Activation of long-chain fatty acids for both synthesis of cellular lipids, and degradation via beta-oxidation. Preferentially uses arachidonate and eicosapentaenoate as substrates.
Long-chain fatty acid-CoA ligase (also called fatty acid acyl-CoA synthetase) plays an essential role in lipid biosynthesis and fatty acid degradation. We report herein the cDNA cloning of the human long-chain fatty acid-CoA ligase 4 from a brain library. The cDNA encodes a functional long-chain fatty acid-CoA ligase that shows preference for arachidonic acid as substrate. We also studied the tissue distribution of gene expression by Northern hybridization. Human placenta, brain, testis, ovary, spleen, and adrenal cortex have the highest levels of expression of the long-chain fatty acid-CoA ligase 4, whereas the GI system has the lowest. Finally, this gene was localized to chromosome Xq23 in human by FISH analysis.
Evidence
2:
Inferred from Direct AssayUniProtKB
Evidence for Short
Long-chain acyl-CoA synthetases (ACSLs) catalyze the thioesterification of long-chain FAs into their acyl-CoA derivatives. Purified ACSL4 is an arachidonic acid (20:4)-preferring ACSL isoform, and ACSL4 is therefore a probable regulator of lipid mediator production in intact cells. Eicosanoids play important roles in vascular homeostasis and disease, yet the role of ACSL4 in vascular cells is largely unknown. In the present study, the ACSL4 splice variant expressed in human arterial smooth muscle cells (SMCs) was identified as variant 1. To investigate the function of ACSL4 in SMCs, ACSL4 variant 1 was overexpressed, knocked-down by small interfering RNA, or its enzymatic activity acutely inhibited in these cells. Overexpression of ACSL4 resulted in a markedly increased synthesis of arachidonoyl-CoA, increased 20:4 incorporation into phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol, and reduced cellular levels of unesterified 20:4. Accordingly, secretion of prostaglandin E₂ (PGE₂) was blunted in ACSL4-overexpressing SMCs compared with controls. Conversely, acute pharmacological inhibition of ACSL4 activity resulted in increased release of PGE₂. However, long-term downregulation of ACSL4 resulted in markedly reduced PGE₂ secretion. Thus, ACSL4 modulates PGE₂ release from human SMCs. ACSL4 may regulate a number of processes dependent on the release of arachidonic acid-derived lipid mediators in the arterial wall.
Catalysis of the reaction: ATP + a long-chain carboxylic acid + CoA = AMP + diphosphate + an acyl-CoA; a long-chain fatty acid is a fatty acid with a chain length between C13 and C22.
The roles of phosphoinositide 3-kinase (PI3K) and phospholipase C (PLC) in chemoattractant-elicited responses were studied in mice lacking these key enzymes. PI3Kgamma was required for chemoattractant-induced production of phosphatidylinositol 3,4,5-trisphosphate [PtdIns (3,4,5)P3] and has an important role in chemoattractant-induced superoxide production and chemotaxis in mouse neutrophils and in production of T cell-independent antigen-specific antibodies composed of the immunoglobulin lambda light chain (TI-IglambdaL). The study of the mice lacking PLC-beta2 and -beta3 revealed that the PLC pathways have an important role in chemoattractant-mediated production of superoxide and regulation of protein kinases, but not chemotaxis. The PLC pathways also appear to inhibit the chemotactic activity induced by certain chemoattractants and to suppress TI-IglambdaL production.
Evidence
2:
Inferred from Direct AssayUniProtKB
Evidence for Short
Long-chain acyl-CoA synthetases (ACSLs) catalyze the thioesterification of long-chain FAs into their acyl-CoA derivatives. Purified ACSL4 is an arachidonic acid (20:4)-preferring ACSL isoform, and ACSL4 is therefore a probable regulator of lipid mediator production in intact cells. Eicosanoids play important roles in vascular homeostasis and disease, yet the role of ACSL4 in vascular cells is largely unknown. In the present study, the ACSL4 splice variant expressed in human arterial smooth muscle cells (SMCs) was identified as variant 1. To investigate the function of ACSL4 in SMCs, ACSL4 variant 1 was overexpressed, knocked-down by small interfering RNA, or its enzymatic activity acutely inhibited in these cells. Overexpression of ACSL4 resulted in a markedly increased synthesis of arachidonoyl-CoA, increased 20:4 incorporation into phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol, and reduced cellular levels of unesterified 20:4. Accordingly, secretion of prostaglandin E₂ (PGE₂) was blunted in ACSL4-overexpressing SMCs compared with controls. Conversely, acute pharmacological inhibition of ACSL4 activity resulted in increased release of PGE₂. However, long-term downregulation of ACSL4 resulted in markedly reduced PGE₂ secretion. Thus, ACSL4 modulates PGE₂ release from human SMCs. ACSL4 may regulate a number of processes dependent on the release of arachidonic acid-derived lipid mediators in the arterial wall.
Catalysis of the reaction: ATP + a very-long-chain carboxylic acid + CoA = AMP + diphosphate + an acyl-CoA; a very long-chain fatty acid is a fatty acid which has a chain length greater than C22.
Evidence
1:
Inferred from Mutant PhenotypeUniProtKB
X-linked mental retardation (XLMR) is an inherited condition that causes failure to develop cognitive abilities, owing to mutations in a gene on the X chromosome. The latest XLMR update lists up to 136 conditions leading to 'syndromic', or 'specific', mental retardation (MRXS) and 66 entries leading to 'nonspecific' mental retardation (MRX). For 9 of the 66 MRX entries, the causative gene has been identified. Our recent discovery of the contiguous gene deletion syndrome ATS-MR (previously known as Alport syndrome, mental retardation, midface hypoplasia, elliptocytosis, OMIM #300194), characterized by Alport syndrome (ATS) and mental retardation (MR), indicated Xq22.3 as a region containing one mental retardation gene. Comparing the extent of deletion between individuals with ATS-MR and individuals with ATS alone allowed us to define a critical region for mental retardation of approximately 380 kb, containing four genes. Here we report the identification of two point mutations, one missense and one splice-site change, in the gene FACL4 in two families with nonspecific mental retardation. Analysis of enzymatic activity in lymphoblastoid cell lines from affected individuals of both families revealed low levels compared with normal cells, indicating that both mutations are null mutations. All carrier females with either point mutations or genomic deletions in FACL4 showed a completely skewed X-inactivation, suggesting that the gene influences survival advantage. FACL4 is the first gene shown to be involved in nonspecific mental retardation and fatty-acid metabolism.
The process whose specific outcome is the progression of the dendritic spine over time, from its formation to the mature structure. A dendritic spine is a protrusion from a dendrite and a specialized subcellular compartment involved in synaptic transmission.
The directed movement of fatty acids into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. Fatty acids are aliphatic monocarboxylic acids liberated from naturally occurring fats and oils by hydrolysis.
The chemical reactions and pathways resulting in the formation of lipids, compounds soluble in an organic solvent but not, or sparingly, in an aqueous solvent.
Long-chain acyl-CoA synthetases (ACSLs) catalyze the thioesterification of long-chain FAs into their acyl-CoA derivatives. Purified ACSL4 is an arachidonic acid (20:4)-preferring ACSL isoform, and ACSL4 is therefore a probable regulator of lipid mediator production in intact cells. Eicosanoids play important roles in vascular homeostasis and disease, yet the role of ACSL4 in vascular cells is largely unknown. In the present study, the ACSL4 splice variant expressed in human arterial smooth muscle cells (SMCs) was identified as variant 1. To investigate the function of ACSL4 in SMCs, ACSL4 variant 1 was overexpressed, knocked-down by small interfering RNA, or its enzymatic activity acutely inhibited in these cells. Overexpression of ACSL4 resulted in a markedly increased synthesis of arachidonoyl-CoA, increased 20:4 incorporation into phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol, and reduced cellular levels of unesterified 20:4. Accordingly, secretion of prostaglandin E₂ (PGE₂) was blunted in ACSL4-overexpressing SMCs compared with controls. Conversely, acute pharmacological inhibition of ACSL4 activity resulted in increased release of PGE₂. However, long-term downregulation of ACSL4 resulted in markedly reduced PGE₂ secretion. Thus, ACSL4 modulates PGE₂ release from human SMCs. ACSL4 may regulate a number of processes dependent on the release of arachidonic acid-derived lipid mediators in the arterial wall.
The chemical reactions and pathways involving lipids, compounds soluble in an organic solvent but not, or sparingly, in an aqueous solvent. Includes fatty acids; neutral fats, other fatty-acid esters, and soaps; long-chain (fatty) alcohols and waxes; sphingoids and other long-chain bases; glycolipids, phospholipids and sphingolipids; and carotenes, polyprenols, sterols, terpenes and other isoprenoids.
Long-chain fatty acid-CoA ligase (also called fatty acid acyl-CoA synthetase) plays an essential role in lipid biosynthesis and fatty acid degradation. We report herein the cDNA cloning of the human long-chain fatty acid-CoA ligase 4 from a brain library. The cDNA encodes a functional long-chain fatty acid-CoA ligase that shows preference for arachidonic acid as substrate. We also studied the tissue distribution of gene expression by Northern hybridization. Human placenta, brain, testis, ovary, spleen, and adrenal cortex have the highest levels of expression of the long-chain fatty acid-CoA ligase 4, whereas the GI system has the lowest. Finally, this gene was localized to chromosome Xq23 in human by FISH analysis.
Long-chain acyl-CoA synthetases (ACSLs) catalyze the thioesterification of long-chain FAs into their acyl-CoA derivatives. Purified ACSL4 is an arachidonic acid (20:4)-preferring ACSL isoform, and ACSL4 is therefore a probable regulator of lipid mediator production in intact cells. Eicosanoids play important roles in vascular homeostasis and disease, yet the role of ACSL4 in vascular cells is largely unknown. In the present study, the ACSL4 splice variant expressed in human arterial smooth muscle cells (SMCs) was identified as variant 1. To investigate the function of ACSL4 in SMCs, ACSL4 variant 1 was overexpressed, knocked-down by small interfering RNA, or its enzymatic activity acutely inhibited in these cells. Overexpression of ACSL4 resulted in a markedly increased synthesis of arachidonoyl-CoA, increased 20:4 incorporation into phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol, and reduced cellular levels of unesterified 20:4. Accordingly, secretion of prostaglandin E₂ (PGE₂) was blunted in ACSL4-overexpressing SMCs compared with controls. Conversely, acute pharmacological inhibition of ACSL4 activity resulted in increased release of PGE₂. However, long-term downregulation of ACSL4 resulted in markedly reduced PGE₂ secretion. Thus, ACSL4 modulates PGE₂ release from human SMCs. ACSL4 may regulate a number of processes dependent on the release of arachidonic acid-derived lipid mediators in the arterial wall.
Long-chain acyl-CoA synthetases (ACSLs) catalyze the thioesterification of long-chain FAs into their acyl-CoA derivatives. Purified ACSL4 is an arachidonic acid (20:4)-preferring ACSL isoform, and ACSL4 is therefore a probable regulator of lipid mediator production in intact cells. Eicosanoids play important roles in vascular homeostasis and disease, yet the role of ACSL4 in vascular cells is largely unknown. In the present study, the ACSL4 splice variant expressed in human arterial smooth muscle cells (SMCs) was identified as variant 1. To investigate the function of ACSL4 in SMCs, ACSL4 variant 1 was overexpressed, knocked-down by small interfering RNA, or its enzymatic activity acutely inhibited in these cells. Overexpression of ACSL4 resulted in a markedly increased synthesis of arachidonoyl-CoA, increased 20:4 incorporation into phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol, and reduced cellular levels of unesterified 20:4. Accordingly, secretion of prostaglandin E₂ (PGE₂) was blunted in ACSL4-overexpressing SMCs compared with controls. Conversely, acute pharmacological inhibition of ACSL4 activity resulted in increased release of PGE₂. However, long-term downregulation of ACSL4 resulted in markedly reduced PGE₂ secretion. Thus, ACSL4 modulates PGE₂ release from human SMCs. ACSL4 may regulate a number of processes dependent on the release of arachidonic acid-derived lipid mediators in the arterial wall.
Fatty acid-CoA ligase 4 (FACL4) is a central enzyme controlling the unesterified free arachidonic acid (AA) level in cells and the free AA is known to induce apoptosis. We have recently reported that expression of FACL4 is upregulated in about 40% of human hepatocellular carcinoma (HCC) and 50% of HCC cell lines, suggesting that FACL4 may be involved in liver carcinogenesis. In this study, we investigated whether HCC cell growth is regulated by FACL4. Immunoblot analysis showed that SNU 398 cells express very low or no detectable level of FACL4. We, therefore, transfected the SNU 398 cells with FACL4 expression vector, and clones expressing FACL4 were pooled and analyzed. We found that forced expression of FACL4 in SNU 398 promotes the growth of cells. In addition, we observed that triacsin C, a FACL4 inhibitor, inhibits the growth of Hep 3B cell line which expresses high level of endogenous FACL4. We also found that the triacsin C-mediated growth inhibition in Hep 3B cells results from the induction of apoptosis with evidence of Bcl-2 reduction. Altogether, our data show that FACL4 affects HCC cell growth and suggest that modulation of FACL4 expression/activity is an approach for treatment of HCC.
Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of an interleukin-15 stimulus.
Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a nutrient stimulus.
IEAOrtholog Compara
Enzymatic activity
This protein acts as an enzyme. It is known to catalyze the following reaction
EC 6.2.1.3: ATP + a long-chain fatty acid + CoA ⇄ AMP + diphosphate + an acyl-CoA.
Protein involved in the biochemical reactions with fatty acids. Fatty acids are long chain organic acids of the general formula CH3(CnHx)COOH. They are constituents of lipids and can be saturated or unsaturated. The esterified forms are important both as energy storage molecules and structural molecules.
Protein involved in the biochemical reactions of lipids. Lipids are a diverse class of compounds which are insoluble in water but soluble in organic solvents. They include fats, oils, triacylglycerols, fatty acids, glycolipids, phospholipids and steroids.
Enzyme that catalyzes the joining of two molecules coupled with the breakdown of a pyrophosphate bond in ATP or a similar triphosphate. Sometimes the terms "synthase", "synthetase" or "carboxylase" are also used for this class of enzymes.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.