ID   GLGS_ARATH              Reviewed;         520 AA.
AC   P55228; O64400; Q96534;
DT   01-OCT-1996, integrated into UniProtKB/Swiss-Prot.
DT   01-DEC-2000, sequence version 2.
DT   02-SEP-2026, entry version 173.
DE   RecName: Full=Glucose-1-phosphate adenylyltransferase small subunit, chloroplastic;
DE            EC=2.7.7.27;
DE   AltName: Full=ADP-glucose pyrophosphorylase;
DE   AltName: Full=ADP-glucose synthase;
DE   AltName: Full=AGPase B;
DE   AltName: Full=Alpha-D-glucose-1-phosphate adenyl transferase;
DE   Flags: Precursor;
GN   Name=APS1; Synonyms=ADG1, APS; OrderedLocusNames=At5g48300;
GN   ORFNames=K23F3.2;
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].
RC   STRAIN=cv. Columbia; TISSUE=Leaf;
RX   PubMed=9680965; DOI=10.1046/j.1365-313x.1998.00009.x;
RA   Wang S.-M., Lue W.-L., Yu T.-S., Long J.-H., Wang C.-N., Eimert K.,
RA   Chen J.;
RT   "Characterization of ADG1, an Arabidopsis locus encoding for ADPG
RT   pyrophosphorylase small subunit, demonstrates that the presence of the
RT   small subunit is required for large subunit stability.";
RL   Plant J. 13:63-70(1998).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   STRAIN=cv. Columbia;
RA   Choi S.B., Okita T.W.;
RT   "cDNA cloning of ADP glucose pyrophosphorylase small subunit in Arabidopsis
RT   thaliana.";
RL   Submitted (SEP-1996) to the EMBL/GenBank/DDBJ databases.
RN   [3]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC   STRAIN=cv. Columbia;
RA   Ito H., Kato C., Matsui H., Okita T.W.;
RT   "Isolation of ADPglucose pyrophosphorylase small subunit gene from
RT   Arabidopsis thaliana.";
RL   Submitted (MAR-2000) to the EMBL/GenBank/DDBJ databases.
RN   [4]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=cv. Columbia;
RA   Kaneko T., Katoh T., Asamizu E., Sato S., Nakamura Y., Kotani H.,
RA   Tabata S.;
RT   "Structural analysis of Arabidopsis thaliana chromosome 5. XI.";
RL   Submitted (JUL-1999) to the EMBL/GenBank/DDBJ databases.
RN   [5]
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   [6]
RP   GENOME REANNOTATION.
RC   STRAIN=cv. Columbia;
RG   The Arabidopsis Information Resource (TAIR);
RT   "Community-consensus reference genome of Arabidopsis thaliana Col-0.";
RL   Submitted (FEB-2026) to the EMBL/GenBank/DDBJ databases.
RN   [7]
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   [8]
RP   NUCLEOTIDE SEQUENCE [MRNA] OF 293-478.
RC   STRAIN=cv. Columbia;
RX   PubMed=8292792; DOI=10.1007/bf00042361;
RA   Villand P., Olsen O.-A., Kleczkowski L.A.;
RT   "Molecular characterization of multiple cDNA clones for ADP-glucose
RT   pyrophosphorylase from Arabidopsis thaliana.";
RL   Plant Mol. Biol. 23:1279-1284(1993).
CC   -!- FUNCTION: This protein plays a role in synthesis of starch. It
CC       catalyzes the synthesis of the activated glycosyl donor, ADP-glucose
CC       from Glc-1-P and ATP.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=alpha-D-glucose 1-phosphate + ATP + H(+) = ADP-alpha-D-glucose
CC         + diphosphate; Xref=Rhea:RHEA:12120, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:30616, ChEBI:CHEBI:33019, ChEBI:CHEBI:57498,
CC         ChEBI:CHEBI:58601; EC=2.7.7.27;
CC   -!- ACTIVITY REGULATION: Activated by 3'phosphoglycerate, inhibited by
CC       orthophosphate. Allosteric regulation.
CC   -!- PATHWAY: Glycan biosynthesis; starch biosynthesis.
CC   -!- SUBUNIT: Heterotetramer.
CC   -!- SUBCELLULAR LOCATION: Plastid, chloroplast {ECO:0000250}.
CC   -!- TISSUE SPECIFICITY: Leaves.
CC   -!- SIMILARITY: Belongs to the bacterial/plant glucose-1-phosphate
CC       adenylyltransferase family. {ECO:0000305}.
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DR   EMBL; U72351; AAC39441.1; -; mRNA.
DR   EMBL; U70616; AAB09585.1; -; mRNA.
DR   EMBL; AB039889; BAA92523.1; -; Genomic_DNA.
DR   EMBL; AP000372; BAA98187.1; -; Genomic_DNA.
DR   EMBL; CP002688; AED95648.1; -; Genomic_DNA.
DR   EMBL; OZ408687; CAO7055670.1; -; Genomic_DNA.
DR   EMBL; AY049265; AAK83607.1; -; mRNA.
DR   EMBL; AY065428; AAL38869.1; -; mRNA.
DR   EMBL; AY090283; AAL90944.1; -; mRNA.
DR   EMBL; AY096379; AAM20020.1; -; mRNA.
DR   EMBL; X73365; CAA51777.1; -; mRNA.
DR   RefSeq; NP_199641.1; NM_124205.4.
DR   AlphaFoldDB; P55228; -.
DR   EMDB; EMD-67269; -.
DR   EMDB; EMD-67270; -.
DR   EMDB; EMD-67271; -.
DR   EMDB; EMD-67274; -.
DR   EMDB; EMD-67276; -.
DR   SMR; P55228; -.
DR   BioGRID; 20129; 9.
DR   FunCoup; P55228; 1167.
DR   IntAct; P55228; 3.
DR   STRING; 3702.P55228; -.
DR   iPTMnet; P55228; -.
DR   PaxDb; 3702-P55228; -.
DR   ProteomicsDB; 220773; -.
DR   GeneID; 834883; -.
DR   KEGG; ath:AT5G48300; -.
DR   Araport; AT5G48300; -.
DR   TAIR; AT5G48300; ADG1.
DR   eggNOG; KOG1322; Eukaryota.
DR   HOGENOM; CLU_029499_14_4_1; -.
DR   InParanoid; P55228; -.
DR   OMA; AYHEASM; -.
DR   PhylomeDB; P55228; -.
DR   BioCyc; ARA:AT5G48300-MONOMER; -.
DR   BioCyc; MetaCyc:MONOMER-1822; -.
DR   BRENDA; 2.7.7.27; 399.
DR   SABIO-RK; P55228; -.
DR   UniPathway; UPA00152; -.
DR   CD-CODE; 4299E36E; Nucleolus.
DR   PRO; PR:P55228; -.
DR   Proteomes; UP000006548; Chromosome 5.
DR   ExpressionAtlas; P55228; baseline and differential.
DR   GO; GO:0048046; C:apoplast; HDA:TAIR.
DR   GO; GO:0009507; C:chloroplast; HDA:TAIR.
DR   GO; GO:0009570; C:chloroplast stroma; HDA:TAIR.
DR   GO; GO:0030931; C:heterotetrameric ADPG pyrophosphorylase complex; IMP:TAIR.
DR   GO; GO:0009536; C:plastid; HDA:TAIR.
DR   GO; GO:0008878; F:glucose-1-phosphate adenylyltransferase activity; IDA:TAIR.
DR   GO; GO:0005978; P:glycogen biosynthetic process; IEA:InterPro.
DR   GO; GO:0048573; P:photoperiodism, flowering; IMP:TAIR.
DR   GO; GO:0019252; P:starch biosynthetic process; IMP:TAIR.
DR   CDD; cd02508; ADP_Glucose_PP; 1.
DR   CDD; cd04651; LbH_G1P_AT_C; 1.
DR   FunFam; 2.160.10.10:FF:000010; Glucose-1-phosphate adenylyltransferase; 1.
DR   FunFam; 3.90.550.10:FF:000030; Glucose-1-phosphate adenylyltransferase; 1.
DR   Gene3D; 2.160.10.10; Hexapeptide repeat proteins; 1.
DR   Gene3D; 3.90.550.10; Spore Coat Polysaccharide Biosynthesis Protein SpsA, Chain A; 1.
DR   InterPro; IPR011831; ADP-Glc_PPase.
DR   InterPro; IPR005836; ADP_Glu_pyroP_CS.
DR   InterPro; IPR064045; LbH_GLGC.
DR   InterPro; IPR005835; NTP_transferase_dom.
DR   InterPro; IPR029044; Nucleotide-diphossugar_trans.
DR   InterPro; IPR011004; Trimer_LpxA-like_sf.
DR   NCBIfam; TIGR02091; glgC; 1.
DR   NCBIfam; NF002772; PRK02862.1; 1.
DR   PANTHER; PTHR43523:SF12; GLUCOSE-1-PHOSPHATE ADENYLYLTRANSFERASE LARGE SUBUNIT 1, CHLOROPLASTIC-RELATED; 1.
DR   PANTHER; PTHR43523; GLUCOSE-1-PHOSPHATE ADENYLYLTRANSFERASE-RELATED; 1.
DR   Pfam; PF25247; LbH_GLGC; 1.
DR   Pfam; PF00483; NTP_transferase; 1.
DR   SUPFAM; SSF53448; Nucleotide-diphospho-sugar transferases; 1.
DR   SUPFAM; SSF51161; Trimeric LpxA-like enzymes; 1.
DR   PROSITE; PS00808; ADP_GLC_PYROPHOSPH_1; 1.
DR   PROSITE; PS00809; ADP_GLC_PYROPHOSPH_2; 1.
DR   PROSITE; PS00810; ADP_GLC_PYROPHOSPH_3; 1.
PE   2: Evidence at transcript level;
KW   Allosteric enzyme; ATP-binding; Chloroplast; Nucleotide-binding;
KW   Nucleotidyltransferase; Plastid; Reference proteome; Starch biosynthesis;
KW   Transferase; Transit peptide.
FT   TRANSIT         1..71
FT                   /note="Chloroplast"
FT                   /evidence="ECO:0000255"
FT   CHAIN           72..520
FT                   /note="Glucose-1-phosphate adenylyltransferase small
FT                   subunit, chloroplastic"
FT                   /id="PRO_0000011149"
FT   CONFLICT        194..195
FT                   /note="RQ -> TD (in Ref. 2; AAB09585)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        265
FT                   /note="A -> S (in Ref. 2; AAB09585)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        293..298
FT                   /note="MPFIAS -> YPYIAG (in Ref. 8; CAA51777)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        332..333
FT                   /note="TS -> PF (in Ref. 8; CAA51777)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        451
FT                   /note="S -> A (in Ref. 2; AAB09585)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        473
FT                   /note="K -> I (in Ref. 8; CAA51777)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        475
FT                   /note="A -> S (in Ref. 2; AAB09585)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   520 AA;  56651 MW;  49E8F3141A3C5C0F CRC64;
     MASVSAIGVL KVPPASTSNS TGKATEAVPT RTLSFSSSVT SSDDKISLKS TVSRLCKSVV
     RRNPIIVSPK AVSDSQNSQT CLDPDASSSV LGIILGGGAG TRLYPLTKKR AKPAVPLGAN
     YRLIDIPVSN CLNSNISKIY VLTQFNSASL NRHLSRAYAS NMGGYKNEGF VEVLAAQQSP
     ENPNWFQGTA DAVRQYLWLF EEHNVLEYLI LAGDHLYRMD YEKFIQAHRE TDADITVAAL
     PMDEQRATAF GLMKIDEEGR IIEFAEKPKG EHLKAMKVDT TILGLDDQRA KEMPFIASMG
     IYVVSRDVML DLLRNQFPGA NDFGSEVIPG ATSLGLRVQA YLYDGYWEDI GTIEAFYNAN
     LGITKKPVPD FSFYDRSAPI YTQPRYLPPS KMLDADVTDS VIGEGCVIKN CKIHHSVVGL
     RSCISEGAII EDSLLMGADY YETATEKSLL SAKGSVPIGI GKNSHIKRAI IDKNARIGDN
     VKIINSDNVQ EAARETDGYF IKSGIVTVIK DALIPTGTVI
//