ID   APOC3_CANLF             Reviewed;         100 AA.
AC   P12279;
DT   01-OCT-1989, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-1989, sequence version 1.
DT   25-MAY-2022, entry version 104.
DE   RecName: Full=Apolipoprotein C-III;
DE            Short=Apo-CIII;
DE            Short=ApoC-III;
DE   AltName: Full=Apolipoprotein C3;
DE   Flags: Precursor;
GN   Name=APOC3;
OS   Canis lupus familiaris (Dog) (Canis familiaris).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Laurasiatheria; Carnivora; Caniformia; Canidae; Canis.
OX   NCBI_TaxID=9615;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], AND TISSUE SPECIFICITY.
RX   PubMed=2956259; DOI=10.1016/s0021-9258(18)61003-8;
RA   Datta S., Li W.-H., Ghosh I., Luo C.-C., Chan L.;
RT   "Structure and expression of dog apolipoprotein C-II and C-III mRNAs.
RT   Implications for the evolution and functional constraints of apolipoprotein
RT   structure.";
RL   J. Biol. Chem. 262:10588-10593(1987).
CC   -!- FUNCTION: Component of triglyceride-rich very low density lipoproteins
CC       (VLDL) and high density lipoproteins (HDL) in plasma. Plays a
CC       multifaceted role in triglyceride homeostasis. Intracellularly,
CC       promotes hepatic very low density lipoprotein 1 (VLDL1) assembly and
CC       secretion; extracellularly, attenuates hydrolysis and clearance of
CC       triglyceride-rich lipoproteins (TRLs). Impairs the lipolysis of TRLs by
CC       inhibiting lipoprotein lipase and the hepatic uptake of TRLs by remnant
CC       receptors. Formed of several curved helices connected via semiflexible
CC       hinges, so that it can wrap tightly around the curved micelle surface
CC       and easily adapt to the different diameters of its natural binding
CC       partners. {ECO:0000250|UniProtKB:P02656}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:P02656}.
CC   -!- TISSUE SPECIFICITY: Synthesized predominantly in liver and to a lesser
CC       degree in intestine. {ECO:0000269|PubMed:2956259}.
CC   -!- PTM: The most abundant glycoforms are characterized by an O-linked
CC       disaccharide galactose linked to N-acetylgalactosamine (Gal-GalNAc),
CC       further modified with up to 3 sialic acid residues. Less abundant
CC       glycoforms are characterized by more complex and fucosylated glycan
CC       moieties. O-glycosylated on Thr-94 with a core 1 or possibly core 8
CC       glycan. {ECO:0000250|UniProtKB:P02656}.
CC   -!- SIMILARITY: Belongs to the apolipoprotein C3 family. {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; M17178; AAA30830.1; -; mRNA.
DR   PIR; B28487; B28487.
DR   AlphaFoldDB; P12279; -.
DR   SMR; P12279; -.
DR   STRING; 9612.ENSCAFP00000019635; -.
DR   PaxDb; P12279; -.
DR   eggNOG; ENOG502SZ00; Eukaryota.
DR   InParanoid; P12279; -.
DR   Proteomes; UP000002254; Unplaced.
DR   GO; GO:0042627; C:chylomicron; IEA:UniProtKB-KW.
DR   GO; GO:0034361; C:very-low-density lipoprotein particle; IEA:UniProtKB-KW.
DR   GO; GO:0008289; F:lipid binding; IEA:InterPro.
DR   GO; GO:0016042; P:lipid catabolic process; IEA:UniProtKB-KW.
DR   GO; GO:0006869; P:lipid transport; IEA:UniProtKB-KW.
DR   GO; GO:0042157; P:lipoprotein metabolic process; IEA:InterPro.
DR   Gene3D; 6.10.90.10; -; 1.
DR   InterPro; IPR008403; Apo-CIII.
DR   InterPro; IPR038195; Apo_CIII_sf.
DR   PANTHER; PTHR14225; PTHR14225; 1.
DR   Pfam; PF05778; Apo-CIII; 1.
PE   2: Evidence at transcript level;
KW   Chylomicron; Glycoprotein; Lipid degradation; Lipid metabolism;
KW   Lipid transport; Oxidation; Reference proteome; Secreted; Sialic acid;
KW   Signal; Transport; VLDL.
FT   SIGNAL          1..20
FT                   /evidence="ECO:0000255"
FT   CHAIN           21..100
FT                   /note="Apolipoprotein C-III"
FT                   /id="PRO_0000002029"
FT   REGION          68..99
FT                   /note="Lipid-binding"
FT                   /evidence="ECO:0000250"
FT   SITE            41
FT                   /note="May interact with the LDL receptor"
FT                   /evidence="ECO:0000250|UniProtKB:P02656"
FT   MOD_RES         63
FT                   /note="Methionine sulfoxide"
FT                   /evidence="ECO:0000250|UniProtKB:P33622"
FT   CARBOHYD        94
FT                   /note="O-linked (GalNAc...) threonine"
FT                   /evidence="ECO:0000250|UniProtKB:P02656"
SQ   SEQUENCE   100 AA;  10906 MW;  3D24443AB3B42D7D CRC64;
     MQPRVLLVAA LLALLASARA LEEEDPSLLG LMQGYMQHAT KTAQDTLTSV QESQVAQRAR
     GWMTDSFSSL KDYCSTFKGK FTGFWDSASE AKPTPASDAF