CY561_SHEEP
ID CY561_SHEEP Reviewed; 252 AA.
AC Q95204;
DT 01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT 01-FEB-1997, sequence version 1.
DT 03-AUG-2022, entry version 104.
DE RecName: Full=Transmembrane ascorbate-dependent reductase CYB561 {ECO:0000305};
DE EC=7.2.1.- {ECO:0000250|UniProtKB:P10897};
DE AltName: Full=Cytochrome b-561;
DE AltName: Full=Cytochrome b561;
GN Name=CYB561;
OS Ovis aries (Sheep).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Laurasiatheria; Artiodactyla; Ruminantia; Pecora; Bovidae;
OC Caprinae; Ovis.
OX NCBI_TaxID=9940;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Adrenal medulla;
RX PubMed=9602148; DOI=10.1016/s0167-4838(97)00216-1;
RA Okuyama E., Yamamoto R., Ichikawa Y., Tsubaki M.;
RT "Structural basis for the electron transfer across the chromaffin vesicle
RT membranes catalyzed by cytochrome b561: analyses of cDNA nucleotide
RT sequences and visible absorption spectra.";
RL Biochim. Biophys. Acta 1383:269-278(1998).
CC -!- FUNCTION: Transmembrane reductase that uses ascorbate as an electron
CC donor in the cytoplasm and transfers electrons across membranes to
CC reduce monodehydro-L-ascorbate radical in the lumen of secretory
CC vesicles. It is therefore involved the regeneration and homeostasis
CC within secretory vesicles of ascorbate which in turn provides reducing
CC equivalents needed to support the activity of intravesicular enzymes.
CC {ECO:0000250|UniProtKB:P10897}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=L-ascorbate(in) + monodehydro-L-ascorbate radical(out) = L-
CC ascorbate(out) + monodehydro-L-ascorbate radical(in);
CC Xref=Rhea:RHEA:66524, ChEBI:CHEBI:38290, ChEBI:CHEBI:59513;
CC Evidence={ECO:0000250|UniProtKB:P10897};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:66525;
CC Evidence={ECO:0000250|UniProtKB:P10897};
CC -!- COFACTOR:
CC Name=heme b; Xref=ChEBI:CHEBI:60344;
CC Evidence={ECO:0000250|UniProtKB:P10897};
CC Note=Binds 2 heme b groups non-covalently.
CC {ECO:0000250|UniProtKB:P10897};
CC -!- SUBCELLULAR LOCATION: Cytoplasmic vesicle, secretory vesicle,
CC chromaffin granule membrane {ECO:0000250|UniProtKB:P10897}; Multi-pass
CC membrane protein {ECO:0000250|UniProtKB:Q53TN4}. Note=Secretory vesicle
CC containing catecholamines and amidated peptides.
CC {ECO:0000250|UniProtKB:P10897}.
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DR EMBL; D88157; BAA13548.1; -; mRNA.
DR RefSeq; NP_001087259.1; NM_001093790.1.
DR AlphaFoldDB; Q95204; -.
DR SMR; Q95204; -.
DR STRING; 9940.ENSOARP00000013809; -.
DR GeneID; 100048995; -.
DR KEGG; oas:100048995; -.
DR CTD; 1534; -.
DR eggNOG; KOG1619; Eukaryota.
DR OrthoDB; 1503869at2759; -.
DR Proteomes; UP000002356; Unplaced.
DR GO; GO:0042584; C:chromaffin granule membrane; ISS:UniProtKB.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0140575; F:transmembrane monodehydroascorbate reductase activity; ISS:UniProtKB.
DR GO; GO:0140576; P:ascorbate homeostasis; ISS:UniProtKB.
DR InterPro; IPR028837; CYB561.
DR InterPro; IPR043205; CYB561/CYBRD1-like.
DR InterPro; IPR006593; Cyt_b561/ferric_Rdtase_TM.
DR PANTHER; PTHR10106; PTHR10106; 1.
DR PANTHER; PTHR10106:SF14; PTHR10106:SF14; 1.
DR Pfam; PF03188; Cytochrom_B561; 1.
DR SMART; SM00665; B561; 1.
DR PROSITE; PS50939; CYTOCHROME_B561; 1.
PE 2: Evidence at transcript level;
KW Acetylation; Cytoplasmic vesicle; Electron transport; Heme; Iron; Membrane;
KW Metal-binding; Phosphoprotein; Reference proteome; Translocase;
KW Transmembrane; Transmembrane helix; Transport.
FT CHAIN 1..252
FT /note="Transmembrane ascorbate-dependent reductase CYB561"
FT /id="PRO_0000151031"
FT TOPO_DOM 1..17
FT /note="Cytoplasmic"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT TRANSMEM 18..38
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 39..52
FT /note="Vesicular"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT TRANSMEM 53..73
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 74..86
FT /note="Cytoplasmic"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT TRANSMEM 87..107
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 108..125
FT /note="Vesicular"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT TRANSMEM 126..146
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 147..159
FT /note="Cytoplasmic"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT TRANSMEM 160..180
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 181..199
FT /note="Vesicular"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT TRANSMEM 200..220
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 221..252
FT /note="Cytoplasmic"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT DOMAIN 20..221
FT /note="Cytochrome b561"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00242"
FT BINDING 54
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="1"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 74
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="2"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 81
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="2"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 81
FT /ligand="L-ascorbate"
FT /ligand_id="ChEBI:CHEBI:38290"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 85
FT /ligand="L-ascorbate"
FT /ligand_id="ChEBI:CHEBI:38290"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 88
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="2"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 117..120
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="1"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 122
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="1"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 154
FT /ligand="L-ascorbate"
FT /ligand_id="ChEBI:CHEBI:38290"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 161
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="2"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 182
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="1"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT BINDING 226
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="2"
FT /evidence="ECO:0000250|UniProtKB:Q53TN4"
FT MOD_RES 1
FT /note="N-acetylmethionine"
FT /evidence="ECO:0000250|UniProtKB:P10897"
FT MOD_RES 248
FT /note="Phosphoserine"
FT /evidence="ECO:0000250|UniProtKB:Q60720"
FT MOD_RES 250
FT /note="Phosphoserine"
FT /evidence="ECO:0000250|UniProtKB:Q60720"
SQ SEQUENCE 252 AA; 27745 MW; 2DF5FD2C3F0D0C97 CRC64;
MEGPASPAPA PGALPYYVAF SQLLGLTVVA MTGAWLGMYR GGIAWESALQ FNVHPLCMVI
GLVFLQGDAL LVYRVFRNEA KRTTKVLHGL LHVFAFVIAL VGLVAVFEHH RKKGYADLYS
LHSWCGILVF ALFFAQWLVG FSFFLFPGAS FSLRSRYRPQ HVFFGAAIFL LSVATALLGL
KEALLFELGT KYSTFEPEGV LANVLGLLLA AFATVVLYIL TRADWKRPLQ AEEQALSMDF
KTLTEGDSPS SQ
