Protein: Ceramide synthase LAG1 (Longevity assurance factor 1) (Longevity assurance gene 1 protein) (Longevity assurance protein 1) (Very-long-chain ceramide synthase LAG1) (EC 2.3.1.297) (P38703)
Organism: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
Function: Component of the ceramide synthase complex that catalyzes the transfer of the acyl chain from acyl-CoA to a sphingoid base, with high selectivity toward hexacosanoyl-CoA (C26:0-CoA). N-acylates sphinganine and phytosphingosine bases to form dihydroceramides and phytoceramides, respectively. Redundant with LAC1. Facilitates ER-to-Golgi transport of GPI-anchored proteins. Involved in the aging process. Deletion of LAG1 results in a pronounced increase (approximately 50%) in mean and in maximum life span.
Subcellular location: Endoplasmic reticulum membrane {ECO:0000250}; Multi-pass membrane protein {ECO:0000250}.
Sequence: MTSATDKSIDRLVVNAKTRRRNSSVGKIDLGDTVPGFAAMPESAASKNEAKKRMKALTGDSKKDSDLLWKVWFSYREMNYRHSWLTPFFILVCVYSAYFLSGNRTESNPLHMFVAISYQVDGTDSYAKGIKDLSFVFFYMIFFTFLREFLMDVVIRPFTVYLNVTSEHRQKRMLEQMYAIFYCGVSGPFGLYIMYHSDLWLFKTKPMYRTYPVITNPFLFKIFYLGQAAFWAQQACVLVLQLEKPRKDYKELVFHHIVTLLLIWSSYVFHFTKMGLAIYITMDVSDFFLSLSKTLNYLNSVFTPFVFGLFVFFWIYLRHVVNIRILWSVLTEFRHEGNYVLNFATQQYKCWISLPIVFVLIAALQLVNLYWLFLILRILYRLIWQGIQKDERSDSDSDESAENEESKEKCE
InterPro domains: - IPR006634: TRAM/LAG1/CLN8 homology domain (domain) [168-384]
- IPR016439: Sphingosine N-acyltransferase Lag1/Lac1-like (family) [82-404]
Interaction partners: - Ceramide synthase subunit LIP1
- Alkaline ceramidase YDC1
- Alkaline ceramidase YPC1
- Ceramide synthase LAC1
- Sphingoid long chain base kinase 4
- Dihydrosphingosine 1-phosphate phosphatase LCB3
- 3-ketodihydrosphingosine reductase TSC10
- Sphingolipid C4-hydroxylase SUR2
- Sphingoid long chain base kinase 5
- Dihydrosphingosine 1-phosphate phosphatase YSR3
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0003824 (catalytic activity), GO:0016740 (transferase activity), GO:0005515 (protein binding), GO:0016746 (acyltransferase activity), GO:0016747 (acyltransferase activity, transferring groups other than amino-acyl groups), GO:0016410 (N-acyltransferase activity)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0009987 (cellular process), GO:0009058 (biosynthetic process), GO:0044237 (cellular metabolic process), GO:0071704 (organic substance metabolic process), GO:0044238 (primary metabolic process), GO:0006807 (nitrogen compound metabolic process), GO:0044255 (cellular lipid metabolic process), GO:0044249 (cellular biosynthetic process), GO:0034641 (cellular nitrogen compound metabolic process), GO:0043603 (amide metabolic process), GO:1901576 (organic substance biosynthetic process), GO:1901564 (organonitrogen compound metabolic process), GO:0006629 (lipid metabolic process), GO:1901566 (organonitrogen compound biosynthetic process), GO:0006672 (ceramide metabolic process), GO:0043604 (amide biosynthetic process), GO:0006665 (sphingolipid metabolic process), GO:0044271 (cellular nitrogen compound biosynthetic process), GO:0046467 (membrane lipid biosynthetic process), GO:0008610 (lipid biosynthetic process), GO:0006643 (membrane lipid metabolic process), GO:0046513 (ceramide biosynthetic process), GO:0030148 (sphingolipid biosynthetic process)
Cellular Component (CC): GO:0005575 (cellular component), GO:0032991 (protein-containing complex), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0031974 (membrane-enclosed lumen), GO:1902494 (catalytic complex), GO:0034399 (nuclear periphery), GO:0005737 (cytoplasm), GO:0012505 (endomembrane system), GO:0043233 (organelle lumen), GO:0005783 (endoplasmic reticulum), GO:0043229 (intracellular organelle), GO:0043227 (membrane-bounded organelle), GO:0043231 (intracellular membrane-bounded organelle), GO:0070013 (intracellular organelle lumen), GO:0031981 (nuclear lumen), GO:0005634 (nucleus)