ID KASC2_ARATH Reviewed; 541 AA. AC Q9C9P4; Q8RXF5; Q945N5; Q9SSG8; DT 08-MAR-2011, integrated into UniProtKB/Swiss-Prot. DT 01-JUN-2001, sequence version 1. DT 27-MAR-2024, entry version 143. DE RecName: Full=3-oxoacyl-[acyl-carrier-protein] synthase II, chloroplastic; DE EC=2.3.1.41; DE AltName: Full=Beta-ketoacyl-acyl-carrier-protein synthase II; DE Short=AtKAS2; DE Short=Beta-ketoacyl-ACP synthetase 2; DE AltName: Full=Protein FATTY ACID BIOSYNTHESIS 1; DE Flags: Precursor; GN Name=KAS2; Synonyms=FAB1; OrderedLocusNames=At1g74960; GN ORFNames=F25A4.7, F9E10.19; 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], FUNCTION, AND MUTAGENESIS OF LEU-337. RC STRAIN=cv. Wassilewskija; RX PubMed=12148534; DOI=10.1046/j.1365-313x.2002.01253.x; RA Carlsson A.S., LaBrie S.T., Kinney A.J., von Wettstein-Knowles P., RA Browse J.; RT "A KAS2 cDNA complements the phenotypes of the Arabidopsis fab1 mutant that RT differs in a single residue bordering the substrate binding pocket."; RL Plant J. 29:761-770(2002). RN [2] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=cv. Columbia; RX PubMed=11130712; DOI=10.1038/35048500; RA Theologis A., Ecker J.R., Palm C.J., Federspiel N.A., Kaul S., White O., RA Alonso J., Altafi H., Araujo R., Bowman C.L., Brooks S.Y., Buehler E., RA Chan A., Chao Q., Chen H., Cheuk R.F., Chin C.W., Chung M.K., Conn L., RA Conway A.B., Conway A.R., Creasy T.H., Dewar K., Dunn P., Etgu P., RA Feldblyum T.V., Feng J.-D., Fong B., Fujii C.Y., Gill J.E., Goldsmith A.D., RA Haas B., Hansen N.F., Hughes B., Huizar L., Hunter J.L., Jenkins J., RA Johnson-Hopson C., Khan S., Khaykin E., Kim C.J., Koo H.L., RA Kremenetskaia I., Kurtz D.B., Kwan A., Lam B., Langin-Hooper S., Lee A., RA Lee J.M., Lenz C.A., Li J.H., Li Y.-P., Lin X., Liu S.X., Liu Z.A., RA Luros J.S., Maiti R., Marziali A., Militscher J., Miranda M., Nguyen M., RA Nierman W.C., Osborne B.I., Pai G., Peterson J., Pham P.K., Rizzo M., RA Rooney T., Rowley D., Sakano H., Salzberg S.L., Schwartz J.R., Shinn P., RA Southwick A.M., Sun H., Tallon L.J., Tambunga G., Toriumi M.J., Town C.D., RA Utterback T., Van Aken S., Vaysberg M., Vysotskaia V.S., Walker M., Wu D., RA Yu G., Fraser C.M., Venter J.C., Davis R.W.; RT "Sequence and analysis of chromosome 1 of the plant Arabidopsis thaliana."; RL Nature 408:816-820(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=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 [5] RP FUNCTION, CATALYTIC ACTIVITY, AND MUTAGENESIS OF LEU-337. RC STRAIN=cv. Columbia; RX PubMed=12232312; DOI=10.1104/pp.106.1.143; RA Wu J., James D.W. Jr., Dooner H.K., Browse J.; RT "A Mutant of Arabidopsis Deficient in the Elongation of Palmitic Acid."; RL Plant Physiol. 106:143-150(1994). RN [6] RP FUNCTION, AND MUTAGENESIS OF LEU-337. RC STRAIN=cv. Columbia; RX PubMed=12242349; DOI=10.1105/tpc.7.1.17; RA Wu J., Browse J.; RT "Elevated levels of high-melting-point phosphatidylglycerols do not induce RT chilling sensitivity in an Arabidopsis mutant."; RL Plant Cell 7:17-27(1995). RN [7] RP FUNCTION, AND MUTAGENESIS OF LEU-337. RC STRAIN=cv. Columbia; RX PubMed=9046588; DOI=10.1104/pp.113.2.347; RA Wu J., Lightner J., Warwick N., Browse J.; RT "Low-temperature damage and subsequent recovery of fab1 mutant Arabidopsis RT exposed to 2 degrees C."; RL Plant Physiol. 113:347-356(1997). RN [8] RP FUNCTION, DISRUPTION PHENOTYPE, AND MUTAGENESIS OF LEU-337. RX PubMed=17360594; DOI=10.1073/pnas.0611141104; RA Pidkowich M.S., Nguyen H.T., Heilmann I., Ischebeck T., Shanklin J.; RT "Modulating seed beta-ketoacyl-acyl carrier protein synthase II level RT converts the composition of a temperate seed oil to that of a palm-like RT tropical oil."; RL Proc. Natl. Acad. Sci. U.S.A. 104:4742-4747(2007). RN [9] RP FUNCTION, DISRUPTION PHENOTYPE, TISSUE SPECIFICITY, AND DEVELOPMENTAL RP STAGE. RC STRAIN=cv. Columbia; RX PubMed=18506098; DOI=10.1266/ggs.83.143; RA Hakozaki H., Park J.-I., Endo M., Takada Y., Kazama T., Takeda Y., RA Suzuki G., Kawagishi-Kobayashi M., Watanabe M.; RT "Expression and developmental function of the 3-ketoacyl-ACP synthase2 gene RT in Arabidopsis thaliana."; RL Genes Genet. Syst. 83:143-152(2008). RN [10] RP IDENTIFICATION BY MASS SPECTROMETRY, AND SUBCELLULAR LOCATION [LARGE SCALE RP ANALYSIS]. RX PubMed=18431481; DOI=10.1371/journal.pone.0001994; RA Zybailov B., Rutschow H., Friso G., Rudella A., Emanuelsson O., Sun Q., RA van Wijk K.J.; RT "Sorting signals, N-terminal modifications and abundance of the chloroplast RT proteome."; RL PLoS ONE 3:E1994-E1994(2008). CC -!- FUNCTION: Essential protein that catalyzes the condensation reaction of CC fatty acid synthesis by the addition to an acyl acceptor of two carbons CC from malonyl-ACP. Specific for elongation from C-16 and C-16 to CC unsaturated C-18 fatty acids. Confers resistance to low temperatures by CC maintaining chloroplast membranes integrity. Involved in the regulation CC of fatty acids ratios during seed metabolism. Required for embryo CC development, especially at the transition from the globular to the CC heart stage. {ECO:0000269|PubMed:12148534, ECO:0000269|PubMed:12232312, CC ECO:0000269|PubMed:12242349, ECO:0000269|PubMed:17360594, CC ECO:0000269|PubMed:18506098, ECO:0000269|PubMed:9046588}. CC -!- CATALYTIC ACTIVITY: CC Reaction=a fatty acyl-[ACP] + H(+) + malonyl-[ACP] = a 3-oxoacyl-[ACP] CC + CO2 + holo-[ACP]; Xref=Rhea:RHEA:22836, Rhea:RHEA-COMP:9623, CC Rhea:RHEA-COMP:9685, Rhea:RHEA-COMP:9916, Rhea:RHEA-COMP:14125, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, ChEBI:CHEBI:64479, CC ChEBI:CHEBI:78449, ChEBI:CHEBI:78776, ChEBI:CHEBI:138651; CC EC=2.3.1.41; Evidence={ECO:0000269|PubMed:12232312}; CC -!- SUBUNIT: Homodimer. {ECO:0000250}. CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast stroma CC {ECO:0000269|PubMed:18431481}. CC -!- TISSUE SPECIFICITY: Mostly expressed in siliques, and, to a lower CC extent, in leaves, stems, flower buds, and flowers. CC {ECO:0000269|PubMed:18506098}. CC -!- DEVELOPMENTAL STAGE: First observed during the transition from the late CC globular to the early heart embryo stages. Later observed during heart, CC tropedo, and cotyledonary embryo stages. In seedlings, observed in the CC shoot apex and stomatal guard cells. In adult plants, expressed in CC inflorescences. In flowers, strongly present in styles and pollen CC grains. {ECO:0000269|PubMed:18506098}. CC -!- DISRUPTION PHENOTYPE: Lethal when homozygous due to embryo abortion CC before the torpedo stage. Converts temperate oilseed composition (rich CC in unsaturated 18-carbon fatty acids) to that of a palm-like tropical CC oil (enriched in saturated 16-carbon fatty acids). CC {ECO:0000269|PubMed:17360594, ECO:0000269|PubMed:18506098}. CC -!- SIMILARITY: Belongs to the thiolase-like superfamily. Beta-ketoacyl-ACP CC synthases family. {ECO:0000305}. CC -!- SEQUENCE CAUTION: CC Sequence=AAD55280.1; Type=Erroneous gene model prediction; Evidence={ECO:0000305}; CC Sequence=AAL06498.1; Type=Erroneous initiation; Note=Truncated N-terminus.; Evidence={ECO:0000305}; CC Sequence=AAL06498.1; Type=Frameshift; 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; AF318307; AAK69603.1; -; mRNA. DR EMBL; AC008263; AAD55280.1; ALT_SEQ; Genomic_DNA. DR EMBL; AC013258; AAG51920.1; -; Genomic_DNA. DR EMBL; CP002684; AEE35655.1; -; Genomic_DNA. DR EMBL; CP002684; AEE35656.1; -; Genomic_DNA. DR EMBL; CP002684; AEE35657.1; -; Genomic_DNA. DR EMBL; AF412045; AAL06498.1; ALT_FRAME; mRNA. DR EMBL; AF419598; AAL31930.1; -; mRNA. DR EMBL; AY054196; AAL06857.1; -; mRNA. DR EMBL; AY081285; AAL91174.1; -; mRNA. DR EMBL; AY097344; AAM19860.1; -; mRNA. DR PIR; D96779; D96779. DR RefSeq; NP_001185400.1; NM_001198471.1. DR RefSeq; NP_565097.1; NM_106154.4. DR RefSeq; NP_849888.1; NM_179557.4. DR AlphaFoldDB; Q9C9P4; -. DR SMR; Q9C9P4; -. DR BioGRID; 29054; 1. DR STRING; 3702.Q9C9P4; -. DR PaxDb; 3702-AT1G74960-2; -. DR ProteomicsDB; 250617; -. DR EnsemblPlants; AT1G74960.1; AT1G74960.1; AT1G74960. DR EnsemblPlants; AT1G74960.2; AT1G74960.2; AT1G74960. DR EnsemblPlants; AT1G74960.3; AT1G74960.3; AT1G74960. DR GeneID; 843835; -. DR Gramene; AT1G74960.1; AT1G74960.1; AT1G74960. DR Gramene; AT1G74960.2; AT1G74960.2; AT1G74960. DR Gramene; AT1G74960.3; AT1G74960.3; AT1G74960. DR KEGG; ath:AT1G74960; -. DR Araport; AT1G74960; -. DR TAIR; AT1G74960; FAB1. DR eggNOG; KOG1394; Eukaryota. DR HOGENOM; CLU_000022_69_1_1; -. DR InParanoid; Q9C9P4; -. DR OMA; LNAWRIT; -. DR OrthoDB; 5396558at2759; -. DR PhylomeDB; Q9C9P4; -. DR BioCyc; ARA:MONOMER-14118; -. DR BioCyc; MetaCyc:MONOMER-14118; -. DR BRENDA; 2.3.1.179; 399. DR PRO; PR:Q9C9P4; -. DR Proteomes; UP000006548; Chromosome 1. DR ExpressionAtlas; Q9C9P4; baseline and differential. DR GO; GO:0009507; C:chloroplast; HDA:TAIR. DR GO; GO:0009570; C:chloroplast stroma; HDA:TAIR. DR GO; GO:0005829; C:cytosol; HDA:TAIR. DR GO; GO:0009536; C:plastid; ISS:TAIR. DR GO; GO:0004315; F:3-oxoacyl-[acyl-carrier-protein] synthase activity; IDA:TAIR. DR GO; GO:0009631; P:cold acclimation; IMP:UniProtKB. DR GO; GO:0009793; P:embryo development ending in seed dormancy; IMP:UniProtKB. DR GO; GO:0006633; P:fatty acid biosynthetic process; IDA:TAIR. DR GO; GO:0006636; P:unsaturated fatty acid biosynthetic process; TAS:TAIR. DR CDD; cd00834; KAS_I_II; 1. DR Gene3D; 3.40.47.10; -; 1. DR InterPro; IPR017568; 3-oxoacyl-ACP_synth-2. DR InterPro; IPR000794; Beta-ketoacyl_synthase. DR InterPro; IPR018201; Ketoacyl_synth_AS. DR InterPro; IPR014031; Ketoacyl_synth_C. DR InterPro; IPR014030; Ketoacyl_synth_N. DR InterPro; IPR020841; PKS_Beta-ketoAc_synthase_dom. DR InterPro; IPR016039; Thiolase-like. DR NCBIfam; TIGR03150; fabF; 1. DR PANTHER; PTHR11712:SF332; 3-OXOACYL-[ACYL-CARRIER-PROTEIN] SYNTHASE II, CHLOROPLASTIC; 1. DR PANTHER; PTHR11712; POLYKETIDE SYNTHASE-RELATED; 1. DR Pfam; PF00109; ketoacyl-synt; 1. DR Pfam; PF02801; Ketoacyl-synt_C; 1. DR SMART; SM00825; PKS_KS; 1. DR SUPFAM; SSF53901; Thiolase-like; 2. DR PROSITE; PS00606; KS3_1; 1. DR PROSITE; PS52004; KS3_2; 1. DR Genevisible; Q9C9P4; AT. PE 1: Evidence at protein level; KW Acyltransferase; Chloroplast; Developmental protein; KW Fatty acid biosynthesis; Fatty acid metabolism; Lipid biosynthesis; KW Lipid metabolism; Plastid; Reference proteome; Transferase; KW Transit peptide. FT TRANSIT 1..103 FT /note="Chloroplast" FT /evidence="ECO:0000255" FT CHAIN 104..541 FT /note="3-oxoacyl-[acyl-carrier-protein] synthase II, FT chloroplastic" FT /id="PRO_0000406094" FT DOMAIN 129..539 FT /note="Ketosynthase family 3 (KS3)" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT ACT_SITE 292 FT /note="For beta-ketoacyl synthase activity" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT ACT_SITE 432 FT /note="For beta-ketoacyl synthase activity" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT ACT_SITE 468 FT /note="For beta-ketoacyl synthase activity" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT MUTAGEN 337 FT /note="L->F: In fab1; partial activity deficiency due to FT structural instability and reduced substrate binding FT affinity, resulting in increased levels of saturated 16:0 FT but reduced levels of 18:0 fatty acids, particularly in FT chloroplasts, and associated with damage and death at FT continuous low temperature (accompanied by chloroplast FT degenerescence), but not after transient chilling or FT freezing." FT /evidence="ECO:0000269|PubMed:12148534, FT ECO:0000269|PubMed:12232312, ECO:0000269|PubMed:12242349, FT ECO:0000269|PubMed:17360594, ECO:0000269|PubMed:9046588" FT CONFLICT 472 FT /note="A -> V (in Ref. 4; AAL91174)" FT /evidence="ECO:0000305" SQ SEQUENCE 541 AA; 57600 MW; CB4F87E7B0C82189 CRC64; MVGASSSYAS PLCTWFVAAC MSVSHGGGDS RQAVALQSGG RSRRRRQLSK CSVASGSASI QALVTSCLDF GPCTHYNNNN ALSSLFGSNS VSLNRNQRRL NRAASSGGAM AVMEMEKEAA VNKKPPTEQR RVVVTGMGVE TSLGHDPHTF YENLLQGNSG ISQIENFDCS EFPTRIAGEI KSFSTEGWVA PKLSKRMDKF MLYLLTAGKK ALADGGVTDE VMAEFDKTKC GVLIGSAMGG MKVFYDAIEA LRISYKKMNP FCVPFATTNM GSAMLAMDLG WMGPNYSIST ACATSNFCIL NSANHIIKGE ADVMLCGGSD AVIIPIGLGG FVACRALSQR NNDPTKASRP WDTNRDGFVM GEGAGVLLLE ELEHAKKRGA TIYAEFLGGS FTCDAYHMTE PHPDGAGVIL CIERALASAG ISKEQINYIN AHATSTHAGD IKEYQALAHC FGQNPELKVN STKSMIGHLL GAAGAVEAVA TVQAIRTGWV HPNINLENPD SGVDTKLLVG PKKERLDIKA ALSNSFGFGG HNSSIIFAPY K //