Fatty Acid Synthase, Type II
Fatty Acid Synthases
Fatty Acids
Fatty Acid Synthase, Type I
Nitric Oxide Synthase Type II
Nitric Oxide Synthase
Cerulenin
Nitric Oxide
Fatty Acids, Unsaturated
Fatty Acids, Omega-3
Fatty Acids, Nonesterified
Fatty Acid Synthesis Inhibitors
Sterol Regulatory Element Binding Protein 1
Comparison of the backbone dynamics of the apo- and holo-carboxy-terminal domain of the biotin carboxyl carrier subunit of Escherichia coli acetyl-CoA carboxylase. (1/158)
The biotin carboxyl carrier protein (BCCP) is a subunit of acetyl-CoA carboxylase, a biotin-dependent enzyme that catalyzes the first committed step of fatty acid biosynthesis. In its functional cycle, this protein engages in heterologous protein-protein interactions with three distinct partners, depending on its state of post-translational modification. Apo-BCCP interacts specifically with the biotin holoenzyme synthetase, BirA, which results in the post-translational attachment of biotin to a single lysine residue on BCCP. Holo-BCCP then interacts with the biotin carboxylase subunit of acetyl-CoA carboxylase, which leads to the addition of the carboxylate group of bicarbonate to biotin. Finally, the carboxy-biotinylated form of BCCP interacts with transcarboxylase in the transfer of the carboxylate to acetyl-CoA to form malonyl-CoA. The determinants of protein-protein interaction specificity in this system are unknown. The NMR solution structure of the unbiotinylated form of an 87 residue C-terminal domain fragment (residue 70-156) of BCCP (holoBCCP87) and the crystal structure of the biotinylated form of a C-terminal fragment (residue 77-156) of BCCP from Escherichia coli acetyl-CoA carboxylase have previously been determined. Comparative analysis of these structures provided evidence for small, localized conformational changes in the biotin-binding region upon biotinylation of the protein. These structural changes may be important for regulating specific protein-protein interactions. Since the dynamic properties of proteins are correlated with local structural environments, we have determined the relaxation parameters of the backbone 15N nuclear spins of holoBCCP87, and compared these with the data obtained for the apo protein. The results indicate that upon biotinylation, the inherent mobility of the biotin-binding region and the protruding thumb, with which the biotin group interacts in the holo protein, are significantly reduced. (+info)Light-dependent changes in redox status of the plastidic acetyl-CoA carboxylase and its regulatory component. (2/158)
Plastidic acetyl-CoA carboxylase (ACCase; EC 6.4.1.2), which catalyses the synthesis of malonyl-CoA and is the regulatory enzyme of fatty acid synthesis, is activated by light, presumably under redox regulation. To obtain evidence of redox regulation in vivo, the activity of ACCase was examined in pea chloroplasts isolated from plants kept in darkness (dark-ACCase) or after exposure to light for 1 h (light-ACCase) in the presence or absence of a thiol-reducing agent, dithiothreitol (DTT). The protein level was similar for light-ACCase and dark-ACCase, but the activity of light-ACCase in the absence of DTT was approx. 3-fold that of dark-ACCase. The light-ACCase and dark-ACCase were activated approx. 2-fold and 6-fold by DTT respectively, indicating that light-ACCase was in a much more reduced, active form than the dark-ACCase. This is the first demonstration of the light-dependent reduction of ACCase in vivo. Measurement of the activities of ACCase, carboxyltransferase and biotin carboxylase in the presence and absence of DTT, and the thiol-oxidizing agent, 5, 5'-dithiobis-(2-nitrobenzoic) acid, revealed that the carboxyltransferase reaction, but not the biotin carboxylase reaction, was redox-regulated. The cysteine residue(s) responsible for redox regulation probably reside on the carboxyltransferase component. Measurement of the pH dependence of biotin carboxylase and carboxyltransferase activities in the ACCase suggested that both components affect the activity of ACCase in vivo at a physiological pH range. These results suggest that the activation of ACCase by light is caused partly by the pH-dependent activation of two components and by the reductive activation of carboxyltransferase. (+info)Sec-dependent pathway and DeltapH-dependent pathway do not share a common translocation pore in thylakoidal protein transport. (3/158)
Thylakoidal proteins of plant chloroplasts are transported to thylakoids via several different pathways, including the DeltapH-dependent and the Sec-dependent pathways. In this study, we asked if these two pathways utilize a common translocation pore. A fusion protein consisting of a 23-kDa subunit of the oxygen evolving complex and Escherichia coli biotin carboxyl carrier protein was biotinylated in E. coli cells and purified. When incubated with isolated pea thylakoids in the absence of avidin, the purified fusion protein was imported into the thylakoids via the DeltapH-dependent pathway. However in the presence of avidin, the fusion protein became lodged in the thylakoid membranes, with its N terminus reaching the thylakoidal lumen, while its C-terminal segment complexed with avidin exposed on the thylakoidal surface. The translocation intermediate of the fusion protein inhibited the import of authentic 23-kDa subunit, suggesting that it occupies a putative translocation pore for the DeltapH-dependent pathway. However the intermediate did not block import of the 33-kDa subunit of the oxygen evolving complex, which is a substrate for the Sec-dependent pathway. These results provide evidence against the possibility of a common translocation pore shared by the Sec-dependent pathway and the DeltapH-dependent pathway. (+info)Polyketide synthase acyl carrier protein (ACP) as a substrate and a catalyst for malonyl ACP biosynthesis. (4/158)
BACKGROUND: Using an acyl-acyl carrier protein (ACP) as a starter unit, type II polyketide synthases (PKSs) generate a wide range of polyketide products by successive decarboxylative condensations with the two-carbon donor malonyl (ACP). In vitro experiments have demonstrated that polyketide biosynthesis in reconstituted PKS systems requires the fatty acid synthase (FAS) enzyme malonyl CoA:ACP acyltransferase (FabD) from streptomycetes. It has also been shown that holo-ACPs from a type II PKS can catalyze self-malonylation in the presence of malonyl CoA and negate this FabD requirement. The relative roles of FabD and ACP self-malonylation in PKS biosynthesis in vivo are still not known. RESULTS: We have examined the ACP specificity of the Streptomyces glaucescens FabD and shown that it reacts specifically with monomeric forms of ACP, with comparable k(cat)/K(M) values for ACPs from both type II PKS and FAS systems. Incubations of tetracenomycin ACP (TcmM) with the Escherichia coli FAS ACP (AcpP) unexpectedly revealed that, in addition to the self-malonylation process, TcmM can catalyze the malonylation of AcpP. The k(cat)/K(M) value for the TcmM-catalyzed malonylation of S. glaucescens FAS ACP is two orders of magnitude smaller than that observed for the FabD-catalyzed process. CONCLUSIONS: The ability of a PKS ACP to catalyze malonylation of a FAS ACP is a surprising finding and demonstrates for the first time that PKS ACPs and FabD can catalyze the same reaction. The differences in the catalytic efficiency of these two proteins rationalizes in vitro observations that FabD-independent polyketide biosynthesis proceeds only at high concentrations of a PKS ACP. (+info)Kinetic analysis of the actinorhodin aromatic polyketide synthase. (5/158)
Type II polyketide synthases (PKSs) are bacterial multienzyme systems that catalyze the biosynthesis of a broad range of natural products. A core set of subunits, consisting of a ketosynthase, a chain length factor, an acyl carrier protein (ACP) and possibly a malonyl CoA:ACP transacylase (MAT) forms a "minimal" PKS. They generate a poly-beta-ketone backbone of a specified length from malonyl-CoA derived building blocks. Here we (a) report on the kinetic properties of the actinorhodin minimal PKS, and (b) present further data in support of the requirement of the MAT. Kinetic analysis showed that the apoACP is a competitive inhibitor of minimal PKS activity, demonstrating the importance of protein-protein interactions between the polypeptide moiety of the ACP and the remainder of the minimal PKS. In further support of the requirement of MAT for PKS activity, two new findings are presented. First, we observe hyperbolic dependence of PKS activity on MAT concentration, saturating at very low amounts (half-maximal rate at 19.7 +/- 5.1 nM). Since MAT can support PKS activity at less than 1/100 the typical concentration of the ACP and ketosynthase/chain length factor components, it is difficult to rule out the presence of trace quantities of MAT in a PKS reaction mixture. Second, an S97A mutant was constructed at the nucleophilic active site of the MAT. Not only can this mutant protein support PKS activity, it is also covalently labeled by [(14)C]malonyl-CoA, demonstrating that the serine nucleophile (which has been the target of PMSF inhibition in earlier studies) is dispensible for MAT activity in a Type II PKS system. (+info)Heterologous expression, purification, reconstitution and kinetic analysis of an extended type II polyketide synthase. (6/158)
BACKGROUND: Polyketide synthases (PKSs) are bacterial multienzyme systems that synthesize a broad range of natural products. The 'minimal' PKS consists of a ketosynthase, a chain length factor, an acyl carrier protein and a malonyl transferase. Auxiliary components (ketoreductases, aromatases and cyclases are involved in controlling the oxidation level and cyclization of the nascent polyketide chain. We describe the heterologous expression and reconstitution of several auxiliary PKS components including the actinorhodin ketoreductase (act KR), the griseusin aromatase/cyclase (gris ARO/CYC), and the tetracenomycin aromatase/cyclase (tcm ARO/CYC). RESULTS: The polyketide products of reconstituted act and tcm PKSs were identical to those identified in previous in vivo studies. Although stable protein-protein interactions were not detected between minimal and auxiliary PKS components, kinetic analysis revealed that the extended PKS comprised of the act minimal PKS, the act KR and the gris ARO/CYC had a higher turnover number than the act minimal PKS plus the act KR or the act minimal PKS alone. Adding the tcm ARO/CYC to the tcm minimal PKS also increased the overall rate. CONCLUSIONS: Until recently the principal strategy for functional analysis of PKS subunits was through heterologous expression of recombinant PKSs in Streptomyces. Our results corroborate the implicit assumption that the product isolated from whole-cell systems is the dominant product of the PKS. They also suggest that an intermediate is channeled between the various subunits, and pave the way for more detailed structural and mechanistic analysis of these multienzyme systems. (+info)Recombinant carboxyltransferase responsive to redox of pea plastidic acetyl-CoA carboxylase. (7/158)
Acetyl-CoA carboxylase regulates the rate of fatty acid synthesis. This enzyme in plants is localized in plastids and is believed to be composed of biotin carboxyl carrier protein, biotin carboxylase, and carboxyltransferase made up of alpha and beta polypeptides, although the enzyme has not been purified yet. Accumulated evidence shows that pea plastidic acetyl-CoA carboxylase is activated by light and the activation is caused by light-dependent reduction of carboxyltransferase, but not of biotin carboxylase, via a redox cascade. To understand the reductive activation of carboxyltransferase at the molecular level here, we obtained the active enzyme composed of decahistidine-tagged (His tag) alpha and beta polypeptides through the expression of the pea plastidic carboxyltransferase gene in Escherichia coli. Gel filtration showed that the molecular size of the recombinant carboxyltransferase is in agreement with that of partially purified carboxyltransferase from pea chloroplasts. The catalytic activity of the recombinant enzyme was similar to that of native carboxyltransferase. These results indicate that the molecular structure and conformation of recombinant carboxyltransferase resemble those of its native counterpart and that native carboxyltransferase is indeed composed of alpha and beta polypeptides. This recombinant enzyme was activated by dithiothreitol, a known reductant of S-S bonds, with a profile similar to that of its native counterpart. The recombinant enzyme was activated by reduced thioredoxin-f, a signal transducer of redox potential in chloroplasts under irradiation. Thus, this enzyme was redox-regulated, like that of the native carboxyltransferase. (+info)Identification of proteins of Escherichia coli and Saccharomyces cerevisiae that specifically bind to C/C mismatches in DNA. (8/158)
The pathways leading to G:C-->C:G transversions and their repair mechanisms remain uncertain. C/C and G/G mismatches arising during DNA replication are a potential source of G:C-->C:G transversions. The Escherichia coli mutHLS mismatch repair pathway efficiently corrects G/G mismatches, whereas C/C mismatches are a poor substrate. Escherichia coli must have a more specific repair pathway to correct C/C mismatches. In this study, we performed gel-shift assays to identify C/C mismatch-binding proteins in cell extracts of E. COLI: By testing heteroduplex DNA (34mers) containing C/C mismatches, two specific band shifts were generated in the gels. The band shifts were due to mismatch-specific binding of proteins present in the extracts. Cell extracts of a mutant strain defective in MutM protein did not produce a low-mobility complex. Purified MutM protein bound efficiently to the C/C mismatch-containing heteroduplex to produce the low-mobility complex. The second protein, which produced a high-mobility complex with the C/C mismatches, was purified to homogeneity, and the amino acid sequence revealed that this protein was the FabA protein of E.COLI: The high-mobility complex was not formed in cell extracts of a fabA mutant. From these results it is possible that MutM and FabA proteins are components of repair pathways for C/C mismatches in E.COLI: Furthermore, we found that Saccharomyces cerevisiae OGG1 protein, a functional homolog of E.COLI: MutM protein, could specifically bind to the C/C mismatches in DNA. (+info)Fatty acid synthase type II (FASN2) is an alternative form of fatty acid synthase, which is a multi-functional enzyme complex responsible for the de novo synthesis of palmitate, a 16-carbon saturated fatty acid. In contrast to the classical type I fatty acid synthase (FASN), which is found in the cytoplasm and exists as a homodimer, FASN2 is localized in the mitochondria and consists of individual, monofunctional enzymes that catalyze each step of the fatty acid synthesis process.
The type II fatty acid synthase system includes several enzymes: acetyl-CoA carboxylase (ACC), which provides malonyl-CoA; 3-ketoacyl-CoA thiolase, which catalyzes the initial condensation of acetyl-CoA and malonyl-CoA to form acetoacetyl-CoA; 3-hydroxyacyl-CoA dehydrogenase/enoyl-CoA hydratase (HAD), which catalyzes the reduction, dehydration, and isomerization of acetoacetyl-CoA to form hydroxybutyryl-CoA; 3-ketoacyl-CoA reductase, which reduces hydroxybutyryl-CoA to butyryl-CoA; and enoyl-CoA reductase (ECR), which catalyzes the final reduction of butyryl-CoA to palmitate.
FASN2 is involved in various cellular processes, including energy metabolism, lipid biosynthesis, and protein acetylation. Dysregulation of FASN2 has been implicated in several diseases, such as cancer, obesity, and neurodegenerative disorders.
Fatty acid synthases (FAS) are a group of enzymes that are responsible for the synthesis of fatty acids in the body. They catalyze a series of reactions that convert acetyl-CoA and malonyl-CoA into longer chain fatty acids, which are then used for various purposes such as energy storage or membrane formation.
The human genome encodes two types of FAS: type I and type II. Type I FAS is a large multifunctional enzyme complex found in the cytoplasm of cells, while type II FAS consists of individual enzymes located in the mitochondria. Both types of FAS play important roles in lipid metabolism, but their regulation and expression differ depending on the tissue and physiological conditions.
Inhibition of FAS has been explored as a potential therapeutic strategy for various diseases, including cancer, obesity, and metabolic disorders. However, more research is needed to fully understand the complex mechanisms regulating FAS activity and its role in human health and disease.
Fatty acids are carboxylic acids with a long aliphatic chain, which are important components of lipids and are widely distributed in living organisms. They can be classified based on the length of their carbon chain, saturation level (presence or absence of double bonds), and other structural features.
The two main types of fatty acids are:
1. Saturated fatty acids: These have no double bonds in their carbon chain and are typically solid at room temperature. Examples include palmitic acid (C16:0) and stearic acid (C18:0).
2. Unsaturated fatty acids: These contain one or more double bonds in their carbon chain and can be further classified into monounsaturated (one double bond) and polyunsaturated (two or more double bonds) fatty acids. Examples of unsaturated fatty acids include oleic acid (C18:1, monounsaturated), linoleic acid (C18:2, polyunsaturated), and alpha-linolenic acid (C18:3, polyunsaturated).
Fatty acids play crucial roles in various biological processes, such as energy storage, membrane structure, and cell signaling. Some essential fatty acids cannot be synthesized by the human body and must be obtained through dietary sources.
Fatty acid synthase (FAS) is a multi-enzyme complex that plays a crucial role in the synthesis of long-chain fatty acids in the body. There are two main types of FAS: type I and type II.
Type I fatty acid synthase, also known as FASN, is found primarily in the cytoplasm of cells in tissues such as the liver, adipose tissue, and lactating mammary glands. It is a large protein made up of several distinct enzymatic domains that work together to synthesize long-chain fatty acids from acetyl-CoA and malonyl-CoA.
The process of fatty acid synthesis involves a series of reactions, starting with the condensation of acetyl-CoA and malonyl-CoA to form acetoacetyl-CoA. This reaction is followed by a series of reductions, dehydrations, and another reduction to form a saturated fatty acid molecule with 16 carbons (palmitate).
Type I FAS is often upregulated in conditions associated with increased lipogenesis, such as obesity, metabolic syndrome, and certain types of cancer. Inhibiting FAS has been explored as a potential therapeutic strategy for treating these conditions.
Nitric Oxide Synthase Type II (NOS2), also known as Inducible Nitric Oxide Synthase (iNOS), is an enzyme that catalyzes the production of nitric oxide (NO) from L-arginine. Unlike other isoforms of NOS, NOS2 is not constitutively expressed and its expression can be induced by various stimuli such as cytokines, lipopolysaccharides, and bacterial products. Once induced, NOS2 produces large amounts of NO, which plays a crucial role in the immune response against invading pathogens. However, excessive or prolonged production of NO by NOS2 has been implicated in various pathological conditions such as inflammation, septic shock, and neurodegenerative disorders.
Nitric Oxide Synthase (NOS) is a group of enzymes that catalyze the production of nitric oxide (NO) from L-arginine. There are three distinct isoforms of NOS, each with different expression patterns and functions:
1. Neuronal Nitric Oxide Synthase (nNOS or NOS1): This isoform is primarily expressed in the nervous system and plays a role in neurotransmission, synaptic plasticity, and learning and memory processes.
2. Inducible Nitric Oxide Synthase (iNOS or NOS2): This isoform is induced by various stimuli such as cytokines, lipopolysaccharides, and hypoxia in a variety of cells including immune cells, endothelial cells, and smooth muscle cells. iNOS produces large amounts of NO, which functions as a potent effector molecule in the immune response, particularly in the defense against microbial pathogens.
3. Endothelial Nitric Oxide Synthase (eNOS or NOS3): This isoform is constitutively expressed in endothelial cells and produces low levels of NO that play a crucial role in maintaining vascular homeostasis by regulating vasodilation, inhibiting platelet aggregation, and preventing smooth muscle cell proliferation.
Overall, NOS plays an essential role in various physiological processes, including neurotransmission, immune response, cardiovascular function, and respiratory regulation. Dysregulation of NOS activity has been implicated in several pathological conditions such as hypertension, atherosclerosis, neurodegenerative diseases, and inflammatory disorders.
Cerulenin is a fungal metabolite that inhibits the enzyme delta-9-desaturase, which is involved in fatty acid synthesis. This compound is often used in research to study the biology and function of fatty acid synthase and lipid metabolism. It has been investigated for its potential as an anti-cancer agent, but its clinical use is not approved due to its limited specificity and potential toxicity.
Nitric oxide (NO) is a molecule made up of one nitrogen atom and one oxygen atom. In the body, it is a crucial signaling molecule involved in various physiological processes such as vasodilation, immune response, neurotransmission, and inhibition of platelet aggregation. It is produced naturally by the enzyme nitric oxide synthase (NOS) from the amino acid L-arginine. Inhaled nitric oxide is used medically to treat pulmonary hypertension in newborns and adults, as it helps to relax and widen blood vessels, improving oxygenation and blood flow.
Unsaturated fatty acids are a type of fatty acid that contain one or more double bonds in their carbon chain. These double bonds can be either cis or trans configurations, although the cis configuration is more common in nature. The presence of these double bonds makes unsaturated fatty acids more liquid at room temperature and less prone to spoilage than saturated fatty acids, which do not have any double bonds.
Unsaturated fatty acids can be further classified into two main categories: monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). MUFAs contain one double bond in their carbon chain, while PUFAs contain two or more.
Examples of unsaturated fatty acids include oleic acid (a MUFA found in olive oil), linoleic acid (a PUFA found in vegetable oils), and alpha-linolenic acid (an omega-3 PUFA found in flaxseed and fish). Unsaturated fatty acids are essential nutrients for the human body, as they play important roles in various physiological processes such as membrane structure, inflammation, and blood clotting. It is recommended to consume a balanced diet that includes both MUFAs and PUFAs to maintain good health.
Omega-3 fatty acids are a type of polyunsaturated fats that are essential for human health. The "omega-3" designation refers to the location of a double bond in the chemical structure of the fatty acid, specifically three carbon atoms from the end of the molecule.
There are three main types of omega-3 fatty acids: eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). EPA and DHA are primarily found in fatty fish, such as salmon, mackerel, and sardines, as well as in algae. ALA is found in plant sources, such as flaxseeds, chia seeds, walnuts, and some vegetable oils.
Omega-3 fatty acids have been shown to have numerous health benefits, including reducing inflammation, lowering the risk of heart disease, improving brain function, and supporting eye health. They are also important for fetal development during pregnancy and breastfeeding. It is recommended that adults consume at least 250-500 milligrams of combined EPA and DHA per day, although higher intakes may be beneficial for certain conditions. ALA can be converted to EPA and DHA in the body, but this process is not very efficient, so it is important to consume preformed EPA and DHA from dietary sources or supplements.
Nonesterified fatty acids (NEFA), also known as free fatty acids (FFA), refer to fatty acid molecules that are not bound to glycerol in the form of triglycerides or other esters. In the bloodstream, NEFAs are transported while bound to albumin and can serve as a source of energy for peripheral tissues. Under normal physiological conditions, NEFA levels are tightly regulated by the body; however, elevated NEFA levels have been associated with various metabolic disorders such as insulin resistance, obesity, and type 2 diabetes.
Fatty acid synthesis inhibitors are a class of drugs that block the production of fatty acids in the body. Fatty acids are necessary for the normal functioning of the body, but an overproduction of certain types of fatty acids can contribute to the development of various medical conditions, such as obesity, diabetes, and cardiovascular disease.
Fatty acid synthesis inhibitors work by targeting enzymes involved in the synthesis of fatty acids, particularly fatty acid synthase (FAS). FAS is an enzyme that plays a key role in the production of palmitate, a saturated fatty acid that is a building block for other fatty acids. By inhibiting FAS, these drugs can reduce the amount of palmitate and other fatty acids produced in the body.
There are several types of fatty acid synthesis inhibitors, including:
1. Orlistat (Xenical, Alli): This drug works by blocking the action of lipases, enzymes that break down dietary fats in the gut. By preventing the absorption of dietary fats, orlistat can help reduce calorie intake and promote weight loss.
2. Tebufelone: This is a non-steroidal anti-inflammatory drug (NSAID) that has been shown to inhibit FAS and reduce the production of pro-inflammatory cytokines. It has been studied as a potential treatment for various inflammatory conditions, such as rheumatoid arthritis and psoriasis.
3. Cerulenin: This is a natural product that inhibits FAS and has been used in research to study the role of fatty acid synthesis in various biological processes.
4. C75: This is a synthetic compound that inhibits FAS and has been studied as a potential anti-cancer agent, as cancer cells often have increased rates of fatty acid synthesis.
It's important to note that while fatty acid synthesis inhibitors can be effective in reducing the production of certain types of fatty acids, they may also have side effects and potential risks. Therefore, it is essential to use these drugs under the supervision of a healthcare provider and to follow their instructions carefully.
Sterol Regulatory Element Binding Protein 1 (SREBP-1) is a transcription factor that plays a crucial role in the regulation of lipid metabolism, primarily cholesterol and fatty acid biosynthesis. It binds to specific DNA sequences called sterol regulatory elements (SREs), which are present in the promoter regions of genes involved in lipid synthesis.
SREBP-1 exists in two isoforms, SREBP-1a and SREBP-1c, encoded by a single gene through alternative splicing. SREBP-1a is a stronger transcriptional activator than SREBP-1c and can activate both cholesterol and fatty acid synthesis genes. In contrast, SREBP-1c primarily regulates fatty acid synthesis genes.
Under normal conditions, SREBP-1 is found in the endoplasmic reticulum (ER) membrane as an inactive precursor bound to another protein called SREBP cleavage-activating protein (SCAP). When cells detect low levels of cholesterol or fatty acids, SCAP escorts SREBP-1 to the Golgi apparatus, where it undergoes proteolytic processing to release the active transcription factor. The active SREBP-1 then translocates to the nucleus and binds to SREs, promoting the expression of genes involved in lipid synthesis.
Overall, SREBP-1 is a critical regulator of lipid homeostasis, and its dysregulation has been implicated in various diseases, including obesity, insulin resistance, nonalcoholic fatty liver disease (NAFLD), and atherosclerosis.
Acyl Carrier Protein (ACP) is a small, acidic protein that plays a crucial role in the fatty acid synthesis process. It functions as a cofactor by carrying acyl groups during the elongation cycles of fatty acid chains. The ACP molecule has a characteristic prosthetic group known as 4'-phosphopantetheine, to which the acyl groups get attached covalently. This protein is highly conserved across different species and is essential for the production of fatty acids in both prokaryotic and eukaryotic organisms.