SPTC1_CRIGR
ID SPTC1_CRIGR Reviewed; 473 AA.
AC O54695;
DT 30-MAY-2000, integrated into UniProtKB/Swiss-Prot.
DT 01-JUN-1998, sequence version 1.
DT 25-MAY-2022, entry version 119.
DE RecName: Full=Serine palmitoyltransferase 1;
DE EC=2.3.1.50 {ECO:0000250|UniProtKB:O15269};
DE AltName: Full=Long chain base biosynthesis protein 1;
DE Short=LCB 1;
DE AltName: Full=Serine-palmitoyl-CoA transferase 1;
DE Short=SPT 1;
DE Short=SPT1;
GN Name=SPTLC1; Synonyms=LCB1;
OS Cricetulus griseus (Chinese hamster) (Cricetulus barabensis griseus).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; Muroidea;
OC Cricetidae; Cricetinae; Cricetulus.
OX NCBI_TaxID=10029;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Ovary;
RX PubMed=9405408; DOI=10.1074/jbc.272.51.32108;
RA Hanada K., Hara T., Nishijima M., Kuge O., Dickson R.C., Nagiec M.M.;
RT "A mammalian homolog of the yeast LCB1 encodes a component of serine
RT palmitoyltransferase, the enzyme catalyzing the first step in sphingolipid
RT synthesis.";
RL J. Biol. Chem. 272:32108-32114(1997).
RN [2]
RP SUBCELLULAR LOCATION, AND MEMBRANE TOPOLOGY.
RX PubMed=12464627; DOI=10.1074/jbc.m209602200;
RA Yasuda S., Nishijima M., Hanada K.;
RT "Localization, topology, and function of the LCB1 subunit of serine
RT palmitoyltransferase in mammalian cells.";
RL J. Biol. Chem. 278:4176-4183(2003).
CC -!- FUNCTION: Serine palmitoyltransferase (SPT). The heterodimer formed
CC with SPTLC2 or SPTLC3 constitutes the catalytic core. The composition
CC of the serine palmitoyltransferase (SPT) complex determines the
CC substrate preference. The SPTLC1-SPTLC2-SPTSSA complex shows a strong
CC preference for C16-CoA substrate, while the SPTLC1-SPTLC3-SPTSSA
CC isozyme uses both C14-CoA and C16-CoA as substrates, with a slight
CC preference for C14-CoA. The SPTLC1-SPTLC2-SPTSSB complex shows a strong
CC preference for C18-CoA substrate, while the SPTLC1-SPTLC3-SPTSSB
CC isozyme displays an ability to use a broader range of acyl-CoAs,
CC without apparent preference (By similarity). Required for adipocyte
CC cell viability and metabolic homeostasis (By similarity).
CC {ECO:0000250|UniProtKB:O15269, ECO:0000250|UniProtKB:O35704}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=H(+) + hexadecanoyl-CoA + L-serine = 3-oxosphinganine + CO2 +
CC CoA; Xref=Rhea:RHEA:14761, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526,
CC ChEBI:CHEBI:33384, ChEBI:CHEBI:57287, ChEBI:CHEBI:57379,
CC ChEBI:CHEBI:58299; EC=2.3.1.50;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:14762;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=H(+) + L-serine + octadecanoyl-CoA = 3-oxoeicosasphinganine +
CC CO2 + CoA; Xref=Rhea:RHEA:33683, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:16526, ChEBI:CHEBI:33384, ChEBI:CHEBI:57287,
CC ChEBI:CHEBI:57394, ChEBI:CHEBI:65073;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:33684;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=H(+) + L-serine + tetradecanoyl-CoA = 3-oxohexadecasphinganine
CC + CO2 + CoA; Xref=Rhea:RHEA:35675, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:16526, ChEBI:CHEBI:33384, ChEBI:CHEBI:57287,
CC ChEBI:CHEBI:57385, ChEBI:CHEBI:71007;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:35676;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=dodecanoyl-CoA + H(+) + L-serine = 3-oxotetradecasphinganine +
CC CO2 + CoA; Xref=Rhea:RHEA:35679, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:16526, ChEBI:CHEBI:33384, ChEBI:CHEBI:57287,
CC ChEBI:CHEBI:57375, ChEBI:CHEBI:71008;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:35680;
CC Evidence={ECO:0000250|UniProtKB:O15269};
CC -!- COFACTOR:
CC Name=pyridoxal 5'-phosphate; Xref=ChEBI:CHEBI:597326;
CC Evidence={ECO:0000250};
CC -!- PATHWAY: Lipid metabolism; sphingolipid metabolism.
CC -!- SUBUNIT: Heterodimer with SPTLC2 or SPTLC3. Component of the serine
CC palmitoyltransferase (SPT) complex, composed of SPTLC1, either SPTLC2
CC or SPTLC3, and either SPTSSA or SPTSSB. The composition of the complex
CC will define the substrate specificity. Interacts with SPTSSA and
CC SPTSSB; the interaction is direct. Interacts with ORMDL3 (By
CC similarity). Interacts with RTN4 (isoform B) (By similarity).
CC {ECO:0000250|UniProtKB:O15269, ECO:0000250|UniProtKB:O35704}.
CC -!- SUBCELLULAR LOCATION: Endoplasmic reticulum membrane
CC {ECO:0000269|PubMed:12464627}; Single-pass membrane protein
CC {ECO:0000269|PubMed:12464627}.
CC -!- PTM: Phosphorylation at Tyr-164 inhibits activity and promotes cell
CC survival. {ECO:0000250|UniProtKB:O15269}.
CC -!- SIMILARITY: Belongs to the class-II pyridoxal-phosphate-dependent
CC aminotransferase family. {ECO:0000305}.
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DR EMBL; AF004831; AAC53505.1; -; mRNA.
DR RefSeq; NP_001233688.1; NM_001246759.1.
DR AlphaFoldDB; O54695; -.
DR SMR; O54695; -.
DR STRING; 10029.NP_001233688.1; -.
DR Ensembl; ENSCGRT00001000975; ENSCGRP00001000951; ENSCGRG00001000731.
DR GeneID; 100689326; -.
DR KEGG; cge:100689326; -.
DR CTD; 10558; -.
DR eggNOG; KOG1358; Eukaryota.
DR GeneTree; ENSGT00550000074872; -.
DR OMA; RNTPTFA; -.
DR OrthoDB; 438936at2759; -.
DR UniPathway; UPA00222; -.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0017059; C:serine C-palmitoyltransferase complex; IDA:MGI.
DR GO; GO:0035339; C:SPOTS complex; ISS:UniProtKB.
DR GO; GO:0030170; F:pyridoxal phosphate binding; IEA:InterPro.
DR GO; GO:0004758; F:serine C-palmitoyltransferase activity; ISS:UniProtKB.
DR GO; GO:0046513; P:ceramide biosynthetic process; IEA:Ensembl.
DR GO; GO:1904504; P:positive regulation of lipophagy; IEA:Ensembl.
DR GO; GO:1904649; P:regulation of fat cell apoptotic process; ISS:UniProtKB.
DR GO; GO:0046511; P:sphinganine biosynthetic process; IEA:Ensembl.
DR GO; GO:0006686; P:sphingomyelin biosynthetic process; IDA:MGI.
DR GO; GO:0046512; P:sphingosine biosynthetic process; IEA:Ensembl.
DR Gene3D; 3.40.640.10; -; 1.
DR Gene3D; 3.90.1150.10; -; 1.
DR InterPro; IPR004839; Aminotransferase_I/II.
DR InterPro; IPR015424; PyrdxlP-dep_Trfase.
DR InterPro; IPR015421; PyrdxlP-dep_Trfase_major.
DR InterPro; IPR015422; PyrdxlP-dep_Trfase_small.
DR Pfam; PF00155; Aminotran_1_2; 1.
DR SUPFAM; SSF53383; SSF53383; 1.
PE 1: Evidence at protein level;
KW Acyltransferase; Endoplasmic reticulum; Lipid metabolism; Membrane;
KW Phosphoprotein; Pyridoxal phosphate; Sphingolipid metabolism; Transferase;
KW Transmembrane; Transmembrane helix.
FT CHAIN 1..473
FT /note="Serine palmitoyltransferase 1"
FT /id="PRO_0000163852"
FT TOPO_DOM 1..15
FT /note="Lumenal"
FT /evidence="ECO:0000255"
FT TRANSMEM 16..36
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 37..473
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT MOD_RES 164
FT /note="Phosphotyrosine; by ABL"
FT /evidence="ECO:0000250|UniProtKB:O15269"
SQ SEQUENCE 473 AA; 52520 MW; 1ABED2B60EC854B4 CRC64;
MAMAAEQWVL VEMVQALYEA PAYHLILEGI LILWIIRLVF SKTYKLQERS DLTAKEKEEL
IEEWQPEPLV PPVSKNHPAL NYNIVSGPPT HNIVVNGKEC VNFASFNFLG LLANPRVKAA
ALASLKKYGV GTCGPRGFYG TFDVHLDLEE RLAKFMRTEE AIIYSYGFST IASAIPAYSK
RGDIVFVDSA ACFAIQKGLQ ASRSDIKLFK HNDVADLERL LKEQEIEDQK NPRKARVTRR
FIVVEGLYMN TGTVCPLPEL VKLKYKYKAR IFLEESLSFG VLGEHGRGVT EHYGISIDDI
DLISANMENA LASVGGFCCG RSFVVDHQRL SGQGYCFSAS LPPLLAAAAI EALNIMEENP
GIFAVLKKKC QHIHKSLQGI SGLKVVGESL SPALHLQLEE STGSREKDVQ LLQEMVIHCM
NEGIALTQAR YLDKEEKCLP PPSIRVVVTV EQTEEELERA ASTIREAAQA VLL
