI:CHEBI:58210, ChEBI:CHEBI:60344; EC=1.14.14.18; CC Evidence={ECO:0000269|PubMed:10072395, ECO:0000269|PubMed:12481078}; CC -!- ACTIVITY REGULATION: Activated by ascorbate. CC {ECO:0000269|PubMed:12481078}. CC -!- BIOPHYSICOCHEMICAL PROPERTIES: CC Kinetic parameters: CC KM=1.3 uM for hemin {ECO:0000269|PubMed:12481078, CC ECO:0000269|PubMed:19860740}; CC KM=1.9 uM for ferredoxin {ECO:0000269|PubMed:12481078, CC ECO:0000269|PubMed:19860740}; CC KM=420 uM for ascorbate {ECO:0000269|PubMed:12481078, CC ECO:0000269|PubMed:19860740}; CC pH dependence: CC Optimum pH is 7.2. {ECO:0000269|PubMed:12481078, CC ECO:0000269|PubMed:19860740}; CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast CC {ECO:0000269|PubMed:10072395, ECO:0000269|PubMed:19860740}. CC -!- ALTERNATIVE PRODUCTS: CC Event=Alternative splicing; Named isoforms=2; CC Name=1; CC IsoId=O48782-1; Sequence=Displayed; CC Name=2; CC IsoId=O48782-2; Sequence=VSP_041652; CC -!- TISSUE SPECIFICITY: Widely expressed. {ECO:0000269|PubMed:10339624, CC ECO:0000269|PubMed:16428602, ECO:0000269|PubMed:20979354}. CC -!- INDUCTION: By salt treatment. Down-regulated by jasmonate. CC {ECO:0000269|PubMed:17567636, ECO:0000269|PubMed:20979354}. CC -!- DISRUPTION PHENOTYPE: Long hypocotyl, incomplete chloroplast and leaf CC development, lack of photoreversible phytochromes and lack of CC phytochromobilin, the phytochrome chromophore. No cotyledon expansion CC in response to bright-red light. Increased levels of jasmonate (JA) and CC constitutive expression of JA-inducible defense genes. Increased CC sensitivity to salt stress and no acclimation response to salinity. CC {ECO:0000269|PubMed:10072395, ECO:0000269|PubMed:10339624, CC ECO:0000269|PubMed:11135121, ECO:0000269|PubMed:12232145, CC ECO:0000269|PubMed:12324588, ECO:0000269|PubMed:12359912, CC ECO:0000269|PubMed:16428602, ECO:0000269|PubMed:17567636, CC ECO:0000269|PubMed:20979354, ECO:0000269|PubMed:21205037, CC ECO:0000269|PubMed:7690685}. CC -!- SIMILARITY: Belongs to the heme oxygenase family. {ECO:0000305}. CC -!- SEQUENCE CAUTION: CC Sequence=AAK52998.1; Type=Erroneous initiation; Note=Truncated N-terminus.; Evidence={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; AB021857; BAA77758.1; -; Genomic_DNA. DR EMBL; AB021858; BAA77759.1; -; mRNA. DR EMBL; AF132475; AAD22107.1; -; Genomic_DNA. DR EMBL; AF132476; AAD22108.1; -; Genomic_DNA. DR EMBL; AC003105; AAB95301.2; -; Genomic_DNA. DR EMBL; CP002685; AEC07872.1; -; Genomic_DNA. DR EMBL; CP002685; AEC07873.1; -; Genomic_DNA. DR EMBL; AF327418; AAG42008.2; -; mRNA. DR EMBL; AF375414; AAK52998.1; ALT_INIT; mRNA. DR EMBL; AY129477; AAM91063.1; -; mRNA. DR EMBL; BT002327; AAN86160.1; -; mRNA. DR EMBL; AY087288; AAM64841.1; -; mRNA. DR PIR; T52457; T52457. DR RefSeq; NP_001118392.1; NM_001124920.1. [O48782-2] DR RefSeq; NP_180235.1; NM_128224.3. [O48782-1] DR PDB; 7EQH; X-ray; 2.20 A; A/B=55-282. DR PDBsum; 7EQH; -. DR AlphaFoldDB; O48782; -. DR SMR; O48782; -. DR BioGRID; 2560; 1. DR STRING; 3702.O48782; -. DR iPTMnet; O48782; -. DR PaxDb; 3702-AT2G26670-1; -. DR ProteomicsDB; 232086; -. [O48782-1] DR EnsemblPlants; AT2G26670.1; AT2G26670.1; AT2G26670. [O48782-1] DR EnsemblPlants; AT2G26670.2; AT2G26670.2; AT2G26670. [O48782-2] DR GeneID; 817208; -. DR Gramene; AT2G26670.1; AT2G26670.1; AT2G26670. [O48782-1] DR Gramene; AT2G26670.2; AT2G26670.2; AT2G26670. [O48782-2] DR KEGG; ath:AT2G26670; -. DR Araport; AT2G26670; -. DR TAIR; AT2G26670; TED4. DR eggNOG; KOG4480; Eukaryota. DR HOGENOM; CLU_063325_1_1_1; -. DR InParanoid; O48782; -. DR OMA; PPEFICH; -. DR OrthoDB; 1366343at2759; -. DR PhylomeDB; O48782; -. DR BioCyc; ARA:AT2G26670-MONOMER; -. DR BioCyc; MetaCyc:AT2G26670-MONOMER; -. DR PRO; PR:O48782; -. DR Proteomes; UP000006548; Chromosome 2. DR ExpressionAtlas; O48782; baseline and differential. DR GO; GO:0009507; C:chloroplast; IDA:TAIR. DR GO; GO:0020037; F:heme binding; IDA:TAIR. DR GO; GO:0004392; F:heme oxygenase (decyclizing) activity; IDA:TAIR. DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW. DR GO; GO:0016117; P:carotenoid biosynthetic process; IMP:TAIR. DR GO; GO:0071494; P:cellular response to UV-C; IMP:TAIR. DR GO; GO:0010019; P:chloroplast-nucleus signaling pathway; IMP:TAIR. DR GO; GO:0009813; P:flavonoid biosynthetic process; IMP:TAIR. DR GO; GO:0006788; P:heme oxidation; IEA:InterPro. DR GO; GO:0015979; P:photosynthesis; IEA:UniProtKB-KW. DR GO; GO:0010024; P:phytochromobilin biosynthetic process; IDA:TAIR. DR GO; GO:0010075; P:regulation of meristem growth; IGI:TAIR. DR GO; GO:0010119; P:regulation of stomatal movement; IGI:TAIR. DR CDD; cd19165; HemeO; 1. DR Gene3D; 1.20.910.10; Heme oxygenase-like; 1. DR InterPro; IPR002051; Haem_Oase. DR InterPro; IPR016053; Haem_Oase-like. DR InterPro; IPR016084; Haem_Oase-like_multi-hlx. DR InterPro; IPR016951; Haem_Oase_decyc_pln. DR PANTHER; PTHR35703; HEME OXYGENASE 1, CHLOROPLASTIC-RELATED; 1. DR PANTHER; PTHR35703:SF2; HEME OXYGENASE 1, CHLOROPLASTIC-RELATED; 1. DR Pfam; PF01126; Heme_oxygenase; 1. DR PIRSF; PIRSF030219; Heme_Oase_decyc_pln; 1. DR SUPFAM; SSF48613; Heme oxygenase-like; 1. DR Genevisible; O48782; AT. PE 1: Evidence at protein level; KW 3D-structure; Alternative splicing; Chloroplast; Heme; Iron; Metal-binding; KW Oxidoreductase; Photosynthesis; Plastid; Reference proteome; KW Transit peptide. FT TRANSIT 1..54 FT /note="Chloroplast" FT /evidence="ECO:0000255" FT CHAIN 55..282 FT /note="Heme oxygenase 1, chloroplastic" FT /id="PRO_0000412185" FT BINDING 86 FT /ligand="heme b" FT /ligand_id="ChEBI:CHEBI:60344" FT /ligand_part="Fe" FT /ligand_part_id="ChEBI:CHEBI:18248" FT /note="axial binding residue" FT /evidence="ECO:0000250" FT VAR_SEQ 94..142 FT /note="GEKETKSIEERPVAKWEPTVEGYLRFLVDSKLVYDTLELIIQDSNFPTY -> FT D (in isoform 2)" FT /evidence="ECO:0000305" FT /id="VSP_041652" FT HELIX 74..84 FT /evidence="ECO:0007829|PDB:7EQH" FT TURN 88..90 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 101..103 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 106..108 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 113..135 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 140..143 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 153..165 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 175..190 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 192..206 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 209..221 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 228..230 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 236..251 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 256..264 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 266..277 FT /evidence="ECO:0007829|PDB:7EQH" FT HELIX 278..281 FT /evidence="ECO:0007829|PDB:7EQH" SQ SEQUENCE 282 AA; 32691 MW; 65D9638890A3E8BA CRC64; MAYLAPISSS LSIFKNPQLS RFQFSSSSPN PLFLRPRIQI LSMTMNKSPS LVVVAATTAA EKQKKRYPGE SKGFVEEMRF VAMRLHTKDQ AKEGEKETKS IEERPVAKWE PTVEGYLRFL VDSKLVYDTL ELIIQDSNFP TYAEFKNTGL ERAEKLSTDL EWFKEQGYEI PEPTAPGKTY SQYLKELAEK DPQAFICHFY NIYFAHSAGG RMIGRKVAER ILDNKELEFY KWDGELSQLL QNVREKLNKV AEEWTREEKN HCLEETEKSF KYSGEILRLI LS //