ID   SPTC3_HUMAN             Reviewed;         552 AA.
AC   Q9NUV7; A2A2I4; B9EK64; Q05DQ8; Q5T1U4; Q9H1L1; Q9H1Z0;
DT   10-OCT-2002, integrated into UniProtKB/Swiss-Prot.
DT   02-OCT-2007, sequence version 3.
DT   27-MAR-2024, entry version 171.
DE   RecName: Full=Serine palmitoyltransferase 3 {ECO:0000305};
DE            EC=2.3.1.50 {ECO:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650};
DE   AltName: Full=Long chain base biosynthesis protein 2b;
DE            Short=LCB2b {ECO:0000303|PubMed:19416851};
DE   AltName: Full=Long chain base biosynthesis protein 3;
DE            Short=LCB 3;
DE   AltName: Full=Serine-palmitoyl-CoA transferase 3;
DE            Short=SPT 3;
GN   Name=SPTLC3 {ECO:0000312|HGNC:HGNC:16253}; Synonyms=C20orf38, SPTLC2L;
OS   Homo sapiens (Human).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae;
OC   Homo.
OX   NCBI_TaxID=9606;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), CATALYTIC ACTIVITY, AND TISSUE
RP   SPECIFICITY.
RX   PubMed=17023427; DOI=10.1074/jbc.m608066200;
RA   Hornemann T., Richard S., Ruetti M.F., Wei Y., von Eckardstein A.;
RT   "Cloning and initial characterization of a new subunit for mammalian
RT   serine-palmitoyltransferase.";
RL   J. Biol. Chem. 281:37275-37281(2006).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2).
RC   TISSUE=Placenta;
RX   PubMed=14702039; DOI=10.1038/ng1285;
RA   Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R.,
RA   Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H.,
RA   Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.,
RA   Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K.,
RA   Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H.,
RA   Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M.,
RA   Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K.,
RA   Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T.,
RA   Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M.,
RA   Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S.,
RA   Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H.,
RA   Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K.,
RA   Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N.,
RA   Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S.,
RA   Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O.,
RA   Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H.,
RA   Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B.,
RA   Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y.,
RA   Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K.,
RA   Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T.,
RA   Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T.,
RA   Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y.,
RA   Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H.,
RA   Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y.,
RA   Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H.,
RA   Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O.,
RA   Isogai T., Sugano S.;
RT   "Complete sequencing and characterization of 21,243 full-length human
RT   cDNAs.";
RL   Nat. Genet. 36:40-45(2004).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RX   PubMed=11780052; DOI=10.1038/414865a;
RA   Deloukas P., Matthews L.H., Ashurst J.L., Burton J., Gilbert J.G.R.,
RA   Jones M., Stavrides G., Almeida J.P., Babbage A.K., Bagguley C.L.,
RA   Bailey J., Barlow K.F., Bates K.N., Beard L.M., Beare D.M., Beasley O.P.,
RA   Bird C.P., Blakey S.E., Bridgeman A.M., Brown A.J., Buck D., Burrill W.D.,
RA   Butler A.P., Carder C., Carter N.P., Chapman J.C., Clamp M., Clark G.,
RA   Clark L.N., Clark S.Y., Clee C.M., Clegg S., Cobley V.E., Collier R.E.,
RA   Connor R.E., Corby N.R., Coulson A., Coville G.J., Deadman R., Dhami P.D.,
RA   Dunn M., Ellington A.G., Frankland J.A., Fraser A., French L., Garner P.,
RA   Grafham D.V., Griffiths C., Griffiths M.N.D., Gwilliam R., Hall R.E.,
RA   Hammond S., Harley J.L., Heath P.D., Ho S., Holden J.L., Howden P.J.,
RA   Huckle E., Hunt A.R., Hunt S.E., Jekosch K., Johnson C.M., Johnson D.,
RA   Kay M.P., Kimberley A.M., King A., Knights A., Laird G.K., Lawlor S.,
RA   Lehvaeslaiho M.H., Leversha M.A., Lloyd C., Lloyd D.M., Lovell J.D.,
RA   Marsh V.L., Martin S.L., McConnachie L.J., McLay K., McMurray A.A.,
RA   Milne S.A., Mistry D., Moore M.J.F., Mullikin J.C., Nickerson T.,
RA   Oliver K., Parker A., Patel R., Pearce T.A.V., Peck A.I.,
RA   Phillimore B.J.C.T., Prathalingam S.R., Plumb R.W., Ramsay H., Rice C.M.,
RA   Ross M.T., Scott C.E., Sehra H.K., Shownkeen R., Sims S., Skuce C.D.,
RA   Smith M.L., Soderlund C., Steward C.A., Sulston J.E., Swann R.M.,
RA   Sycamore N., Taylor R., Tee L., Thomas D.W., Thorpe A., Tracey A.,
RA   Tromans A.C., Vaudin M., Wall M., Wallis J.M., Whitehead S.L.,
RA   Whittaker P., Willey D.L., Williams L., Williams S.A., Wilming L.,
RA   Wray P.W., Hubbard T., Durbin R.M., Bentley D.R., Beck S., Rogers J.;
RT   "The DNA sequence and comparative analysis of human chromosome 20.";
RL   Nature 414:865-871(2001).
RN   [4]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 2), AND VARIANT
RP   VAL-140.
RC   TISSUE=Brain, Placenta, and Urinary bladder;
RX   PubMed=15489334; DOI=10.1101/gr.2596504;
RG   The MGC Project Team;
RT   "The status, quality, and expansion of the NIH full-length cDNA project:
RT   the Mammalian Gene Collection (MGC).";
RL   Genome Res. 14:2121-2127(2004).
RN   [5]
RP   FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES, AND PATHWAY.
RX   PubMed=19648650; DOI=10.1074/jbc.m109.023192;
RA   Hornemann T., Penno A., Ruetti M.F., Ernst D., Kivrak-Pfiffner F.,
RA   Rohrer L., von Eckardstein A.;
RT   "The SPTLC3 subunit of serine palmitoyltransferase generates short chain
RT   sphingoid bases.";
RL   J. Biol. Chem. 284:26322-26330(2009).
RN   [6]
RP   FUNCTION, CATALYTIC ACTIVITY, AND IDENTIFICATION IN THE SPT COMPLEX.
RX   PubMed=19416851; DOI=10.1073/pnas.0811269106;
RA   Han G., Gupta S.D., Gable K., Niranjanakumari S., Moitra P., Eichler F.,
RA   Brown R.H. Jr., Harmon J.M., Dunn T.M.;
RT   "Identification of small subunits of mammalian serine palmitoyltransferase
RT   that confer distinct acyl-CoA substrate specificities.";
RL   Proc. Natl. Acad. Sci. U.S.A. 106:8186-8191(2009).
CC   -!- FUNCTION: Component of the serine palmitoyltransferase multisubunit
CC       enzyme (SPT) that catalyzes the initial and rate-limiting step in
CC       sphingolipid biosynthesis by condensing L-serine and activated acyl-CoA
CC       (most commonly palmitoyl-CoA) to form long-chain bases
CC       (PubMed:19648650, PubMed:19416851). The SPT complex is composed of
CC       SPTLC1, SPTLC2 or SPTLC3 and SPTSSA or SPTSSB. Within this complex, the
CC       heterodimer consisting of SPTLC1 and SPTLC2/SPTLC3 forms the catalytic
CC       core. The composition of the serine palmitoyltransferase (SPT) complex
CC       determines the substrate preference (PubMed:19416851). The SPTLC1-
CC       SPTLC2-SPTSSA complex shows a strong preference for C16-CoA substrate,
CC       while the SPTLC1-SPTLC3-SPTSSA isozyme uses both C14-CoA and C16-CoA as
CC       substrates, with a slight preference for C14-CoA. The SPTLC1-SPTLC2-
CC       SPTSSB complex shows a strong preference for C18-CoA substrate, while
CC       the SPTLC1-SPTLC3-SPTSSB isozyme displays an ability to use a broader
CC       range of acyl-CoAs, without apparent preference (PubMed:19648650,
CC       PubMed:19416851). {ECO:0000269|PubMed:19416851,
CC       ECO:0000269|PubMed:19648650}.
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:0000269|PubMed:17023427, ECO:0000269|PubMed:19416851,
CC         ECO:0000269|PubMed:19648650};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:14762;
CC         Evidence={ECO:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650};
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:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:35680;
CC         Evidence={ECO:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650};
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:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:35676;
CC         Evidence={ECO:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650};
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:0000269|PubMed:19416851};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:33684;
CC         Evidence={ECO:0000269|PubMed:19416851};
CC   -!- COFACTOR:
CC       Name=pyridoxal 5'-phosphate; Xref=ChEBI:CHEBI:597326;
CC         Evidence={ECO:0000250};
CC   -!- ACTIVITY REGULATION: SPT complex catalytic activity is negatively
CC       regulated by ORMDL proteins, including ORMDL3, in the presence of
CC       ceramides (By similarity). This mechanism allows to maintain ceramide
CC       levels at sufficient concentrations for the production of complex
CC       sphingolipids, but which prevents the accumulation of ceramides to
CC       levels that trigger apoptosis (Probable).
CC       {ECO:0000250|UniProtKB:O15270, ECO:0000305}.
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       Kinetic parameters:
CC         KM=0.04 mM for hexadecanoyl-CoA {ECO:0000269|PubMed:19648650};
CC         KM=0.03 mM for tetradecanoyl-CoA {ECO:0000269|PubMed:19648650};
CC         Vmax=120 pmol/min/mg enzyme toward hexadecanoyl-CoA
CC         {ECO:0000269|PubMed:19648650};
CC         Vmax=60 pmol/min/mg enzyme toward tetradecanoyl-CoA
CC         {ECO:0000269|PubMed:19648650};
CC   -!- PATHWAY: Lipid metabolism; sphingolipid metabolism.
CC       {ECO:0000269|PubMed:19416851, ECO:0000269|PubMed:19648650}.
CC   -!- SUBUNIT: Component of the serine palmitoyltransferase (SPT) complex,
CC       which is composed of SPTLC1, SPTLC2 or SPTLC3 and SPTSSA or SPTSSB. The
CC       heterodimer consisting of SPTLC1 and SPTLC2/SPTLC3 forms the catalytic
CC       core of the enzyme, while SPTSSA or SPTSSB subunits determine substrate
CC       specificity (PubMed:19416851). SPT also interacts with ORMDL proteins,
CC       especially ORMDL3, which negatively regulate SPT activity in the
CC       presence of ceramides (By similarity). {ECO:0000250|UniProtKB:O15270,
CC       ECO:0000269|PubMed:19416851}.
CC   -!- INTERACTION:
CC       Q9NUV7; O15269: SPTLC1; NbExp=3; IntAct=EBI-11614219, EBI-1044323;
CC   -!- SUBCELLULAR LOCATION: Endoplasmic reticulum membrane
CC       {ECO:0000305|PubMed:19416851}; Single-pass membrane protein
CC       {ECO:0000305|PubMed:19416851}.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing; Named isoforms=2;
CC       Name=1;
CC         IsoId=Q9NUV7-1; Sequence=Displayed;
CC       Name=2;
CC         IsoId=Q9NUV7-2; Sequence=VSP_028167, VSP_028168;
CC   -!- TISSUE SPECIFICITY: Expressed in most tissues, except peripheral blood
CC       cells and bone marrow, with highest levels in heart, kidney, liver,
CC       uterus and skin. {ECO:0000269|PubMed:17023427}.
CC   -!- SIMILARITY: Belongs to the class-II pyridoxal-phosphate-dependent
CC       aminotransferase family. {ECO:0000305}.
CC   -!- SEQUENCE CAUTION:
CC       Sequence=AAH05205.1; Type=Miscellaneous discrepancy; Note=Contaminating sequence. Potential poly-A sequence.; Evidence={ECO:0000305};
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DR   EMBL; AK001974; BAA92012.1; -; mRNA.
DR   EMBL; AL133331; CAM13116.1; -; Genomic_DNA.
DR   EMBL; AL050320; CAM13116.1; JOINED; Genomic_DNA.
DR   EMBL; AL109983; CAM13116.1; JOINED; Genomic_DNA.
DR   EMBL; AL445589; CAM13116.1; JOINED; Genomic_DNA.
DR   EMBL; AL445589; CAM16427.1; -; Genomic_DNA.
DR   EMBL; AL050320; CAM16427.1; JOINED; Genomic_DNA.
DR   EMBL; AL109983; CAM16427.1; JOINED; Genomic_DNA.
DR   EMBL; AL133331; CAM16427.1; JOINED; Genomic_DNA.
DR   EMBL; AL050320; CAM27358.1; -; Genomic_DNA.
DR   EMBL; AL109983; CAM27358.1; JOINED; Genomic_DNA.
DR   EMBL; AL133331; CAM27358.1; JOINED; Genomic_DNA.
DR   EMBL; AL445589; CAM27358.1; JOINED; Genomic_DNA.
DR   EMBL; AL109983; CAM28300.1; -; Genomic_DNA.
DR   EMBL; AL050320; CAM28300.1; JOINED; Genomic_DNA.
DR   EMBL; AL133331; CAM28300.1; JOINED; Genomic_DNA.
DR   EMBL; AL445589; CAM28300.1; JOINED; Genomic_DNA.
DR   EMBL; BC005205; AAH05205.1; ALT_SEQ; mRNA.
DR   EMBL; BC020656; AAH20656.1; -; mRNA.
DR   EMBL; BC150644; AAI50645.1; -; mRNA.
DR   CCDS; CCDS13115.2; -. [Q9NUV7-1]
DR   RefSeq; NP_060797.2; NM_018327.2. [Q9NUV7-1]
DR   AlphaFoldDB; Q9NUV7; -.
DR   SMR; Q9NUV7; -.
DR   BioGRID; 120590; 11.
DR   ComplexPortal; CPX-6665; Serine palmitoyltransferase complex, SPTLC1-SPTLC3-SPTSSA variant.
DR   ComplexPortal; CPX-6681; Serine palmitoyltransferase complex, SPTLC1-SPTLC3-SPTSSB variant.
DR   CORUM; Q9NUV7; -.
DR   DIP; DIP-60753N; -.
DR   IntAct; Q9NUV7; 5.
DR   STRING; 9606.ENSP00000381968; -.
DR   DrugBank; DB00114; Pyridoxal phosphate.
DR   SwissLipids; SLP:000000153; -.
DR   iPTMnet; Q9NUV7; -.
DR   PhosphoSitePlus; Q9NUV7; -.
DR   SwissPalm; Q9NUV7; -.
DR   BioMuta; SPTLC3; -.
DR   DMDM; 158931158; -.
DR   EPD; Q9NUV7; -.
DR   jPOST; Q9NUV7; -.
DR   MassIVE; Q9NUV7; -.
DR   MaxQB; Q9NUV7; -.
DR   PaxDb; 9606-ENSP00000381968; -.
DR   PeptideAtlas; Q9NUV7; -.
DR   ProteomicsDB; 82722; -. [Q9NUV7-1]
DR   ProteomicsDB; 82723; -. [Q9NUV7-2]
DR   Pumba; Q9NUV7; -.
DR   Antibodypedia; 70994; 68 antibodies from 13 providers.
DR   DNASU; 55304; -.
DR   Ensembl; ENST00000399002.7; ENSP00000381968.2; ENSG00000172296.13. [Q9NUV7-1]
DR   GeneID; 55304; -.
DR   KEGG; hsa:55304; -.
DR   MANE-Select; ENST00000399002.7; ENSP00000381968.2; NM_018327.4; NP_060797.2.
DR   UCSC; uc002wod.2; human. [Q9NUV7-1]
DR   AGR; HGNC:16253; -.
DR   CTD; 55304; -.
DR   DisGeNET; 55304; -.
DR   GeneCards; SPTLC3; -.
DR   HGNC; HGNC:16253; SPTLC3.
DR   HPA; ENSG00000172296; Low tissue specificity.
DR   MIM; 611120; gene.
DR   neXtProt; NX_Q9NUV7; -.
DR   OpenTargets; ENSG00000172296; -.
DR   PharmGKB; PA162404677; -.
DR   VEuPathDB; HostDB:ENSG00000172296; -.
DR   eggNOG; KOG1357; Eukaryota.
DR   GeneTree; ENSGT00940000158513; -.
DR   HOGENOM; CLU_015846_7_1_1; -.
DR   InParanoid; Q9NUV7; -.
DR   OMA; FCVSNHP; -.
DR   OrthoDB; 9643at2759; -.
DR   PhylomeDB; Q9NUV7; -.
DR   TreeFam; TF300452; -.
DR   BioCyc; MetaCyc:HS16070-MONOMER; -.
DR   BRENDA; 2.3.1.50; 2681.
DR   PathwayCommons; Q9NUV7; -.
DR   Reactome; R-HSA-1660661; Sphingolipid de novo biosynthesis.
DR   SignaLink; Q9NUV7; -.
DR   UniPathway; UPA00222; -.
DR   BioGRID-ORCS; 55304; 7 hits in 1155 CRISPR screens.
DR   GenomeRNAi; 55304; -.
DR   Pharos; Q9NUV7; Tbio.
DR   PRO; PR:Q9NUV7; -.
DR   Proteomes; UP000005640; Chromosome 20.
DR   RNAct; Q9NUV7; Protein.
DR   Bgee; ENSG00000172296; Expressed in buccal mucosa cell and 155 other cell types or tissues.
DR   ExpressionAtlas; Q9NUV7; baseline and differential.
DR   GO; GO:0005789; C:endoplasmic reticulum membrane; TAS:Reactome.
DR   GO; GO:0017059; C:serine C-palmitoyltransferase complex; IDA:UniProtKB.
DR   GO; GO:0030170; F:pyridoxal phosphate binding; IEA:InterPro.
DR   GO; GO:0004758; F:serine C-palmitoyltransferase activity; IDA:UniProtKB.
DR   GO; GO:0046513; P:ceramide biosynthetic process; IBA:GO_Central.
DR   GO; GO:0046520; P:sphingoid biosynthetic process; IDA:MGI.
DR   GO; GO:0030148; P:sphingolipid biosynthetic process; TAS:UniProtKB.
DR   GO; GO:0046512; P:sphingosine biosynthetic process; IDA:ComplexPortal.
DR   CDD; cd06454; KBL_like; 1.
DR   Gene3D; 3.90.1150.10; Aspartate Aminotransferase, domain 1; 1.
DR   Gene3D; 3.40.640.10; Type I PLP-dependent aspartate aminotransferase-like (Major domain); 1.
DR   InterPro; IPR001917; Aminotrans_II_pyridoxalP_BS.
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   PANTHER; PTHR13693; CLASS II AMINOTRANSFERASE/8-AMINO-7-OXONONANOATE SYNTHASE; 1.
DR   PANTHER; PTHR13693:SF56; SERINE PALMITOYLTRANSFERASE 3; 1.
DR   Pfam; PF00155; Aminotran_1_2; 1.
DR   SUPFAM; SSF53383; PLP-dependent transferases; 1.
DR   PROSITE; PS00599; AA_TRANSFER_CLASS_2; 1.
DR   Genevisible; Q9NUV7; HS.
PE   1: Evidence at protein level;
KW   Acyltransferase; Alternative splicing; Endoplasmic reticulum;
KW   Lipid metabolism; Membrane; Pyridoxal phosphate; Reference proteome;
KW   Sphingolipid metabolism; Transferase; Transmembrane; Transmembrane helix.
FT   CHAIN           1..552
FT                   /note="Serine palmitoyltransferase 3"
FT                   /id="PRO_0000079426"
FT   TRANSMEM        59..79
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   REGION          1..29
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   COMPBIAS        15..29
FT                   /note="Polar residues"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   MOD_RES         371
FT                   /note="N6-(pyridoxal phosphate)lysine"
FT                   /evidence="ECO:0000250"
FT   VAR_SEQ         102..175
FT                   /note="DFVPLYQDFENFYTRNLYMRIRDNWNRPICSAPGPLFDLMERVSDDYNWTFR
FT                   FTGRVIKDVINMGSYNFLGLAA -> VRMRTSLDLCQCLLLSKVFSEVVMQVQILESMR
FT                   CSGTIQGKFHSSPPPKPHYPWAYGPVFTNISWATTICHIPN (in isoform 2)"
FT                   /evidence="ECO:0000303|PubMed:14702039,
FT                   ECO:0000303|PubMed:15489334"
FT                   /id="VSP_028167"
FT   VAR_SEQ         176..552
FT                   /note="Missing (in isoform 2)"
FT                   /evidence="ECO:0000303|PubMed:14702039,
FT                   ECO:0000303|PubMed:15489334"
FT                   /id="VSP_028168"
FT   VARIANT         140
FT                   /note="L -> V (in dbSNP:rs243887)"
FT                   /evidence="ECO:0000269|PubMed:15489334"
FT                   /id="VAR_048230"
FT   VARIANT         Q9NUV7-2:149
FT                   /note="P -> A (in dbSNP:rs934335)"
FT                   /evidence="ECO:0000305"
FT                   /id="VAR_082794"
SQ   SEQUENCE   552 AA;  62049 MW;  EED341220DCA683A CRC64;
     MANPGGGAVC NGKLHNHKKQ SNGSQSRNCT KNGIVKEAQQ NGKPHFYDKL IVESFEEAPL
     HVMVFTYMGY GIGTLFGYLR DFLRNWGIEK CNAAVERKEQ KDFVPLYQDF ENFYTRNLYM
     RIRDNWNRPI CSAPGPLFDL MERVSDDYNW TFRFTGRVIK DVINMGSYNF LGLAAKYDES
     MRTIKDVLEV YGTGVASTRH EMGTLDKHKE LEDLVAKFLN VEAAMVFGMG FATNSMNIPA
     LVGKGCLILS DELNHTSLVL GARLSGATIR IFKHNNTQSL EKLLRDAVIY GQPRTRRAWK
     KILILVEGVY SMEGSIVHLP QIIALKKKYK AYLYIDEAHS IGAVGPTGRG VTEFFGLDPH
     EVDVLMGTFT KSFGASGGYI AGRKDLVDYL RVHSHSAVYA SSMSPPIAEQ IIRSLKLIMG
     LDGTTQGLQR VQQLAKNTRY FRQRLQEMGF IIYGNENASV VPLLLYMPGK VAAFARHMLE
     KKIGVVVVGF PATPLAEARA RFCVSAAHTR EMLDTVLEAL DEMGDLLQLK YSRHKKSARP
     ELYDETSFEL ED
//