ID   RGN_XENTR               Reviewed;         299 AA.
AC   Q6DF62;
DT   15-MAY-2007, integrated into UniProtKB/Swiss-Prot.
DT   16-AUG-2004, sequence version 1.
DT   03-AUG-2022, entry version 97.
DE   RecName: Full=Regucalcin;
DE            Short=RC;
DE   AltName: Full=Gluconolactonase;
DE            Short=GNL;
DE            EC=3.1.1.17;
GN   Name=rgn {ECO:0000312|EMBL:AAH76881.1};
OS   Xenopus tropicalis (Western clawed frog) (Silurana tropicalis).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC   Batrachia; Anura; Pipoidea; Pipidae; Xenopodinae; Xenopus; Silurana.
OX   NCBI_TaxID=8364;
RN   [1] {ECO:0000312|EMBL:AAH76881.1}
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RG   NIH - Xenopus Gene Collection (XGC) project;
RL   Submitted (JUL-2004) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Gluconolactonase with low activity towards other sugar
CC       lactones, including gulonolactone and galactonolactone. Catalyzes a key
CC       step in ascorbic acid (vitamin C) biosynthesis. Can also hydrolyze
CC       diisopropyl phosphorofluoridate and phenylacetate (in vitro). Calcium-
CC       binding protein. Modulates Ca(2+) signaling, and Ca(2+)-dependent
CC       cellular processes and enzyme activities (By similarity).
CC       {ECO:0000250}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=D-glucono-1,5-lactone + H2O = D-gluconate + H(+);
CC         Xref=Rhea:RHEA:10440, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:16217, ChEBI:CHEBI:18391; EC=3.1.1.17;
CC   -!- COFACTOR:
CC       Name=Zn(2+); Xref=ChEBI:CHEBI:29105; Evidence={ECO:0000250};
CC       Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000250};
CC       Name=Ca(2+); Xref=ChEBI:CHEBI:29108; Evidence={ECO:0000250};
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250};
CC       Note=Binds 1 divalent metal cation per subunit. Most active with Zn(2+)
CC       and Mn(2+) ions. The physiological cofactor is most likely Ca(2+) or
CC       Mg(2+). {ECO:0000250};
CC   -!- PATHWAY: Cofactor biosynthesis; L-ascorbate biosynthesis via UDP-alpha-
CC       D-glucuronate pathway; L-ascorbate from UDP-alpha-D-glucuronate: step
CC       3/4.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000250|UniProtKB:Q03336}.
CC   -!- SIMILARITY: Belongs to the SMP-30/CGR1 family.
CC       {ECO:0000250|UniProtKB:Q03336}.
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DR   EMBL; BC076881; AAH76881.1; -; mRNA.
DR   RefSeq; NP_001006822.1; NM_001006821.1.
DR   RefSeq; XP_012812212.1; XM_012956758.2.
DR   AlphaFoldDB; Q6DF62; -.
DR   SMR; Q6DF62; -.
DR   STRING; 8364.ENSXETP00000008925; -.
DR   PaxDb; Q6DF62; -.
DR   PRIDE; Q6DF62; -.
DR   DNASU; 448549; -.
DR   GeneID; 448549; -.
DR   KEGG; xtr:448549; -.
DR   CTD; 9104; -.
DR   Xenbase; XB-GENE-483637; rgn.
DR   eggNOG; KOG4499; Eukaryota.
DR   HOGENOM; CLU_036110_3_2_1; -.
DR   InParanoid; Q6DF62; -.
DR   OMA; HLWICHY; -.
DR   OrthoDB; 1343872at2759; -.
DR   PhylomeDB; Q6DF62; -.
DR   TreeFam; TF323663; -.
DR   UniPathway; UPA00991; UER00938.
DR   Proteomes; UP000008143; Chromosome 2.
DR   Proteomes; UP000790000; Unplaced.
DR   Bgee; ENSXETG00000004129; Expressed in mesonephros and 15 other tissues.
DR   GO; GO:0005737; C:cytoplasm; ISS:UniProtKB.
DR   GO; GO:0005634; C:nucleus; ISS:UniProtKB.
DR   GO; GO:0005509; F:calcium ion binding; ISS:UniProtKB.
DR   GO; GO:0030234; F:enzyme regulator activity; IEA:InterPro.
DR   GO; GO:0004341; F:gluconolactonase activity; ISS:UniProtKB.
DR   GO; GO:0008270; F:zinc ion binding; ISS:UniProtKB.
DR   GO; GO:0006874; P:cellular calcium ion homeostasis; ISS:UniProtKB.
DR   GO; GO:0019853; P:L-ascorbic acid biosynthetic process; ISS:UniProtKB.
DR   GO; GO:0032781; P:positive regulation of ATP-dependent activity; ISS:UniProtKB.
DR   GO; GO:0050848; P:regulation of calcium-mediated signaling; ISS:UniProtKB.
DR   Gene3D; 2.120.10.30; -; 1.
DR   InterPro; IPR011042; 6-blade_b-propeller_TolB-like.
DR   InterPro; IPR008367; Regucalcin.
DR   InterPro; IPR013658; SGL.
DR   InterPro; IPR005511; SMP-30.
DR   Pfam; PF08450; SGL; 1.
DR   PRINTS; PR01791; REGUCALCIN.
DR   PRINTS; PR01790; SMP30FAMILY.
PE   2: Evidence at transcript level;
KW   Ascorbate biosynthesis; Calcium; Cytoplasm; Hydrolase; Metal-binding;
KW   Reference proteome.
FT   CHAIN           1..299
FT                   /note="Regucalcin"
FT                   /id="PRO_0000287687"
FT   ACT_SITE        204
FT                   /note="Proton donor/acceptor"
FT                   /evidence="ECO:0000250"
FT   BINDING         18
FT                   /ligand="a divalent metal cation"
FT                   /ligand_id="ChEBI:CHEBI:60240"
FT                   /evidence="ECO:0000250"
FT   BINDING         101
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         103
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         121
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         154
FT                   /ligand="a divalent metal cation"
FT                   /ligand_id="ChEBI:CHEBI:60240"
FT                   /evidence="ECO:0000250"
FT   BINDING         204
FT                   /ligand="a divalent metal cation"
FT                   /ligand_id="ChEBI:CHEBI:60240"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   299 AA;  33079 MW;  342707A744622104 CRC64;
     MSSIKIECVV SETYKIGESP VWEEKDGTLL FVDITGQKVC RWDPGTKKVQ SVSLEAPVGS
     VVLRKSGGYV MAMGNTFSAL NWQDQSVTTL TCVDEDKPNN RFNDGKVDPE GRFLAGTMSQ
     EIRPAVVERN QGSLFTLYPD HSVVKHFDMV DISNGLDWSL DHKTLYYIDS LSFKVDALDY
     DMKTGKSSNR RTLYKLQQDE GIPDGMCIDA EGKLWVACYN GGRVIRIDPE TGKQIQTVKL
     PVDKTTSCCF GGPDYSEMYV TSACEGMDEE WKKRQPQSGG IYKITGLGVK GIAPTAFAG