LAC1 BASIC INFORMATION
| Standard Name | LAC1 |
|---|---|
| Systematic Name | YKL008C |
| Alias | DGT1 |
| Feature Type | ORF, Verified |
| Description | Ceramide synthase component, involved in synthesis of ceramide from C26(acyl)-coenzyme A and dihydrosphingosine or phytosphingosine, functionally equivalent to Lag1p (1 and see Summary Paragraph)
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| Name Description | Longevity-Assurance gene Cognate (LAG1 Cognate) 2 |
| GO Annotations | All LAC1 GO evidence and references |
|---|---|
| View Computational GO annotations for LAC1 | |
| Molecular Function | |
| Manually curated | |
| Biological Process | |
| Manually curated | |
| Cellular Component | |
| Manually curated |
| Pathways |
|---|
| Mutant Phenotype | All LAC1 Phenotype details and references |
|---|---|
| Large-scale survey | |
| null |
| Interactions | LAC1 All interactions details and references |
|---|---|
| 66 total interaction(s) for 42 unique genes/features. | |
| Physical Interactions |
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| Genetic Interactions |
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| External Links | All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | UniProtKB |
|---|
| Primary SGDID | S000001491 |
|---|
ADDITIONAL INFORMATION for LAC1
SUMMARY PARAGRAPH for LAC1
LAC1 was identified as a close homolog of LAG1, a gene whose expression decreases with increasing age of yeast cells (2). A null lac1 mutant is viable, but a lac1 lag1 double deletion has been reported as lethal (2) or poor-growing (3). Human and C. elegans homologs of LAG1 have been cloned, and each is able to complement a lac1 lag1 double deletion (2). Lac1p and Lag1p have been localized to the endoplasmic reticulum, and are thought to play a role in the transport from the ER to the Golgi of glycosylphosphatidylinositol (GPI)-anchored proteins (3). LAC1 has also been called DGT1 (for "delayed GPI-anchored protein transport," 3), but is not the same as the gene on chromsome IV, MTH1, which has also been called DGT1 (for "decreasing glucose transport").
About sphingolipid metabolism
Sphingolipids are essential components of the plasma membrane in all eukaryotic cells. S. cerevisiae cells make three complex sphingolipids: inositol-phosphoceramide (IPC), mannose-inositol-phosphoceramide (MIPC), and mannose-(inositol phosphate)2-ceramide (M(IP)2C)(4). In the yeast plasma membrane sphingolipids concentrate with ergosterol to form lipid rafts, specialized membrane microdomains implicated in a variety of cellular processes, including sorting of membrane proteins and lipids, as well as organizing and regulating signaling cascades (5). Intermediates in sphingolipid biosynthesis have been shown to play important roles as signaling molecules and growth regulators. Sphingolipid long chain bases (LCBs), dihydrosphingosine (DHS) and phytosphingosine (PHS), have been implicated as secondary messengers in signaling pathways that regulate heat stress response (6, 7). Other intermediates, phytoceramide and long-chain base phosphates (LCBPs), have been shown to be components of the tightly-controlled ceramide/LCBP rheostat, which regulates cell growth (8). Since phosphoinositol-containing sphingolipids are unique to fungi, the sphingolipid biosynthesis pathway is considered a target for antifungal drugs (9, 10).
REFERENCES CITED ON THIS PAGE [View Complete Literature Guide for LAC1]
| 1) | Jazwinski SM (2002) Growing old: metabolic control and yeast aging. Annu Rev Microbiol 56:769-92 |
| 2) | Jiang JC, et al. (1998) Homologs of the yeast longevity gene LAG1 in Caenorhabditis elegans and human. Genome Res 8(12):1259-72 |
| 3) | Barz WP and Walter P (1999) Two endoplasmic reticulum (ER) membrane proteins that facilitate ER-to-Golgi transport of glycosylphosphatidylinositol-anchored proteins. Mol Biol Cell 10(4):1043-59 |
| 4) | Dickson RC and Lester RL (2002) Sphingolipid functions in Saccharomyces cerevisiae. Biochim Biophys Acta 1583(1):13-25 |
| 5) | Bagnat M and Simons K (2002) Lipid rafts in protein sorting and cell polarity in budding yeast Saccharomyces cerevisiae. Biol Chem 383(10):1475-80 |
| 6) | Jenkins GM, et al. (1997) Involvement of yeast sphingolipids in the heat stress response of Saccharomyces cerevisiae. J Biol Chem 272(51):32566-72 |
| 7) | Ferguson-Yankey SR, et al. (2002) Mutant analysis reveals complex regulation of sphingolipid long chain base phosphates and long chain bases during heat stress in yeast. Yeast 19(7):573-86 |
| 8) | Kobayashi SD and Nagiec MM (2003) Ceramide/long-chain base phosphate rheostat in Saccharomyces cerevisiae: regulation of ceramide synthesis by Elo3p and Cka2p. Eukaryot Cell 2(2):284-94 |
| 9) | Nagiec MM, et al. (1997) Sphingolipid synthesis as a target for antifungal drugs. Complementation of the inositol phosphorylceramide synthase defect in a mutant strain of Saccharomyces cerevisiae by the AUR1 gene. J Biol Chem 272(15):9809-17 |
| 10) | Sugimoto Y, et al. (2004) IPC synthase as a useful target for antifungal drugs. Curr Drug Targets Infect Disord 4(4):311-22 |




