WorldWideScience

Sample records for acid binding protein

  1. Liver Fatty Acid Binding Protein and Obesity

    Atshaves, B.P.; Martin, G G; Hostetler, H.A.; McIntosh, A.L.; Kier, A B; Schroeder, F.

    2010-01-01

    While low levels of unesterified long chain fatty acids (LCFAs) are normal metabolic intermediates of dietary and endogenous fat, LCFAs are also potent regulators of key receptors/enzymes, and at high levels become toxic detergents within the cell. Elevated levels of LCFAs are associated with diabetes, obesity, and metabolic syndrome. Consequently, mammals evolved fatty acid binding proteins (FABPs) that bind/sequester these potentially toxic free fatty acids in the cytosol and present them f...

  2. Protein and ligand adaptation in a retinoic acid binding protein.

    Pattanayek, R.; Newcomer, M E

    1999-01-01

    A retinoic acid binding protein isolated from the lumen of the rat epididymis (ERABP) is a member of the lipocalin superfamily. ERABP binds both the all-trans and 9-cis isomers of retinoic acid, as well as the synthetic retinoid (E)-4-[2-(5,6,7,8)-tetrahydro-5,5,8,8-tetramethyl-2 napthalenyl-1 propenyl]-benzoic acid (TTNPB), a structural analog of all-trans retinoic acid. The structure of ERABP with a mixture of all-trans and 9-cis retinoic acid has previously been reported. To elucidate any ...

  3. Solution Structure and Backbone Dynamics of Human Liver Fatty Acid Binding Protein: Fatty Acid Binding Revisited

    Cai, Jun; Lücke, Christian; Chen, Zhongjing; Qiao, Ye; Klimtchuk, Elena; Hamilton, James A.

    2012-01-01

    Liver fatty acid binding protein (L-FABP), a cytosolic protein most abundant in liver, is associated with intracellular transport of fatty acids, nuclear signaling, and regulation of intracellular lipolysis. Among the members of the intracellular lipid binding protein family, L-FABP is of particular interest as it can i), bind two fatty acid molecules simultaneously and ii), accommodate a variety of bulkier physiological ligands such as bilirubin and fatty acyl CoA. To better understand the p...

  4. The clinical significance of fatty acid binding proteins

    Barbara Choromańska; Piotr Myśliwiec; Jacek Dadan; Hady Razak Hady; Adrian Chabowski

    2011-01-01

    Excessive levels of free fatty acids are toxic to cells. The human body has evolved a defense mechanism in the form of small cytoplasmic proteins called fatty acid binding proteins (FABPs) that bind long-chain fatty acids (LCFA), and then refer them to appropriate intracellular disposal sites (oxidation in mitochondria and peroxisomes or storage in the endoplasmic reticulum). So far, nine types of these proteins have been described, and their name refers to the place in which they were first ...

  5. Dissection of the Critical Binding Determinants of Cellular Retinoic Acid Binding Protein II by Mutagenesis and Fluorescence Binding Assay

    Vasileiou, Chrysoula; Lee, Kin Sing Stephen; Crist, Rachael M.; Vaezeslami, Soheila; Goins, Sarah M.; Geiger, James H.; Borhan, Babak

    2009-01-01

    The binding of retinoic acid to mutants of Cellular Retinoic Acid Binding Protein II (CRABPII) was evaluated to better understand the importance of the direct protein/ligand interactions. The important role of Arg111 for the correct structure and function of the protein was verified and other residues that directly affect retinoic acid binding have been identified. Furthermore, retinoic acid binding to CRABPII mutants that lack all previously identified interacting amino acids was rescued by ...

  6. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Gangi Setty, Thanuja [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Cho, Christine [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Govindappa, Sowmya [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Apicella, Michael A. [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Ramaswamy, S., E-mail: ramas@instem.res.in [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India)

    2014-07-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.

  7. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states

  8. Natural ligand binding and transfer from liver fatty acid binding protein (LFABP) to membranes.

    De Gerónimo, Eduardo; Hagan, Robert M; Wilton, David C; Córsico, Betina

    2010-09-01

    Liver fatty acid-binding protein (LFABP) is distinctive among fatty acid-binding proteins because it binds more than one molecule of long-chain fatty acid and a variety of diverse ligands. Also, the transfer of fluorescent fatty acid analogues to model membranes under physiological ionic strength follows a different mechanism compared to most of the members of this family of intracellular lipid binding proteins. Tryptophan insertion mutants sensitive to ligand binding have allowed us to directly measure the binding affinity, ligand partitioning and transfer to model membranes of natural ligands. Binding of fatty acids shows a cooperative mechanism, while acyl-CoAs binding presents a hyperbolic behavior. Saturated fatty acids seem to have a stronger partition to protein vs. membranes, compared to unsaturated fatty acids. Natural ligand transfer rates are more than 200-fold higher compared to fluorescently-labeled analogues. Interestingly, oleoyl-CoA presents a markedly different transfer behavior compared to the rest of the ligands tested, probably indicating the possibility of specific targeting of ligands to different metabolic fates. PMID:20541621

  9. Analysis of the ligand binding properties of recombinant bovine liver-type fatty acid binding protein

    Rolf, B; Oudenampsen-Krüger, E; Börchers, T;

    1995-01-01

    The coding part of the cDNA for bovine liver-type fatty acid binding protein (L-FABP) has been amplified by RT-PCR, cloned and used for the construction of an Escherichia coli (E. coli) expression system. The recombinant protein made up to 25% of the soluble E. coli proteins and could be isolated...... by a simple two step protocol combining ion exchange chromatography and gel filtration. Dissociation constants for binding of oleic acid, arachidonic acid, oleoyl-CoA, lysophosphatidic acid and the peroxisomal proliferator bezafibrate to L-FABP have been determined by titration calorimetry. All ligands were...... bound in a 2:1 stoichiometry, the dissociation constants for the first ligand bound were all in the micro molar range. Oleic acid was bound with the highest affinity and a Kd of 0.26 microM. Furthermore, binding of cholesterol to L-FABP was investigated with the Lipidex assay, a liposome binding assay...

  10. Interactions of human mannose-binding protein with lipoteichoic acids.

    Polotsky, V Y; Fischer, W; Ezekowitz, R A; Joiner, K A

    1996-01-01

    We explored the interaction of human recombinant mannose-binding protein and lipoteichoic acids (LTAs) by enzyme-linked immunosorbent assay. The best ligand was Micrococcus luteus lipomannan, followed by Enterococcus spp. LTA containing mono-, di-, and oligoglucosyl substituents. LTAs lacking terminal sugars (those of Streptococcus pyogenes and Staphylococcus aureus) or containing galactosyl substituents (those of Listeria spp. and Lactococcus spp.) were poor ligands. These results are consis...

  11. The clinical significance of fatty acid binding proteins

    Barbara Choromańska

    2011-11-01

    Full Text Available Excessive levels of free fatty acids are toxic to cells. The human body has evolved a defense mechanism in the form of small cytoplasmic proteins called fatty acid binding proteins (FABPs that bind long-chain fatty acids (LCFA, and then refer them to appropriate intracellular disposal sites (oxidation in mitochondria and peroxisomes or storage in the endoplasmic reticulum. So far, nine types of these proteins have been described, and their name refers to the place in which they were first identified or where they can be found in the greatest concentration. The most important FABPs were isolated from the liver (L-FABP, heart (H-FABP, intestine (I-FABP, brain (B-FABP, epidermis (E-FABP and adipocytes (A-FABP. Determination of H-FABP is used in the diagnosis of myocardial infarction, and L-FABP in kidney lesions of different etiologies. It is postulated that FABPs play an important role in the pathogenesis of metabolic diseases. Elevated levels of A-FABP have been found in the pericardial fat tissue and were associated with cardiac dysfunction in obese people. A rise in A-FABP has been observed in patients with type II diabetes. I-FABP is known as a marker of cell damage in the small intestine. Increased concentration of B-FABP has been associated with human brain tumors such as glioblastoma and astrocytoma, as well as with neurodegenerative diseases (Alzheimer’s, Parkinson’s and other disorders of cognitive function. The aim of this work was to present current data on the clinical significance of fatty acid binding proteins.

  12. Bile salt recognition by human liver fatty acid binding protein.

    Favretto, Filippo; Santambrogio, Carlo; D'Onofrio, Mariapina; Molinari, Henriette; Grandori, Rita; Assfalg, Michael

    2015-04-01

    Fatty acid binding proteins (FABPs) act as intracellular carriers of lipid molecules, and play a role in global metabolism regulation. Liver FABP (L-FABP) is prominent among FABPs for its wide ligand repertoire, which includes long-chain fatty acids as well as bile acids (BAs). In this work, we performed a detailed molecular- and atomic-level analysis of the interactions established by human L-FABP with nine BAs to understand the binding specificity for this important class of cholesterol-derived metabolites. Protein-ligand complex formation was monitored using heteronuclear NMR, steady-state fluorescence spectroscopy, and mass spectrometry. BAs were found to interact with L-FABP with dissociation constants in the narrow range of 0.6-7 μm; however, the diverse substitution patterns of the sterol nucleus and the presence of side-chain conjugation resulted in complexes endowed with various degrees of conformational heterogeneity. Trihydroxylated BAs formed monomeric complexes in which single ligand molecules occupied similar internal binding sites, based on chemical-shift perturbation data. Analysis of NMR line shapes upon progressive addition of taurocholate indicated that the binding mechanism departed from a simple binary association equilibrium, and instead involved intermediates along the binding path. The co-linear chemical shift behavior observed for L-FABP complexes with cholate derivatives added insight into conformational dynamics in the presence of ligands. The observed spectroscopic features of L-FABP/BA complexes, discussed in relation to ligand chemistry, suggest possible molecular determinants of recognition, with implications regarding intracellular BA transport. Our findings suggest that human L-FABP is a poorly selective, universal BA binder. PMID:25639618

  13. Cytosolic fatty acid-binding proteins: subjects and tools in metabolic research

    Fatty acid-binding proteins (FABPs) are major targets for specific binding of fatty acids in vivo. They constitute a widely expressed family of genetically related, small cytosolic proteins which very likely mediate intracellular transport of free long chain fatty acids. Genetic inhibition of FABP expression in vivo should therefore provide a useful tool to investigate and engineer fatty acid metabolism. (orig.)

  14. Buffer Interference with Protein Dynamics: A Case Study on Human Liver Fatty Acid Binding Protein

    Long, Dong; Yang, Daiwen

    2009-01-01

    Selection of suitable buffer types is often a crucial step for generating appropriate protein samples for NMR and x-ray crystallographic studies. Although the possible interaction between MES buffer (2-(N-morpholino)ethanesulfonic acid) and proteins has been discussed previously, the interaction is usually thought to have no significant effects on the structures of proteins. In this study, we demonstrate the direct, albeit weak, interaction between MES and human liver fatty acid binding prote...

  15. Sequence and structural features of binding site residues in protein-protein complexes: comparison with protein-nucleic acid complexes

    Selvaraj S

    2011-10-01

    Full Text Available Abstract Background Protein-protein interactions are important for several cellular processes. Understanding the mechanism of protein-protein recognition and predicting the binding sites in protein-protein complexes are long standing goals in molecular and computational biology. Methods We have developed an energy based approach for identifying the binding site residues in protein–protein complexes. The binding site residues have been analyzed with sequence and structure based parameters such as binding propensity, neighboring residues in the vicinity of binding sites, conservation score and conformational switching. Results We observed that the binding propensities of amino acid residues are specific for protein-protein complexes. Further, typical dipeptides and tripeptides showed high preference for binding, which is unique to protein-protein complexes. Most of the binding site residues are highly conserved among homologous sequences. Our analysis showed that 7% of residues changed their conformations upon protein-protein complex formation and it is 9.2% and 6.6% in the binding and non-binding sites, respectively. Specifically, the residues Glu, Lys, Leu and Ser changed their conformation from coil to helix/strand and from helix to coil/strand. Leu, Ser, Thr and Val prefer to change their conformation from strand to coil/helix. Conclusions The results obtained in this study will be helpful for understanding and predicting the binding sites in protein-protein complexes.

  16. Enterocyte Fatty Acid Binding Proteins (FABPs): Different Functions of Liver- and Intestinal- FABPs in the Intestine

    Gajda, Angela M.; Storch, Judith

    2014-01-01

    Fatty acid binding proteins (FABP) are highly abundant cytosolic proteins that are expressed in most mammalian tissues. In the intestinal enterocyte, both Liver- (LFABP; FABP1) and Intestinal-fatty acid binding proteins (IFABP; FABP2) are expressed. These proteins display high affinity binding for long chain fatty acids (FA) and other hydrophobic ligands, thus they are believed to be involved with uptake and trafficking of lipids in the intestine. In vitro studies have identified differences ...

  17. Local Unfolding of Fatty Acid Binding Protein to Allow Ligand Entry for Binding.

    Xiao, Tianshu; Fan, Jing-Song; Zhou, Hu; Lin, Qingsong; Yang, Daiwen

    2016-06-01

    Fatty acid binding proteins are responsible for the transportation of fatty acids in biology. Despite intensive studies, the molecular mechanism of fatty acid entry to and exit from the protein cavity is still unclear. Here a cap-closed variant of human intestinal fatty acid binding protein was generated by mutagenesis, in which the helical cap is locked to the β-barrel by a disulfide linkage. Structure determination shows that this variant adopts a closed conformation, but still uptakes fatty acids. Stopped-flow experiments indicate that a rate-limiting step exists before the ligand association and this step corresponds to the conversion of the closed form to the open one. NMR relaxation dispersion and H-D exchange data demonstrate the presence of two excited states: one is native-like, but the other adopts a locally unfolded structure. Local unfolding of helix 2 generates an opening for ligands to enter the protein cavity, and thus controls the ligand association rate. PMID:27105780

  18. Characterization of the comparative drug binding to intra- (liver fatty acid binding protein) and extra- (human serum albumin) cellular proteins.

    Rowland, Andrew; Hallifax, David; Nussio, Matthew R; Shapter, Joseph G; Mackenzie, Peter I; Brian Houston, J; Knights, Kathleen M; Miners, John O

    2015-01-01

    1. This study compared the extent, affinity, and kinetics of drug binding to human serum albumin (HSA) and liver fatty acid binding protein (LFABP) using ultrafiltration and surface plasmon resonance (SPR). 2. Binding of basic and neutral drugs to both HSA and LFABP was typically negligible. Binding of acidic drugs ranged from minor (fu > 0.8) to extensive (fu LFABP was observed for the acidic drugs torsemide and sulfinpyrazone, and for β-estradiol (a polar, neutral compound). 3. The extent of binding of acidic drugs to HSA was up to 40% greater than binding to LFABP. SPR experiments demonstrated comparable kinetics and affinity for the binding of representative acidic drugs (naproxen, sulfinpyrazone, and torsemide) to HSA and LFABP. 4. Simulations based on in vitro kinetic constants derived from SPR experiments and a rapid equilibrium model were undertaken to examine the impact of binding characteristics on compartmental drug distribution. Simulations provided mechanistic confirmation that equilibration of intracellular unbound drug with the extracellular unbound drug is attained rapidly in the absence of active transport mechanisms for drugs bound moderately or extensively to HSA and LFABP. PMID:25801059

  19. Fatty acid induced remodeling within the human liver fatty acid-binding protein.

    Sharma, Ashwani; Sharma, Amit

    2011-09-01

    We crystallized human liver fatty acid-binding protein (LFABP) in apo, holo, and intermediate states of palmitic acid engagement. Structural snapshots of fatty acid recognition, entry, and docking within LFABP support a heads-in mechanism for ligand entry. Apo-LFABP undergoes structural remodeling, where the first palmitate ingress creates the atomic environment for placement of the second palmitate. These new mechanistic insights will facilitate development of pharmacological agents against LFABP. PMID:21757748

  20. Fatty Acid Induced Remodeling within the Human Liver Fatty Acid-binding Protein*

    Sharma, Ashwani; Sharma, Amit

    2011-01-01

    We crystallized human liver fatty acid-binding protein (LFABP) in apo, holo, and intermediate states of palmitic acid engagement. Structural snapshots of fatty acid recognition, entry, and docking within LFABP support a heads-in mechanism for ligand entry. Apo-LFABP undergoes structural remodeling, where the first palmitate ingress creates the atomic environment for placement of the second palmitate. These new mechanistic insights will facilitate development of pharmacological agents against ...

  1. The liver fatty acid binding protein--comparison of cavity properties of intracellular lipid-binding proteins.

    Thompson, J; Ory, J; Reese-Wagoner, A; Banaszak, L

    1999-02-01

    The crystal and solution structures of all of the intracellular lipid binding proteins (iLBPs) reveal a common beta-barrel framework with only small local perturbations. All existing evidence points to the binding cavity and a poorly delimited 'portal' region as defining the function of each family member. The importance of local structure within the cavity appears to be its influence on binding affinity and specificity for the lipid. The portal region appears to be involved in the regulation of ligand exchange. Within the iLBP family, liver fatty acid binding protein or LFABP, has the unique property of binding two fatty acids within its internalized binding cavity rather than the commonly observed stoichiometry of one. Furthermore, LFABP will bind hydrophobic molecules larger than the ligands which will associate with other iLBPs. The crystal structure of LFABP contains two bound oleate molecules and provides the explanation for its unusual stoichiometry. One of the bound fatty acids is completely internalized and has its carboxylate interacting with an arginine and two serines. The second oleate represents an entirely new binding mode with the carboxylate on the surface of LFABP. The two oleates also interact with each other. Because of this interaction and its inner location, it appears the first oleate must be present before the second more external molecule is bound. PMID:10331654

  2. Fatty Acid- and Retinoid-binding Proteins Have Distinct Binding Pockets for the Two Types of Cargo*

    Jordanova, Rositsa; Groves, Matthew R.; Kostova, Elena; Woltersdorf, Christian; Liebau, Eva; Tucker, Paul A.

    2009-01-01

    Parasitic nematodes cause serious diseases in humans, animals, and plants. They have limited lipid metabolism and are reliant on lipid-binding proteins to acquire these metabolites from their hosts. Several structurally novel families of lipid-binding proteins in nematodes have been described, including the fatty acid- and retinoid-binding protein family (FAR). In Caenorhabditis elegans, used as a model for studying parasitic nematodes, eight C. elegans FAR proteins have been described. The c...

  3. Interaction of perfluoroalkyl acids with human liver fatty acid-binding protein.

    Sheng, Nan; Li, Juan; Liu, Hui; Zhang, Aiqian; Dai, Jiayin

    2016-01-01

    Perfluoroalkyl acids (PFAAs) are highly persistent and bioaccumulative, resulting in their broad distribution in humans and the environment. The liver is an important target for PFAAs, but the mechanisms behind PFAAs interaction with hepatocyte proteins remain poorly understood. We characterized the binding of PFAAs to human liver fatty acid-binding protein (hL-FABP) and identified critical structural features in their interaction. The binding interaction of PFAAs with hL-FABP was determined by fluorescence displacement and isothermal titration calorimetry (ITC) assay. Molecular simulation was conducted to define interactions at the binding sites. ITC measurement revealed that PFOA/PFNA displayed a moderate affinity for hL-FABP at a 1:1 molar ratio, a weak binding affinity for PFHxS and no binding for PFHxA. Moreover, the interaction was mainly mediated by electrostatic attraction and hydrogen bonding. Substitution of Asn111 with Asp caused loss of binding affinity to PFAA, indicating its crucial role for the initial PFAA binding to the outer binding site. Substitution of Arg122 with Gly caused only one molecule of PFAA to bind to hL-FABP. Molecular simulation showed that substitution of Arg122 increased the volume of the outer binding pocket, making it impossible to form intensive hydrophobic stacking and hydrogen bonds with PFOA, and highlighting its crucial role in the binding process. The binding affinity of PFAAs increased significantly with their carbon number. Arg122 and Asn111 played a pivotal role in these interactions. Our findings may help understand the distribution pattern, bioaccumulation, elimination, and toxicity of PFAAs in humans. PMID:25370009

  4. Structural and binding properties of two paralogous fatty acid binding proteins of Taenia solium metacestode.

    Seon-Hee Kim

    Full Text Available BACKGROUND: Fatty acid (FA binding proteins (FABPs of helminths are implicated in acquisition and utilization of host-derived hydrophobic substances, as well as in signaling and cellular interactions. We previously demonstrated that secretory hydrophobic ligand binding proteins (HLBPs of Taenia solium metacestode (TsM, a causative agent of neurocysticercosis (NC, shuttle FAs in the surrounding host tissues and inwardly transport the FAs across the parasite syncytial membrane. However, the protein molecules responsible for the intracellular trafficking and assimilation of FAs have remained elusive. METHODOLOGY/PRINCIPAL FINDINGS: We isolated two novel TsMFABP genes (TsMFABP1 and TsMFABP2, which encoded 133- and 136-amino acid polypeptides with predicted molecular masses of 14.3 and 14.8 kDa, respectively. They shared 45% sequence identity with each other and 15-95% with other related-members. Homology modeling demonstrated a characteristic β-barrel composed of 10 anti-parallel β-strands and two α-helices. TsMFABP2 harbored two additional loops between β-strands two and three, and β-strands six and seven, respectively. TsMFABP1 was secreted into cyst fluid and surrounding environments, whereas TsMFABP2 was intracellularly confined. Partially purified native proteins migrated to 15 kDa with different isoelectric points of 9.2 (TsMFABP1 and 8.4 (TsMFABP2. Both native and recombinant proteins bound to 11-([5-dimethylaminonaphthalene-1-sulfonyl]aminoundecannoic acid, dansyl-DL-α-amino-caprylic acid, cis-parinaric acid and retinol, which were competitively inhibited by oleic acid. TsMFABP1 exhibited high affinity toward FA analogs. TsMFABPs showed weak binding activity to retinol, but TsMFABP2 showed relatively high affinity. Isolation of two distinct genes from an individual genome strongly suggested their paralogous nature. Abundant expression of TsMFABP1 and TsMFABP2 in the canal region of worm matched well with the histological distributions

  5. Liver fatty acid-binding protein binds monoacylglycerol in vitro and in mouse liver cytosol.

    Lagakos, William S; Guan, Xudong; Ho, Shiu-Ying; Sawicki, Luciana Rodriguez; Corsico, Betina; Kodukula, Sarala; Murota, Kaeko; Stark, Ruth E; Storch, Judith

    2013-07-01

    Liver fatty acid-binding protein (LFABP; FABP1) is expressed both in liver and intestinal mucosa. Mice null for LFABP were recently shown to have altered metabolism of not only fatty acids but also monoacylglycerol, the two major products of dietary triacylglycerol hydrolysis (Lagakos, W. S., Gajda, A. M., Agellon, L., Binas, B., Choi, V., Mandap, B., Russnak, T., Zhou, Y. X., and Storch, J. (2011) Am. J. Physiol. Gastrointest. Liver Physiol. 300, G803-G814). Nevertheless, the binding and transport of monoacylglycerol (MG) by LFABP are uncertain, with conflicting reports in the literature as to whether this single chain amphiphile is in fact bound by LFABP. In the present studies, gel filtration chromatography of liver cytosol from LFABP(-/-) mice shows the absence of the low molecular weight peak of radiolabeled monoolein present in the fractions that contain LFABP in cytosol from wild type mice, indicating that LFABP binds sn-2 MG in vivo. Furthermore, solution-state NMR spectroscopy demonstrates two molecules of sn-2 monoolein bound in the LFABP binding pocket in positions similar to those found for oleate binding. Equilibrium binding affinities are ∼2-fold lower for MG compared with fatty acid. Finally, kinetic studies examining the transfer of a fluorescent MG analog show that the rate of transfer of MG is 7-fold faster from LFABP to phospholipid membranes than from membranes to membranes and occurs by an aqueous diffusion mechanism. These results provide strong support for monoacylglycerol as a physiological ligand for LFABP and further suggest that LFABP functions in the efficient intracellular transport of MG. PMID:23658011

  6. Liver Fatty Acid-binding Protein Binds Monoacylglycerol in Vitro and in Mouse Liver Cytosol*

    Lagakos, William S.; Guan, Xudong; Ho, Shiu-Ying; Sawicki, Luciana Rodriguez; Corsico, Betina; Kodukula, Sarala; Murota, Kaeko; Stark, Ruth E.; Storch, Judith

    2013-01-01

    Liver fatty acid-binding protein (LFABP; FABP1) is expressed both in liver and intestinal mucosa. Mice null for LFABP were recently shown to have altered metabolism of not only fatty acids but also monoacylglycerol, the two major products of dietary triacylglycerol hydrolysis (Lagakos, W. S., Gajda, A. M., Agellon, L., Binas, B., Choi, V., Mandap, B., Russnak, T., Zhou, Y. X., and Storch, J. (2011) Am. J. Physiol. Gastrointest. Liver Physiol. 300, G803–G814). Nevertheless, the binding and transport of monoacylglycerol (MG) by LFABP are uncertain, with conflicting reports in the literature as to whether this single chain amphiphile is in fact bound by LFABP. In the present studies, gel filtration chromatography of liver cytosol from LFABP−/− mice shows the absence of the low molecular weight peak of radiolabeled monoolein present in the fractions that contain LFABP in cytosol from wild type mice, indicating that LFABP binds sn-2 MG in vivo. Furthermore, solution-state NMR spectroscopy demonstrates two molecules of sn-2 monoolein bound in the LFABP binding pocket in positions similar to those found for oleate binding. Equilibrium binding affinities are ∼2-fold lower for MG compared with fatty acid. Finally, kinetic studies examining the transfer of a fluorescent MG analog show that the rate of transfer of MG is 7-fold faster from LFABP to phospholipid membranes than from membranes to membranes and occurs by an aqueous diffusion mechanism. These results provide strong support for monoacylglycerol as a physiological ligand for LFABP and further suggest that LFABP functions in the efficient intracellular transport of MG. PMID:23658011

  7. In Vitro Binding Capacity of Bile Acids by Defatted Corn Protein Hydrolysate

    Pierre Claver Irakoze

    2011-02-01

    Full Text Available Defatted corn protein was digested using five different proteases, Alcalase, Trypsin, Neutrase, Protamex and Flavourzyme, in order to produce bile acid binding peptides. Bile acid binding capacity was analyzed in vitro using peptides from different proteases of defatted corn hydrolysate. Some crystalline bile acids like sodium glycocholate, sodium cholate and sodium deoxycholate were individually tested using HPLC to see which enzymes can release more peptides with high bile acid binding capacity. Peptides from Flavourzyme defatted corn hydrolysate exhibited significantly (p

  8. Cholesterol-lowering effect of rice bran protein containing bile acid-binding proteins.

    Wang, Jilite; Shimada, Masaya; Kato, Yukina; Kusada, Mio; Nagaoka, Satoshi

    2015-01-01

    Dietary plant protein is well known to reduce serum cholesterol levels. Rice bran is a by-product of rice milling and is a good source of protein. The present study examined whether feeding rats a high-cholesterol diet containing 10% rice bran protein (RBP) for 10 d affected cholesterol metabolism. Rats fed dietary RBP had lower serum total cholesterol levels and increased excretion of fecal steroids, such as cholesterol and bile acids, than those fed dietary casein. In vitro assays showed that RBP strongly bound to taurocholate, and inhibited the micellar solubility of cholesterol, compared with casein. Moreover, the bile acid-binding proteins of the RBP were eluted by a chromatographic column conjugated with cholic acid, and one of them was identified as hypothetical protein OsJ_13801 (NCBI accession No. EAZ29742) using MALDI-TOF mass spectrometry analysis. These results suggest that the hypocholesterolemic action of the RBP may be caused by the bile acid-binding proteins. PMID:25374002

  9. Expression of liver fatty acid binding protein in hepatocellular carcinoma.

    Cho, Soo-Jin; Ferrell, Linda D; Gill, Ryan M

    2016-04-01

    Loss of expression of liver fatty acid binding protein (LFABP) by immunohistochemistry has been shown to be characteristic of a subset of hepatocellular adenomas (HCAs) in which HNF1A is inactivated. Transformation to hepatocellular carcinoma is thought to be a very rare phenomenon in the HNF1A-inactivated variant of HCA. However, we recently observed 2 cases at our institution, 1 definite hepatocellular carcinoma and 1 possible hepatocellular carcinoma, with loss of LFABP staining, raising the possibility that LFABP down-regulation may be associated with hepatocellular carcinogenesis. Our aim was to evaluate hepatocellular carcinomas arising in various backgrounds and with varying degrees of differentiation for loss of LFABP staining. Twenty total cases of hepatocellular carcinoma were examined. Thirteen cases arose in a background of cirrhosis due to hepatitis C (n = 8) or steatohepatitis (n = 5); 7 cases arose in a noncirrhotic background, with 2 cases arising within HNF1A-inactivated variant HCA and 2 cases arising within inflammatory variant HCA. Complete loss of expression of LFABP was seen in 6 of 20 cases, including 2 cases of hepatocellular carcinoma arising within HNF1A-inactivated variant HCA. Thus, loss of staining for LFABP appears to be common in hepatocellular carcinoma and may be seen in well-differentiated hepatocellular carcinoma. Therefore, LFABP loss should not be interpreted as evidence for hepatocellular adenoma over carcinoma, when other features support a diagnosis of hepatocellular carcinoma. The findings raise consideration for a role of HNF1A inactivation in hepatocellular carcinogenesis, particularly in less differentiated tumors. PMID:26997447

  10. Direct Channeling of Retinoic Acid between Cellular Retinoic Acid-Binding Protein II and Retinoic Acid Receptor Sensitizes Mammary Carcinoma Cells to Retinoic Acid-Induced Growth Arrest

    Budhu, Anuradha S.; Noy, Noa

    2002-01-01

    Cellular retinoic acid-binding protein II (CRABP-II) is an intracellular lipid-binding protein that associates with retinoic acid with a subnanomolar affinity. We previously showed that CRABP-II enhances the transcriptional activity of the nuclear receptor with which it shares a common ligand, namely, the retinoic acid receptor (RAR), and we suggested that it may act by delivering retinoic acid to this receptor. Here, the mechanisms underlying the effects of CRABP-II on the transcriptional ac...

  11. A fatty-acid-binding protein from wheat kernels

    Castagnaro, Atilio; García Olmedo, Francisco

    1994-01-01

    A protein of about 7 kDa (W-FABP) has been isolated from mature wheat kernels by H2O extraction and gel filtration of the extract, followed by two steps of high-performance liquid chromatography. The N-terminal amino acid sequence has been determined up to the 28th residue and found to be identical (except for positions 4 and 5) to that deduced from a barley cDNA (EMBL X15257), which had been improperly classified as a non-specific lipid transfer protein (LTP2). Similarly with LTPs, W-FABP do...

  12. The human fatty acid-binding protein family: Evolutionary divergences and functions

    Smathers Rebecca L

    2011-03-01

    Full Text Available Abstract Fatty acid-binding proteins (FABPs are members of the intracellular lipid-binding protein (iLBP family and are involved in reversibly binding intracellular hydrophobic ligands and trafficking them throughout cellular compartments, including the peroxisomes, mitochondria, endoplasmic reticulum and nucleus. FABPs are small, structurally conserved cytosolic proteins consisting of a water-filled, interior-binding pocket surrounded by ten anti-parallel beta sheets, forming a beta barrel. At the superior surface, two alpha-helices cap the pocket and are thought to regulate binding. FABPs have broad specificity, including the ability to bind long-chain (C16-C20 fatty acids, eicosanoids, bile salts and peroxisome proliferators. FABPs demonstrate strong evolutionary conservation and are present in a spectrum of species including Drosophila melanogaster, Caenorhabditis elegans, mouse and human. The human genome consists of nine putatively functional protein-coding FABP genes. The most recently identified family member, FABP12, has been less studied.

  13. Enterocyte Fatty Acid Binding Proteins (FABPs): Different Functions of Liver- and Intestinal- FABPs in the Intestine

    Gajda, Angela M.; Storch, Judith

    2014-01-01

    SUMMARY Fatty acid binding proteins (FABP) are highly abundant cytosolic proteins that are expressed in most mammalian tissues. In the intestinal enterocyte, both Liver- (LFABP; FABP1) and Intestinal-fatty acid binding proteins (IFABP; FABP2) are expressed. These proteins display high affinity binding for long chain fatty acids (FA) and other hydrophobic ligands, thus they are believed to be involved with uptake and trafficking of lipids in the intestine. In vitro studies have identified differences in ligand binding stoichiometry and specificity, and in mechanisms of FA transfer to membranes, and it has been hypothesized that LFABP and IFABP have difference functions in the enterocyte. Studies directly comparing LFABP- and IFABP-null mice have revealed markedly different phenotypes, indicating that these proteins indeed have different functions in intestinal lipid metabolism and whole body energy homeostasis. In this review, we discuss the evolving knowledge of the functions of LFABP and IFABP in the intestinal enterocyte. PMID:25458898

  14. Molecular mechanism of recombinant liver fatty acid binding protein's antioxidant activity

    Yan, Jing; Gong, Yuewen; She, Yi-Min; Wang, Guqi; Roberts, Michael S; Burczynski, Frank J.

    2009-01-01

    Hepatocytes expressing liver fatty acid binding protein (L-FABP) are known to be more resistant to oxidative stress than those devoid of this protein. The mechanism for the observed antioxidant activity is not known. We examined the antioxidant mechanism of a recombinant rat L-FABP in the presence of a hydrophilic (AAPH) or lipophilic (AMVN) free radical generator. Recombinant L-FABP amino acid sequence and its amino acid oxidative products following oxidation were identified by MALDI quadrup...

  15. The primary structure of fatty-acid-binding protein from nurse shark liver. Structural and evolutionary relationship to the mammalian fatty-acid-binding protein family.

    Medzihradszky, K F; Gibson, B W; Kaur, S; Yu, Z H; Medzihradszky, D; Burlingame, A L; Bass, N M

    1992-02-01

    The primary structure of a fatty-acid-binding protein (FABP) isolated from the liver of the nurse shark (Ginglymostoma cirratum) was determined by high-performance tandem mass spectrometry (employing multichannel array detection) and Edman degradation. Shark liver FABP consists of 132 amino acids with an acetylated N-terminal valine. The chemical molecular mass of the intact protein determined by electrospray ionization mass spectrometry (Mr = 15124 +/- 2.5) was in good agreement with that calculated from the amino acid sequence (Mr = 15121.3). The amino acid sequence of shark liver FABP displays significantly greater similarity to the FABP expressed in mammalian heart, peripheral nerve myelin and adipose tissue (61-53% sequence similarity) than to the FABP expressed in mammalian liver (22% similarity). Phylogenetic trees derived from the comparison of the shark liver FABP amino acid sequence with the members of the mammalian fatty-acid/retinoid-binding protein gene family indicate the initial divergence of an ancestral gene into two major subfamilies: one comprising the genes for mammalian liver FABP and gastrotropin, the other comprising the genes for mammalian cellular retinol-binding proteins I and II, cellular retinoic-acid-binding protein myelin P2 protein, adipocyte FABP, heart FABP and shark liver FABP, the latter having diverged from the ancestral gene that ultimately gave rise to the present day mammalian heart-FABP, adipocyte FABP and myelin P2 protein sequences. The sequence for intestinal FABP from the rat could be assigned to either subfamily, depending on the approach used for phylogenetic tree construction, but clearly diverged at a relatively early evolutionary time point. Indeed, sequences proximately ancestral or closely related to mammalian intestinal FABP, liver FABP, gastrotropin and the retinoid-binding group of proteins appear to have arisen prior to the divergence of shark liver FABP and should therefore also be present in elasmobranchs

  16. Sialic Acid Binding Properties of Soluble Coronavirus Spike (S1 Proteins: Differences between Infectious Bronchitis Virus and Transmissible Gastroenteritis Virus

    Christine Winter

    2013-07-01

    Full Text Available The spike proteins of a number of coronaviruses are able to bind to sialic acids present on the cell surface. The importance of this sialic acid binding ability during infection is, however, quite different. We compared the spike protein of transmissible gastroenteritis virus (TGEV and the spike protein of infectious bronchitis virus (IBV. Whereas sialic acid is the only receptor determinant known so far for IBV, TGEV requires interaction with its receptor aminopeptidase N to initiate infection of cells. Binding tests with soluble spike proteins carrying an IgG Fc-tag revealed pronounced differences between these two viral proteins. Binding of the IBV spike protein to host cells was in all experiments sialic acid dependent, whereas the soluble TGEV spike showed binding to APN but had no detectable sialic acid binding activity. Our results underline the different ways in which binding to sialoglycoconjugates is mediated by coronavirus spike proteins.

  17. A continuous displacement immunoassay for human heart-type fatty acid-binding protein in plasma

    van der Voort, D; Pelsers, MMAL; Korf, J; Hermens, WT; Glatz, JFC

    2004-01-01

    Human heart-type fatty acid-binding protein (FABP) is suggested as an early plasma marker of acute myocardial infarction (AMI), and several studies have proved that, for early diagnosis of AMI, FABP performs better than myoglobin, which is a more often used early marker protein. Because serial measu

  18. Urinary excretion of fatty acid-binding proteins in idiopathic membranous nephropathy.

    Hofstra, J.M.; Deegens, J.K.J.; Steenbergen, E.J.; Wetzels, J.F.M.

    2008-01-01

    BACKGROUND: It is suggested that proteinuria contributes to progressive renal failure by inducing tubular cell injury. The site of injury is unknown. Most studies have used markers of proximal tubular cell damage. Fatty acid-binding proteins (FABPs) are intracellular carrier proteins with different

  19. Heart-type fatty-acid-binding protein (FABP3) is a lysophosphatidic acid-binding protein in human coronary artery endothelial cells

    Tsukahara, Ryoko; Haniu, Hisao; Matsuda, Yoshikazu; Tsukahara, Tamotsu

    2014-01-01

    Fatty-acid-binding protein 3, muscle and heart (FABP3), also known as heart-type FABP, is a member of the family of intracellular lipid-binding proteins. It is a small cytoplasmic protein with a molecular mass of about 15 kDa. FABPs are known to be carrier proteins for transporting fatty acids and other lipophilic substances from the cytoplasm to the nucleus, where these lipids are released to a group of nuclear receptors such as peroxisome proliferator-activated receptors (PPARs). In this study, using lysophosphatidic acid (LPA)-coated agarose beads, we have identified FABP3 as an LPA carrier protein in human coronary artery endothelial cells (HCAECs). Administration of LPA to HCAECs resulted in a dose-dependent increase in PPARγ activation. Furthermore, the LPA-induced PPARγ activation was abolished when the FABP3 expression was reduced using small interfering RNA (siRNA). We further show that the nuclear fraction of control HCAECs contained a significant amount of exogenously added LPA, whereas FABP3 siRNA-transfected HCAECs had a decreased level of LPA in the nucleus. Taken together, these results suggest that FABP3 governs the transcriptional activities of LPA by targeting them to cognate PPARγ in the nucleus. PMID:25426414

  20. Heart-type fatty-acid-binding protein (FABP3 is a lysophosphatidic acid-binding protein in human coronary artery endothelial cells

    Ryoko Tsukahara

    2014-01-01

    Full Text Available Fatty-acid-binding protein 3, muscle and heart (FABP3, also known as heart-type FABP, is a member of the family of intracellular lipid-binding proteins. It is a small cytoplasmic protein with a molecular mass of about 15 kDa. FABPs are known to be carrier proteins for transporting fatty acids and other lipophilic substances from the cytoplasm to the nucleus, where these lipids are released to a group of nuclear receptors such as peroxisome proliferator-activated receptors (PPARs. In this study, using lysophosphatidic acid (LPA-coated agarose beads, we have identified FABP3 as an LPA carrier protein in human coronary artery endothelial cells (HCAECs. Administration of LPA to HCAECs resulted in a dose-dependent increase in PPARγ activation. Furthermore, the LPA-induced PPARγ activation was abolished when the FABP3 expression was reduced using small interfering RNA (siRNA. We further show that the nuclear fraction of control HCAECs contained a significant amount of exogenously added LPA, whereas FABP3 siRNA-transfected HCAECs had a decreased level of LPA in the nucleus. Taken together, these results suggest that FABP3 governs the transcriptional activities of LPA by targeting them to cognate PPARγ in the nucleus.

  1. Possible involvement of lipoic acid in binding protein-dependent transport systems in Escherichia coli.

    Richarme, G

    1985-01-01

    We describe the properties of the binding protein dependent-transport of ribose, galactose, and maltose and of the lactose permease, and the phosphoenolpyruvate-glucose phosphotransferase transport systems in a strain of Escherichia coli which is deficient in the synthesis of lipoic acid, a cofactor involved in alpha-keto acid dehydrogenation. Such a strain can grow in the absence of lipoic acid in minimal medium supplemented with acetate and succinate. Although the lactose permease and the p...

  2. Towards an understanding of Mesocestoides vogae fatty acid binding proteins' roles.

    Gabriela Alvite

    Full Text Available Two fatty acid binding proteins, MvFABPa and MvFABPb were identified in the parasite Mesocestoides vogae (Platyhelmithes, Cestoda. Fatty acid binding proteins are small intracellular proteins whose members exhibit great diversity. Proteins of this family have been identified in many organisms, of which Platyhelminthes are among the most primitive. These proteins have particular relevance in flatworms since de novo synthesis of fatty acids is absent. Fatty acids should be captured from the media needing an efficient transport system to uptake and distribute these molecules. While HLBPs could be involved in the shuttle of fatty acids to the surrounding host tissues and convey them into the parasite, FABPs could be responsible for the intracellular trafficking. In an effort to understand the role of MvFABPs in fatty acid transport of M. vogae larvae, we analysed the intracellular localization of both MvFABPs and the co-localization with in vivo uptake of fatty acid analogue BODIPY FL C16. Immunohistochemical studies on larvae sections using specific antibodies, showed a diffuse cytoplasmic distribution of each protein with some expression in nuclei and mitochondria. MvFABPs distribution was confirmed by mass spectrometry identification from 2D-electrophoresis of larvae subcellular fractions. This work is the first report showing intracellular distribution of MvFABPs as well as the co-localization of these proteins with the BODIPY FL C16 incorporated from the media. Our results suggest that fatty acid binding proteins could target fatty acids to cellular compartments including nuclei. In this sense, M. vogae FABPs could participate in several cellular processes fulfilling most of the functions attributed to vertebrate's counterparts.

  3. Sequence and structural features of binding site residues in protein-protein complexes: comparison with protein-nucleic acid complexes

    Selvaraj S; Jayaram B; Saranya N; Gromiha M; Fukui Kazuhiko

    2011-01-01

    Abstract Background Protein-protein interactions are important for several cellular processes. Understanding the mechanism of protein-protein recognition and predicting the binding sites in protein-protein complexes are long standing goals in molecular and computational biology. Methods We have developed an energy based approach for identifying the binding site residues in protein–protein complexes. The binding site residues have been analyzed with sequence and structure based parameters such...

  4. Early Diagnosis of Intestinal Ischemia Using Urinary and Plasma Fatty Acid Binding Proteins

    Thuijls, Geertje; van Wijck, Kim; Grootjans, Joep; Derikx, Joep P. M.; van Bijnen, Annemarie A.; Heineman, Erik; Dejong, Cornelis H. C.; Buurman, Wim A.; Poeze, Martijn

    2011-01-01

    Objective: This study aims at improving diagnosis of intestinal ischemia, by measuring plasma and urinary fatty acid binding protein (FABP) levels. Methods: Fifty consecutive patients suspected of intestinal ischemia were included and blood and urine were sampled at time of suspicion. Plasma and uri

  5. Cytosolic fatty acid-binding proteins: subjects and tools in metabolic research

    Binas, B. [Max Delbrueck Center for Molecular Medicine, Berlin-Buch (Germany)

    1998-12-31

    Fatty acid-binding proteins (FABPs) are major targets for specific binding of fatty acids in vivo. They constitute a widely expressed family of genetically related, small cytosolic proteins which very likely mediate intracellular transport of free long chain fatty acids. Genetic inhibition of FABP expression in vivo should therefore provide a useful tool to investigate and engineer fatty acid metabolism. (orig.) [Deutsch] Fettsaeurebindungsproteine (FABPs) sind wichtige Bindungsstellen fuer Fettsaeuren in vivo; sie bilden eine breit exprimierte Familie genetisch verwandter kleiner Zytosoleiweisse, die sehr wahrscheinlich den intrazellulaeren Transport unveresterter langkettiger Fettsaeuren vermitteln. Die genetische Hemmung der FABP-Expanssion in vivo bietet sich deshalb als Werkzeug zur Erforschung und gezielten Veraenderung des Fettsaeurestoffwechsels an. (orig.)

  6. Hepatic phenotype of liver fatty acid binding protein gene-ablated mice

    Martin, Gregory G.; Atshaves, Barbara P.; Huang, Huan; McIntosh, Avery L.; Williams, Brad J.; Pai, Pei-Jing; Russell, David H.; Kier, Ann B.; Schroeder, Friedhelm

    2009-01-01

    Although the function of liver fatty acid binding protein in hepatic fatty acid metabolism has been extensively studied, its potential role in hepatic cholesterol homeostasis is less clear. Although hepatic cholesterol accumulation was initially reported in L-FABP-null female mice, that study was performed with early N2 backcross generation mice. To resolve whether the hepatic cholesterol phenotype in these L-FABP−/− mice was attributable to genetic inhomogeneity, these L-FABP−/− mice were fu...

  7. Glucose regulates fatty acid binding protein interaction with lipids and peroxisome proliferator-activated receptor α

    Hostetler, Heather A.; Balanarasimha, Madhumitha; Huang, Huan; Kelzer, Matthew S.; Kaliappan, Alagammai; Kier, Ann B.; Schroeder, Friedhelm

    2010-01-01

    Although the pathophysiology of diabetes is characterized by elevated levels of glucose and long-chain fatty acids (LCFA), nuclear mechanisms linking glucose and LCFA metabolism are poorly understood. As the liver fatty acid binding protein (L-FABP) shuttles LCFA to the nucleus, where L-FABP directly interacts with peroxisome proliferator-activated receptor-α (PPARα), the effect of glucose on these processes was examined. In vitro studies showed that L-FABP strongly bound glucose and glucose-...

  8. Interactions between Human Liver Fatty Acid Binding Protein and Peroxisome Proliferator Activated Receptor Selective Drugs

    Tony Velkov

    2013-01-01

    Fatty acid binding proteins (FABPs) act as intracellular shuttles for fatty acids as well as lipophilic xenobiotics to the nucleus, where these ligands are released to a group of nuclear receptors called the peroxisome proliferator activated receptors (PPARs). PPAR mediated gene activation is ultimately involved in maintenance of cellular homeostasis through the transcriptional regulation of metabolic enzymes and transporters that target the activating ligand. Here we show that liver- (L-) FA...

  9. Relationship between serum adiopocyte fatty acid binding protein and atherosclerosis in chronic kidney disease

    吴晶

    2014-01-01

    Objective To investigate the expression of serum adiopocyte fatty acid binding protein(A-FABP)in chronic kidney disease(CKD)and the role that A-FABP plays in CKD with atherosclerosis.Methods A total of 138 patients with CKD and 20 health control volunteers(HC)were involved in this study.The levels of serum AFABP,free fatty acid(FFA),interleukin-6(IL-6),

  10. DNA binding protein identification by combining pseudo amino acid composition and profile-based protein representation

    Liu, Bin; Wang, Shanyi; Wang, Xiaolong

    2015-10-01

    DNA-binding proteins play an important role in most cellular processes. Therefore, it is necessary to develop an efficient predictor for identifying DNA-binding proteins only based on the sequence information of proteins. The bottleneck for constructing a useful predictor is to find suitable features capturing the characteristics of DNA binding proteins. We applied PseAAC to DNA binding protein identification, and PseAAC was further improved by incorporating the evolutionary information by using profile-based protein representation. Finally, Combined with Support Vector Machines (SVMs), a predictor called iDNAPro-PseAAC was proposed. Experimental results on an updated benchmark dataset showed that iDNAPro-PseAAC outperformed some state-of-the-art approaches, and it can achieve stable performance on an independent dataset. By using an ensemble learning approach to incorporate more negative samples (non-DNA binding proteins) in the training process, the performance of iDNAPro-PseAAC was further improved. The web server of iDNAPro-PseAAC is available at http://bioinformatics.hitsz.edu.cn/iDNAPro-PseAAC/.

  11. Bile acid binding capacity of fish protein hydrolysates from discard species of the West Mediterranean Sea.

    Pérez-Gálvez, Raúl; García-Moreno, Pedro J; Morales-Medina, Rocío; Guadix, Antonio; Guadix, Emilia M

    2015-04-01

    Fish protein hydrolysates (FPH), produced from the six main discard species from the West Mediterranean Sea (sardine, horse mackerel, axillary seabream, bogue, small-spotted catshark and blue whiting) were tested for their bile acid binding capacity. This capacity is directly linked to the ability to inhibit bile reabsorption in the ileum and therefore to lower cholesterol levels in the bloodstream. From each species, FPH were obtained by three different enzymatic treatments employing two serine endoproteases (subtilisin and trypsin) sequentially or in combination. The results show statistically significant differences among the fish species, attaining interesting average values of bile acid binding capacity for blue whiting (27.32% relative to cholestyramine on an equal protein basis) and horse mackerel (27.42% relative to cholestyramine on an equal protein basis). The enzymatic treatments did not significantly affect the ability of a given species to bind bile acids. These results are similar to other protein sources, such as soy protein or casein, of proven hypocholesterolemic effect. It can be concluded that fish protein hydrolysates from these discard species are suitable as ingredients in the formulation of cholesterol-lowering supplements. PMID:25756593

  12. Competitive Binding to Cuprous Ions of Protein and BCA in the Bicinchoninic Acid Protein Assay

    Huang, Tao; Long, Mian; Huo, Bo

    2010-01-01

    Although Bicinchoninic acid (BCA) has been widely used to determine protein concentration, the mechanism of interaction between protein, copper ion and BCA in this assay is still not well known. Using the Micro BCA protein assay kit (Pierce Company), we measured the absorbance at 562 nm of BSA solutions with different concentrations of protein, and also varied the BCA concentration. When the concentration of protein was increased, the absorbance exhibited the known linear and nonlinear increa...

  13. Biochemical Roles for Conserved Residues in the Bacterial Fatty Acid-binding Protein Family.

    Broussard, Tyler C; Miller, Darcie J; Jackson, Pamela; Nourse, Amanda; White, Stephen W; Rock, Charles O

    2016-03-18

    Fatty acid kinase (Fak) is a ubiquitous Gram-positive bacterial enzyme consisting of an ATP-binding protein (FakA) that phosphorylates the fatty acid bound to FakB. In Staphylococcus aureus, Fak is a global regulator of virulence factor transcription and is essential for the activation of exogenous fatty acids for incorporation into phospholipids. The 1.2-Å x-ray structure of S. aureus FakB2, activity assays, solution studies, site-directed mutagenesis, and in vivo complementation were used to define the functions of the five conserved residues that define the FakB protein family (Pfam02645). The fatty acid tail is buried within the protein, and the exposed carboxyl group is bound by a Ser-93-fatty acid carboxyl-Thr-61-His-266 hydrogen bond network. The guanidinium of the invariant Arg-170 is positioned to potentially interact with a bound acylphosphate. The reduced thermal denaturation temperatures of the T61A, S93A, and H266A FakB2 mutants illustrate the importance of the hydrogen bond network in protein stability. The FakB2 T61A, S93A, and H266A mutants are 1000-fold less active in the Fak assay, and the R170A mutant is completely inactive. All FakB2 mutants form FakA(FakB2)2 complexes except FakB2(R202A), which is deficient in FakA binding. Allelic replacement shows that strains expressing FakB2 mutants are defective in fatty acid incorporation into phospholipids and virulence gene transcription. These conserved residues are likely to perform the same critical functions in all bacterial fatty acid-binding proteins. PMID:26774272

  14. Fatty Acid Binding Proteins FABP9 and FABP10 Participate in Antibacterial Responses in Chinese Mitten Crab, Eriocheir sinensis

    Lin Cheng; Xing-Kun Jin; Wei-Wei Li; Shuang Li; Xiao-Nv Guo; Juan Wang; Ya-Nan Gong; Lin He; Qun Wang

    2013-01-01

    Invertebrates rely solely on the innate immune system for defense against pathogens and other stimuli. Fatty acid binding proteins (FABP), members of the lipid binding proteins superfamily, play a crucial role in fatty acid transport and lipid metabolism and are also involved in gene expression induced by fatty acids. In the vertebrate immune system, FABP is involved in inflammation regulated by fatty acids through its interaction with peroxidase proliferator activate receptors (PPARs). Howev...

  15. From keys to bulldozers: expanding roles for winged helix domains in nucleic-acid-binding proteins.

    Harami, Gábor M; Gyimesi, Máté; Kovács, Mihály

    2013-07-01

    The winged helix domain (WHD) is a widespread nucleic-acid-binding protein structural element found in all kingdoms of life. Although the overall structure of the WHD is conserved, its functional properties and interaction profiles are extremely versatile. WHD-containing proteins can exploit nearly the full spectrum of nucleic acid structural features for recognition and even covalent modification or noncovalent rearrangement of target molecules. WHD functions range from sequence-recognizing keys in transcription factors and bulldozer-like strand-separating wedges in helicases to mediators of protein-protein interactions (PPIs). Further investigations are needed to understand the contribution of WHD structural dynamics to nucleic-acid-modifying enzymatic functions. PMID:23768997

  16. Urinary Excretion of Fatty Acid-Binding Protein Reflects Stress Overload on the Proximal Tubules

    Kamijo, Atsuko; Sugaya, Takeshi; Hikawa, Akihisa; Okada, Mitsuhiro; Okumura, Fumikazu; Yamanouchi, Masaya; Honda, Akiko; Okabe, Masaru; Fujino, Tomoya; Hirata, Yasunobu; Omata, Masao; Kaneko, Ritsuko; Fujii, Hiroshi; Fukamizu, Akiyoshi; Kimura, Kenjiro

    2004-01-01

    Urinary excretion of human liver-type fatty acid-binding protein (hL-FABP), which is expressed in human proximal tubules and engaged in free fatty acid (FFA) metabolism, was reported to reflect the clinical prognosis of chronic kidney disease. Here we have investigated the pathophysiological significance of hL-FABP in a model of protein overload nephropathy. Because L-FABP is not expressed in the wild-type mice, we generated hL-FABP chromosomal gene transgenic (Tg) mice. Tg mice were intraper...

  17. Interactions between Human Liver Fatty Acid Binding Protein and Peroxisome Proliferator Activated Receptor Selective Drugs

    Tony Velkov

    2013-01-01

    Full Text Available Fatty acid binding proteins (FABPs act as intracellular shuttles for fatty acids as well as lipophilic xenobiotics to the nucleus, where these ligands are released to a group of nuclear receptors called the peroxisome proliferator activated receptors (PPARs. PPAR mediated gene activation is ultimately involved in maintenance of cellular homeostasis through the transcriptional regulation of metabolic enzymes and transporters that target the activating ligand. Here we show that liver- (L- FABP displays a high binding affinity for PPAR subtype selective drugs. NMR chemical shift perturbation mapping and proteolytic protection experiments show that the binding of the PPAR subtype selective drugs produces conformational changes that stabilize the portal region of L-FABP. NMR chemical shift perturbation studies also revealed that L-FABP can form a complex with the PPAR ligand binding domain (LBD of PPARα. This protein-protein interaction may represent a mechanism for facilitating the activation of PPAR transcriptional activity via the direct channeling of ligands between the binding pocket of L-FABP and the PPARαLBD. The role of L-FABP in the delivery of ligands directly to PPARα via this channeling mechanism has important implications for regulatory pathways that mediate xenobiotic responses and host protection in tissues such as the small intestine and the liver where L-FABP is highly expressed.

  18. Binding of 14C-5-aminolevulinic acid to a stromal protein from developing pea chloroplasts

    14-5-Aminolevulinic acid (14C-ALA) binds to a stromal protein with an apparent molecular weight of 42-43 KD on LDS and non-denaturing gels. The reaction is rapid. Binding is inhibited by sulfhydryl reagents, mM concentrations of levulinic, dihydroxy heptanoic acids and gabaculine, 10 μM N-methylprotoporphyrin. Dicarboxilic acids, such as δKG, Glu, OAA, do not inhibit. Chloramphenicol, ATP, protoporphyrin, anoxia, light, darkness have no effect. The product, once formed, is stable to treatment with 5% conc. HCl in cold acetone. It can be chased in a second incubation with unlabeled ALA, but not with levulinic acid. No activity was detected in the subplastidic membrane fractions. Western blot analysis failed to reveal any homology between the labeled protein and either cytochrome for ALA dehydratase. This ALA-binding protein was not formed in chloroplasts isolated from fully expanded pea leaves. Therefore, it is deemed likely to participate in ALA metabolism during chloroplast development

  19. Liver-type fatty acid binding protein interacts with hepatocyte nuclear factor 4α

    McIntosh, Avery L.; Petrescu, Anca D.; Heather A. Hostetler; Kier, Ann B.; Schroeder, Friedhelm

    2013-01-01

    Hepatocyte nuclear factor 4α (HNF4α) regulates liver type fatty acid binding protein (L-FABP) gene expression. Conversely as shown herein, L-FABP structurally and functionally also interacts with HNF4α. Fluorescence resonance energy transfer (FRET) between Cy3-HNF4α (donor) and Cy5-L-FABP (acceptor) as well as FRET microscopy detected L-FABP in close proximity (~80 Å) to HNF4α, binding with high affinity Kd ~250–300 nM. Circular dichroism (CD) determined that the HNF4α/L-FABP interaction alte...

  20. Fatty Acid Binding Protein 4 Deficiency Protects against Oxygen-Induced Retinopathy in Mice

    Magali Saint-Geniez; Elisa Ghelfi; Xiaoliang Liang; Chenwei Yu; Carrie Spencer; Stephanie Abend; Gokhan Hotamisligil; Sule Cataltepe

    2014-01-01

    Retinopathy of prematurity (ROP) is a leading cause of blindness in children worldwide due to increasing survival rates of premature infants. Initial suppression, followed by increased production of the retinal vascular endothelial growth factor-A (VEGF) expression are key events that trigger the pathological neovascularization in ROP. Fatty acid binding protein 4 (FABP4) is an intracellular lipid chaperone that is induced by VEGF in a subset of endothelial cells. FABP4 exhibits a pro-angioge...

  1. Fatty acid binding protein deletion suppresses inflammatory pain through endocannabinoid/N-acylethanolamine-dependent mechanisms

    Kaczocha, Martin; Glaser, Sherrye T.; Maher, Thomas; Clavin, Brendan; Hamilton, John; O’Rourke, Joseph; Rebecchi, Mario; Puopolo, Michelino; Owada, Yuji; Thanos, Panayotis K.

    2015-01-01

    Background Fatty acid binding proteins (FABPs) serve as intracellular carriers that deliver endocannabinoids and N-acylethanolamines to their catabolic enzymes. Inhibition of FABPs reduces endocannabinoid transport and catabolism in cells and FABP inhibitors produce antinociceptive and anti-inflammatory effects in mice. Potential analgesic effects in mice lacking FABPs, however, have not been tested. Findings Mice lacking FABP5 and FABP7, which exhibit highest affinities for endocannabinoids,...

  2. Anti-peptide aptamers recognize amino acid sequence and bind a protein epitope.

    Xu, W; Ellington, A. D.

    1996-01-01

    In vitro selection of nucleic acid binding species (aptamers) is superficially similar to the immune response. Both processes produce biopolymers that can recognize targets with high affinity and specificity. While antibodies are known to recognize the sequence and conformation of protein surface features (epitopes), very little is known about the precise interactions between aptamers and their epitopes. Therefore, aptamers that could recognize a particular epitope, a peptide fragment of huma...

  3. Fatty-Acid Binding Proteins Modulate Sleep and Enhance Long-Term Memory Consolidation in Drosophila

    Gerstner, Jason R.; Vanderheyden, William M.; Shaw, Paul J.; Landry, Charles F.; Yin, Jerry C. P.

    2011-01-01

    Sleep is thought to be important for memory consolidation, since sleep deprivation has been shown to interfere with memory processing. However, the effects of augmenting sleep on memory formation are not well known, and testing the role of sleep in memory enhancement has been limited to pharmacological and behavioral approaches. Here we test the effect of overexpressing the brain-type fatty acid binding protein (Fabp7) on sleep and long-term memory (LTM) formation in Drosophila melanogaster. ...

  4. Urinary liver-type fatty acid-binding protein change in gestational diabetes mellitus.

    Fu, Wen-Jin; Wang, Du-Juan; Deng, Ren-Tang; Huang, Zhi-Hong; Chen, Mei-Lian; Jang, You-Ming; Wen, Shu; Yang, Hong-Ling; Huang, Xian-zhang

    2015-09-01

    We compared urinary liver-type fatty acid-binding protein (L-FABP) among non-pregnant and pregnant women with and without gestational diabetes mellitus (GDM). Higher urinary L-FABP was found in pregnant with and without GDM, and considerably higher urinary L-FABP was found in the GDM group compared with the non-GDM group. Hyperglycemia and anemia were related with high urinary L-FABP expression. PMID:26254248

  5. Nucleomorphin. A novel, acidic, nuclear calmodulin-binding protein from dictyostelium that regulates nuclear number.

    Myre, Michael A; O'Day, Danton H

    2002-05-31

    Probing of Dictyostelium discoideum cell extracts after SDS-PAGE using (35)S-recombinant calmodulin (CaM) as a probe has revealed approximately three-dozen Ca(2+)-dependent calmodulin binding proteins. Here, we report the molecular cloning, expression, and subcellular localization of a gene encoding a novel calmodulin-binding protein (CaMBP); we have called nucleomorphin, from D. discoideum. A lambdaZAP cDNA expression library of cells from multicellular development was screened using a recombinant calmodulin probe ((35)S-VU1-CaM). The open reading frame of 1119 nucleotides encodes a polypeptide of 340 amino acids with a calculated molecular mass of 38.7 kDa and is constitutively expressed throughout the Dictyostelium life cycle. Nucleomorphin contains a highly acidic glutamic/aspartic acid inverted repeat (DEED) with significant similarity to the conserved nucleoplasmin domain and a putative transmembrane domain in the carboxyl-terminal region. Southern blotting reveals that nucleomorphin exists as a single copy gene. Using gel overlay assays and CaM-agarose we show that bacterially expressed nucleomorphin binds to bovine CaM in a Ca(2+)-dependent manner. Amino-terminal fusion to the green fluorescence protein (GFP) showed that GFP-NumA localized to the nucleus as distinct arc-like patterns similar to heterochromatin regions. GFP-NumA lacking the acidic DEED repeat still showed arc-like accumulations at the nuclear periphery, but the number of nuclei in these cells was increased markedly compared with control cells. Cells expressing GFP-NumA lacking the transmembrane domain localized to the nuclear periphery but did not affect nuclear number or gross morphology. Nucleomorphin is the first nuclear CaMBP to be identified in Dictyostelium. Furthermore, these data present the first identification of a member of the nucleoplasmin family as a calmodulin-binding protein and suggest nucleomorphin has a role in nuclear structure in Dictyostelium. PMID:11919178

  6. Urinary liver-type fatty acid-binding protein predicts adverse outcomes in acute kidney injury

    Ferguson, Michael A.; Vaidya, Vishal S.; Waikar, Sushrut S.; Collings, Fitz B.; Sunderland, Kelsey E.; Gioules, Costas J.; Bonventre, Joseph V.

    2009-01-01

    Acute kidney injury (AKI) is a common condition with significant associated morbidity and mortality. The insensitivity and non-specificity of traditional markers of renal dysfunction prevent timely diagnosis, estimation of the severity of renal injury, and the administration of possible therapeutic agents. Here, we determine the prognostic ability of urinary liver-type fatty acid-binding protein (L-FABP), and further characterize its sensitivity and specificity as a biomarker of AKI. Initial ...

  7. The Role of Urinary Liver-Type Fatty Acid-Binding Protein in Critically Ill Patients

    Cho, Eunjung; Yang, Ha Na; Jo, Sang-Kyung; Cho, Won-Yong; Kim, Hyoung-Kyu

    2013-01-01

    Although several urinary biomarkers have been validated as early diagnostic markers of acute kidney injury (AKI), their usefulness as outcome predictors is not well established. This study aimed to determine the diagnostic and prognostic abilities of urinary liver-type fatty acid-binding protein (L-FABP) in heterogeneous critically ill patients. We prospectively collected data on patients admitted to medical and surgical intensive care units (ICUs) from July 2010 to June 2011. Urine neutrophi...

  8. Urinary L-Type Fatty Acid-Binding Protein Can Reflect Renal Tubulointerstitial Injury

    Tanaka, Tamami; DOI, Kent; Maeda-Mamiya, Rui; Negishi, Kousuke; Portilla, Didier; Sugaya, Takeshi; Fujita, Toshiro; Noiri, Eisei

    2009-01-01

    This study aimed to elucidate the role of L-type fatty acid-binding protein (L-FABP) in renal tubulointerstitial injury using a mouse adenine-induced renal injury model. C57BL/6 mice fed excess dietary adenine for 6 weeks showed a gradual increase in levels of blood urea nitrogen (BUN). They also showed severe tubulointerstitial pathological findings, such as fibrosis and macrophage infiltration without glomerular damage, which were attenuated by treatment with either allopurinol or Y-700, a ...

  9. Solution structure of human intestinal fatty acid binding protein: Implications for ligand entry and exit

    Zhang Fengli [Boston University School of Medicine, Department of Biophysics (United States); Luecke, Christian [Johann Wolfgang Goethe-Universitaet (Germany); Baier, Leslie J. [NIDDK, NIH, Phoenix Epidemiology and Clinical Research Branch (United States); Sacchettini, James C. [Texas A and M University, Department of Biochemistry and Biophysics (United States); Hamilton, James A. [Boston University School of Medicine, Department of Biophysics (United States)

    1997-04-15

    The human intestinal fatty acid binding protein (I-FABP) is a small (131 amino acids) protein which binds dietary long-chain fatty acids in the cytosol of enterocytes. Recently, an alanine to threonine substitution at position 54 in I-FABP has been identified which affects fatty acid binding and transport, and is associated with the development of insulin resistance in several populations including Mexican-Americans and Pima Indians. To investigate the molecular basis of the binding properties of I-FABP, the 3D solution structure of the more common form of human I-FABP (Ala54) was studied by multidimensional NMR spectroscopy.Recombinant I-FABP was expressed from E. coli in the presence and absence of 15N-enriched media. The sequential assignments for non-delipidated I-FABP were completed by using 2D homonuclear spectra (COSY, TOCSY and NOESY) and 3D heteronuclear spectra(NOESY-HMQC and TOCSY-HMQC). The tertiary structure of human I-FABP was calculated by using the distance geometry program DIANA based on 2519 distance constraints obtained from the NMR data. Subsequent energy minimization was carried out by using the program SYBYL in the presence of distance constraints. The conformation of human I-FABP consists of 10 antiparallel {beta}-strands which form two nearly orthogonal {beta}-sheets of five strands each, and two short {alpha}-helices that connect the {beta}-strands A and B. The interior of the protein consists of a water-filled cavity between the two {beta}-sheets. The NMR solution structure of human I-FABP is similar to the crystal structure of rat I-FABP.The NMR results show significant conformational variability of certain backbone segments around the postulated portal region for the entry and exit of fatty acid ligand.

  10. Predicting DNA-binding sites of proteins from amino acid sequence

    Wu Feihong

    2006-05-01

    Full Text Available Abstract Background Understanding the molecular details of protein-DNA interactions is critical for deciphering the mechanisms of gene regulation. We present a machine learning approach for the identification of amino acid residues involved in protein-DNA interactions. Results We start with a Naïve Bayes classifier trained to predict whether a given amino acid residue is a DNA-binding residue based on its identity and the identities of its sequence neighbors. The input to the classifier consists of the identities of the target residue and 4 sequence neighbors on each side of the target residue. The classifier is trained and evaluated (using leave-one-out cross-validation on a non-redundant set of 171 proteins. Our results indicate the feasibility of identifying interface residues based on local sequence information. The classifier achieves 71% overall accuracy with a correlation coefficient of 0.24, 35% specificity and 53% sensitivity in identifying interface residues as evaluated by leave-one-out cross-validation. We show that the performance of the classifier is improved by using sequence entropy of the target residue (the entropy of the corresponding column in multiple alignment obtained by aligning the target sequence with its sequence homologs as additional input. The classifier achieves 78% overall accuracy with a correlation coefficient of 0.28, 44% specificity and 41% sensitivity in identifying interface residues. Examination of the predictions in the context of 3-dimensional structures of proteins demonstrates the effectiveness of this method in identifying DNA-binding sites from sequence information. In 33% (56 out of 171 of the proteins, the classifier identifies the interaction sites by correctly recognizing at least half of the interface residues. In 87% (149 out of 171 of the proteins, the classifier correctly identifies at least 20% of the interface residues. This suggests the possibility of using such classifiers to identify

  11. Molecular dynamics simulation of ligand dissociation from liver fatty acid binding protein.

    Dong Long

    Full Text Available The mechanisms of how ligands enter and leave the binding cavity of fatty acid binding proteins (FABPs have been a puzzling question over decades. Liver fatty acid binding protein (LFABP is a unique family member which accommodates two molecules of fatty acids in its cavity and exhibits the capability of interacting with a variety of ligands with different chemical structures and properties. Investigating the ligand dissociation processes of LFABP is thus a quite interesting topic, which however is rather difficult for both experimental approaches and ordinary simulation strategies. In the current study, random expulsion molecular dynamics simulation, which accelerates ligand motions for rapid dissociation, was used to explore the potential egress routes of ligands from LFABP. The results showed that the previously hypothesized "portal region" could be readily used for the dissociation of ligands at both the low affinity site and the high affinity site. Besides, one alternative portal was shown to be highly favorable for ligand egress from the high affinity site and be related to the unique structural feature of LFABP. This result lends strong support to the hypothesis from the previous NMR exchange studies, which in turn indicates an important role for this alternative portal. Another less favored potential portal located near the N-terminal end was also identified. Identification of the dissociation pathways will allow further mechanistic understanding of fatty acid uptake and release by computational and/or experimental techniques.

  12. Molecular dynamics simulation of ligand dissociation from liver fatty acid binding protein.

    Long, Dong; Mu, Yuguang; Yang, Daiwen

    2009-01-01

    The mechanisms of how ligands enter and leave the binding cavity of fatty acid binding proteins (FABPs) have been a puzzling question over decades. Liver fatty acid binding protein (LFABP) is a unique family member which accommodates two molecules of fatty acids in its cavity and exhibits the capability of interacting with a variety of ligands with different chemical structures and properties. Investigating the ligand dissociation processes of LFABP is thus a quite interesting topic, which however is rather difficult for both experimental approaches and ordinary simulation strategies. In the current study, random expulsion molecular dynamics simulation, which accelerates ligand motions for rapid dissociation, was used to explore the potential egress routes of ligands from LFABP. The results showed that the previously hypothesized "portal region" could be readily used for the dissociation of ligands at both the low affinity site and the high affinity site. Besides, one alternative portal was shown to be highly favorable for ligand egress from the high affinity site and be related to the unique structural feature of LFABP. This result lends strong support to the hypothesis from the previous NMR exchange studies, which in turn indicates an important role for this alternative portal. Another less favored potential portal located near the N-terminal end was also identified. Identification of the dissociation pathways will allow further mechanistic understanding of fatty acid uptake and release by computational and/or experimental techniques. PMID:19564911

  13. Liver Fatty Acid Binding Protein Gene Ablation Enhances Age-Dependent Weight Gain in Male Mice

    Martin, Gregory G.; Atshaves, Barbara P.; McIntosh, Avery L.; Payne, H. Ross; Mackie, John T.; Kier, Ann B.; Schroeder, Friedhelm

    2008-01-01

    Although studies performed in vitro and with transfected cells in culture suggest a role for liver fatty acid binding protein (L-FABP) in regulating fatty acid oxidation and fat deposition, the physiological significance of this possibility is not completely clear. To begin to address this question, the effect of L-FABP gene ablation on phenotype of standard rodent chow-fed male mice was examined with increasing age up to 18 mo. While young (2-3 mo) L-FABP null mice displayed no visually obvi...

  14. Liver-Type Fatty Acid-Binding Protein Attenuates Renal Injury Induced by Unilateral Ureteral Obstruction

    Kamijo-Ikemori, Atsuko; Sugaya, Takeshi; Obama, Ayako; Hiroi, Junya; Miura, Hiroshi; WATANABE, Minoru; Kumai, Toshio; Ohtani-Kaneko, Ritsuko; Hirata, Kazuaki; Kimura, Kenjiro

    2006-01-01

    Liver-type fatty-acid-binding protein (L-FABP), which has high affinity for long-chain fatty acid oxidation products, may be an effective endogenous antioxidant. To examine the role of L-FABP in tubulointerstitial damage, we used a unilateral ureteral obstruction (UUO) model. We established human L-FABP (hL-FABP) gene transgenic (Tg) mice and compared the tubulointerstitial pathology of the Tg mice (n = 23) with that of the wild-type (WT) mice (n = 23). Mice were sacrificed on days 2, 4, 5, o...

  15. Urinary Excretion of Liver Type Fatty Acid Binding Protein Accurately Reflects the Degree of Tubulointerstitial Damage

    Yokoyama, Takeshi; Kamijo-Ikemori, Atsuko; Sugaya, Takeshi; Hoshino, Seiko; Yasuda, Takashi; Kimura, Kenjiro

    2009-01-01

    To investigate the relationship between liver-type fatty acid-binding protein (L-FABP), a biomarker of chronic kidney disease, in the kidney and the degree of tubulointerstitial damage, folic acid (FA)-induced nephropathy was studied in a mouse model system. As renal L-FABP is not expressed in wild-type mice, human L-FABP (hL-FABP) transgenic mice were used in this study. hL-FABP is expressed in the renal proximal tubules of the transgenic mice that were injected intraperitoneally with FA in ...

  16. Visualization of Iron-Binding Micelles in Acidic Recombinant Biomineralization Protein, MamC

    Kashyap, Sanjay [Ames Laboratory; Woehl, Taylor [Ames Laboratory; Valverde-Tercedor, Carmen [University of Granada; Sanchez-Quesada, Miguel [University of Granada; Lopez, Concepcion Jimenez [University of Granada; Prozorov, Tanya [Ames Laboratory

    2014-03-07

    Biological macromolecules are utilized in low-temperature synthetic methods to exert precise control over nanoparticle nucleation and placement. They enable low-temperature formation of a variety of functional nanostructured materials with properties often not achieved via conventional synthetic techniques. Here we report on the in situ visualization of a novel acidic bacterial recombinant protein, MamC, commonly present in the magnetosome membrane of several magnetotactic bacteria, including Magnetococcus marinus, strain MC-1. Our findings provide an insight into the self-assembly of MamC and point to formation of the extended protein surface, which is assumed to play an important role in the formation of biotemplated inorganic nanoparticles. The self-organization of MamC is compared to the behavior of another acidic recombinant iron-binding protein, Mms6.

  17. Liver fatty acid binding protein: species variation and the accommodation of different ligands.

    Thompson, J; Reese-Wagoner, A; Banaszak, L

    1999-11-23

    The crystal structure of rat liver fatty acid binding protein (LFABP) and an alignment of amino acid sequences of all known species have been used to demonstrate two groups or sub-classes. Based on estimates at neutral pH and the electrostatic field calculated using the crystal coordinates, some evidence of changes that occur in going from holo- to apo-forms has been obtained. LFABP belongs to a large family frequently referred to as the intracellular lipid binding proteins or iLBPs. LFABP, unlike other family members, has two fatty acid binding sites. The two cavity sites have been reviewed and arguments for interactions between the sites are presented. Based on the crystal structure of rat LFABP, differences between the A and B groups have been postulated. Last of all, hypothetical models have been built of complexes of LFABP and heme, and LFABP and oleoyl CoA. In both cases, the stoichiometry is one to one and the models show why this is likely. PMID:10570240

  18. UV-induced cross-linking of abscisic acid to binding proteins

    Conditions for UV-induced cross-linking of abscisic acid (ABA) through its enone chromophore to binding proteins were evaluated. The effects of a UV-light band between 260 and 530 nm on both unconjugated and protein-conjugated ABA, as well as on anti-ABA antibodies as models of ABA-binding proteins were determined. UV irradiation caused both isomerization and photolysis of ABA, but increasing the lower irradiation boundary to 345 nm strongly reduced photolysis and largely prevented isomerization. When conjugated to alkaline phosphatase (AP), ABA remained stable when using either a 320 or a 345 nm filter. At these wavelengths both binding of ABA to antibodies as well as AP enzymatic activity were maintained. UV-induced cross-linking of monoclonal anti-ABA antibodies to immobilized ABA was analysed by immunoassays. Optimal cross-linking was achieved after a 5 min irradiation period at 0°, using a long pass, cut-on filter to quench wavelengths below 290 nm. This cross-linking faithfully reflected cognate binding activity. (author)

  19. Renal Liver-Type Fatty Acid Binding Protein (L-FABP) Attenuates Acute Kidney Injury in Aristolochic Acid Nephrotoxicity

    Matsui, Katsuomi; Kamijo-Ikemorif, Atsuko; Sugaya, Takeshi; Yasuda, Takashi; Kimura, Kenjiro

    2011-01-01

    Injection of aristolochic acid (AA) in mice causes AA-induced nephrotoxicity, in which oxidative stress contributes to development of tubulointerstitial damage (TID). Liver-type fatty acid binding protein (L-FABP) is expressed in human proximal tubules and has an endogenous antioxidative function. The renoprotection of renal L-FABP was examined in a model of AA-induced nephrotoxicity. Established human L-FABP (hL-FABP) transgenic (Tg) mice and wild-type (WT) mice were treated with AA for up t...

  20. Expression Pattern of Fatty Acid Binding Proteins in Celiac Disease Enteropathy

    Natalia M. Bottasso Arias

    2015-01-01

    Full Text Available Celiac disease (CD is an immune-mediated enteropathy that develops in genetically susceptible individuals following exposure to dietary gluten. Severe changes at the intestinal mucosa observed in untreated CD patients are linked to changes in the level and in the pattern of expression of different genes. Fully differentiated epithelial cells express two isoforms of fatty acid binding proteins (FABPs: intestinal and liver, IFABP and LFABP, respectively. These proteins bind and transport long chain fatty acids and also have other important biological roles in signaling pathways, particularly those related to PPARγ and inflammatory processes. Herein, we analyze the serum levels of IFABP and characterize the expression of both FABPs at protein and mRNA level in small intestinal mucosa in severe enteropathy and normal tissue. As a result, we observed higher levels of circulating IFABP in untreated CD patients compared with controls and patients on gluten-free diet. In duodenal mucosa a differential FABPs expression pattern was observed with a reduction in mRNA levels compared to controls explained by the epithelium loss in severe enteropathy. In conclusion, we report changes in FABPs’ expression pattern in severe enteropathy. Consequently, there might be alterations in lipid metabolism and the inflammatory process in the small intestinal mucosa.

  1. Expression Pattern of Fatty Acid Binding Proteins in Celiac Disease Enteropathy.

    Bottasso Arias, Natalia M; García, Marina; Bondar, Constanza; Guzman, Luciana; Redondo, Agustina; Chopita, Nestor; Córsico, Betina; Chirdo, Fernando G

    2015-01-01

    Celiac disease (CD) is an immune-mediated enteropathy that develops in genetically susceptible individuals following exposure to dietary gluten. Severe changes at the intestinal mucosa observed in untreated CD patients are linked to changes in the level and in the pattern of expression of different genes. Fully differentiated epithelial cells express two isoforms of fatty acid binding proteins (FABPs): intestinal and liver, IFABP and LFABP, respectively. These proteins bind and transport long chain fatty acids and also have other important biological roles in signaling pathways, particularly those related to PPARγ and inflammatory processes. Herein, we analyze the serum levels of IFABP and characterize the expression of both FABPs at protein and mRNA level in small intestinal mucosa in severe enteropathy and normal tissue. As a result, we observed higher levels of circulating IFABP in untreated CD patients compared with controls and patients on gluten-free diet. In duodenal mucosa a differential FABPs expression pattern was observed with a reduction in mRNA levels compared to controls explained by the epithelium loss in severe enteropathy. In conclusion, we report changes in FABPs' expression pattern in severe enteropathy. Consequently, there might be alterations in lipid metabolism and the inflammatory process in the small intestinal mucosa. PMID:26346822

  2. Clinical significance of urinary liver-type fatty acid binding protein at various stages of nephropathy

    Viswanathan, V.; S. Sivakumar; Sekar, V; Umapathy, D.; Kumpatla, S.

    2015-01-01

    This cross-sectional study was to evaluate the levels of urinary liver-type fatty acid binding protein (u-LFABP pg/mg urine creatinine ratio) at different stages of diabetic nephropathy and to see its correlation with other clinical parameters in South Indian patients with type 2 diabetes mellitus (T2DM). A total of 65 (M: F; 42:23) T2DM subjects were divided into three groups, and were compared with 13 (M: F; 3:10) nondiabetic controls. The study groups were as follows: normoalbuminuric (n =...

  3. Increased susceptibility to diet-induced gallstones in liver fatty acid binding protein knockout mices⃞

    Xie, Yan; Newberry, Elizabeth P.; Kennedy, Susan M; Luo, Jianyang; Davidson, Nicholas O.

    2009-01-01

    Quantitative trait mapping identified a locus colocalizing with L-Fabp, encoding liver fatty acid binding protein, as a positional candidate for murine gallstone susceptibility. When fed a lithogenic diet (LD) for 2 weeks, L-Fabp−/− mice became hypercholesterolemic with increased hepatic VLDL cholesterol secretion. Seventy-five percent of L-Fabp−/− mice developed solid gallstones compared with 6% of wild-type mice with an increased gallstone score (3.29 versus 0.62, respectively; P < 0.01). H...

  4. Preparation, crystallization and preliminary X-ray diffraction analysis of two intestinal fatty-acid binding proteins in the presence of 11-(dansylamino)undecanoic acid

    Intestinal fatty-acid binding proteins from human and rat have been crystallized in complex with the fluorescent probe 11-(dansylamino)undecanoic acid. Diffraction data for the crystals were collected to 1.8 Å resolution (human) and 1.6 Å resolution (rat). Fatty-acid binding proteins (FABPs) are abundantly expressed proteins that bind a range of lipophilic molecules. They have been implicated in the import and intracellular distribution of their ligands and have been linked with metabolic and inflammatory responses in the cells in which they are expressed. Despite their high sequence identity, human intestinal FABP (hIFABP) and rat intestinal FABP (rIFABP) bind some ligands with different affinities. In order to address the structural basis of this differential binding, diffraction-quality crystals have been obtained of hIFABP and rIFABP in complex with the fluorescent fatty-acid analogue 11-(dansylamino)undecanoic acid

  5. Fatty acid binding protein 7 and n-3 poly unsaturated fatty acid supply in early rat brain development.

    Maximin, Elise; Langelier, Bénédicte; Aïoun, Josiane; Al-Gubory, Kaïs H; Bordat, Christian; Lavialle, Monique; Heberden, Christine

    2016-03-01

    Fatty acid binding protein 7 (FABP7), abundant in the embryonic brain, binds with the highest affinity to docosahexaenoic acid (DHA) and is expressed in the early stages of embryogenesis. Here, we have examined the consequences of the exposure to different DHA levels and of the in utero depletion of FABP7 on early rat brain development. Neurodevelopment was evaluated through the contents of two proteins, connexin 43 (Cx43) and cyclin-dependent kinase 5 (CDK5), both involved in neuroblast proliferation, differentiation, and migration. The dams were fed with diets presenting different DHA contents, from deficiency to supplementation. DHA brain embryos contents already differed at embryonic day 11.5 and the differences kept increasing with time. Cx43 and CDK5 contents were positively associated with the brain DHA levels. When FABP7 was depleted in vivo by injections of siRNA in the telencephalon, the enhancement of the contents of both proteins was lost in supplemented animals, but FABP7 depletion did not modify phospholipid compositions regardless of the diets. Thus, FABP7 is a necessary mediator of the effect of DHA on these proteins synthesis, but its role in DHA uptake is not critical, although FABP7 is localized in phospholipid-rich areas. Our study shows that high contents of DHA associated with FABP7 are necessary to promote early brain development, which prompted us to recommend DHA supplementation early in pregnancy. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 287-297, 2016. PMID:26037116

  6. Fatty acid binding protein 1 is related with development of aspirin-exacerbated respiratory disease.

    Tae-Hoon Kim

    Full Text Available BACKGROUND: Aspirin-exacerbated respiratory disease (AERD refers to the development of bronchoconstriction in asthmatics following the ingestion of aspirin. Although alterations in eicosanoid metabolites play a role in AERD, other immune or inflammatory mechanisms may be involved. We aimed to identify proteins that were differentially expressed in nasal polyps between patients with AERD and aspirin-tolerant asthma (ATA. METHODOLOGY/PRINCIPAL FINDINGS: Two-dimensional electrophoresis was adopted for differential display proteomics. Proteins were identified by liquid chromatography-tandem mass spectrometry (LC-MS. Western blotting and immunohistochemical staining were performed to compare the amount of fatty acid-binding protein 1 (FABP1 in the nasal polyps of patients with AERD and ATA. Fifteen proteins were significantly up- (seven spots or down-regulated in the nasal polyps of patients with AERD (n = 5 compared to those with ATA (n = 8. LC-MS revealed an increase in seven proteins expression and a decrease in eight proteins expression in patients with AERD compared to those with ATA (P = 0.003-0.045. FABP1-expression based on immunoblotting and immunohistochemical analysis was significantly higher in the nasal polyps of patients with AERD compared to that in patients with ATA. FABP1 was observed in epithelial, eosinophils, macrophages, and the smooth-muscle cells of blood vessels in the polyps. CONCLUSIONS/SIGNIFICANCE: Our results indicate that alterations in 15 proteins, including FABP1, may be related to the development of AERD.

  7. Standard in vitro assays for protein-nucleic acid interactions--gel shift assays for RNA and DNA binding.

    Mitchell, Sarah F; Lorsch, Jon R

    2014-01-01

    The characterization of protein-nucleic acid interactions is necessary for the study of a wide variety of biological processes. One straightforward and widely used approach to this problem is the electrophoretic mobility shift assay (EMSA), in which the binding of a nucleic acid to one or more proteins changes its mobility through a nondenaturing gel matrix. Usually, the mobility of the nucleic acid is reduced, but examples of increased mobility do exist. This type of assay can be used to investigate the affinity of the interaction between the protein and nucleic acid, the specificity of the interaction, the minimal binding site, and the kinetics of the interaction. One particular advantage of EMSA is the ability to analyze multiple proteins, or protein complexes, binding to nucleic acids. This assay is relatively quick and easy and utilizes equipment available in most laboratories; however, there are many variables that can only be determined empirically; therefore, optimization is necessary and can be highly dependent upon the system. The protocol described here is for the poly(A)-binding protein (PABP) binding to an unstructured RNA probe of 43 bases. While this may be a useful protocol for some additional assays, it is recommended that both reaction conditions and gel running conditions be tailored to the individual interaction to be probed. PMID:24674072

  8. Diet-induced alterations in intestinal and extrahepatic lipid metabolism in liver fatty acid binding protein knockout mice

    Newberry, Elizabeth P.; Kennedy, Susan M; Xie, Yan; Luo, Jianyang; Davidson, Nicholas O.

    2008-01-01

    Liver fatty acid binding protein (L-FABP) is highly expressed in both enterocytes and hepatocytes and binds multiple ligands, including saturated (SFA), unsaturated fatty acids (PUFA), and cholesterol. L-fabp−/− mice were protected against obesity and hepatic steatosis on a high saturated fat (SF), high cholesterol “Western” diet and manifested a similar phenotype when fed with a high SF, low cholesterol diet. There were no significant differences in fecal fat content or food consumption betw...

  9. Structural analysis of site-directed mutants of cellular retinoic acid-binding protein II addresses the relationship between structural integrity and ligand binding

    Vaezeslami, Soheila [Rigaku Americas Corporation, 9009 New Trails Drive, The Woodlands, TX 77381 (United States); Jia, Xiaofei; Vasileiou, Chrysoula; Borhan, Babak; Geiger, James H., E-mail: geiger@chemistry.msu.edu [Chemistry Department, Michigan State University, East Lansing, MI 48824-1322 (United States); Rigaku Americas Corporation, 9009 New Trails Drive, The Woodlands, TX 77381 (United States)

    2008-12-01

    A water network stabilizes the structure of cellular retionic acid binding protein II. The structural integrity of cellular retinoic acid-binding protein II (CRABPII) has been investigated using the crystal structures of CRABPII mutants. The overall fold was well maintained by these CRABPII mutants, each of which carried multiple different mutations. A water-mediated network is found to be present across the large binding cavity, extending from Arg111 deep inside the cavity to the α2 helix at its entrance. This chain of interactions acts as a ‘pillar’ that maintains the integrity of the protein. The disruption of the water network upon loss of Arg111 leads to decreased structural integrity of the protein. A water-mediated network can be re-established by introducing the hydrophilic Glu121 inside the cavity, which results in a rigid protein with the α2 helix adopting an altered conformation compared with wild-type CRABPII.

  10. Liver fatty acid binding protein (L-Fabp) modifies intestinal fatty acid composition and adenoma formation in ApcMin/+ mice

    Dharmarajan, Sekhar; Newberry, Elizabeth P.; Montenegro, Grace; Nalbantoglu, ILKe; Davis, Victoria R.; Clanahan, Michael J.; Blanc, Valerie; XIE, Yan; Luo, Jianyang; Fleshman, James W.; Kennedy, Susan,; Nicholas O. Davidson

    2013-01-01

    Evidence suggests a relationship between dietary fat intake, obesity and colorectal cancer, implying a role for fatty acid (FA) metabolism in intestinal tumorigenesis that is incompletely understood. Liver fatty acid binding protein (L-Fabp), a dominant intestinal FA binding protein, regulates intestinal FA trafficking and metabolism and L-Fabp deletion attenuates diet-induced obesity. Here we examined whether changes in intestinal FA metabolism following L-Fabp deletion modify adenoma develo...

  11. Transcriptional modulation of hepatic lipoprotein assembly and secretion : coordinate regulation of the liver-fatty acid binding protein and microsomal triglyceride transfer protein genes

    Spann, Nathanael J.

    2006-01-01

    Hepatic production of apolipoprotein (apo) B-containing lipoproteins provides a means to transport essential lipids and fat-soluble nutrients to peripheral tissues for utilization and storage. Liver-fatty acid binding protein (L-FABP) and microsomal triglyceride transfer protein (MTP) bind fatty acids and glycerolipids, respectively and facilitate their transfer into the VLDL assembly and secretion pathway. Sequence analysis reveals that the proximal promoter regions of L-FABP and MTP contain...

  12. Fatty-acid binding proteins modulate sleep and enhance long-term memory consolidation in Drosophila.

    Jason R Gerstner

    Full Text Available Sleep is thought to be important for memory consolidation, since sleep deprivation has been shown to interfere with memory processing. However, the effects of augmenting sleep on memory formation are not well known, and testing the role of sleep in memory enhancement has been limited to pharmacological and behavioral approaches. Here we test the effect of overexpressing the brain-type fatty acid binding protein (Fabp7 on sleep and long-term memory (LTM formation in Drosophila melanogaster. Transgenic flies carrying the murine Fabp7 or the Drosophila homologue dFabp had reduced baseline sleep but normal LTM, while Fabp induction produced increases in both net sleep and LTM. We also define a post-training consolidation "window" that is sufficient for the observed Fabp-mediated memory enhancement. Since Fabp overexpression increases consolidated daytime sleep bouts, these data support a role for longer naps in improving memory and provide a novel role for lipid-binding proteins in regulating memory consolidation concurrently with changes in behavioral state.

  13. Involvement of Fatty Acid Binding Protein 5 and PPARβ/δ in Prostate Cancer Cell Growth

    Elwin Morgan

    2010-01-01

    Full Text Available Fatty acid binding protein 5 (FABP5 delivers ligands from the cytosol directly to the nuclear receptor PPARβ/δ and thus facilitates the ligation and enhances the transcriptional activity of the receptor. We show here that expression levels of both FABP5 and PPARβ/δ are correlated with the tumorigenic potential of prostate cancer cell lines. We show further that FABP5 comprises a direct target gene for PPARβ/δ and thus the binding protein and its cognate receptor are engaged in a positive feedback loop. The observations demonstrate that, similarly to effects observed in mammary carcinomas, activation of the FABP5/PPARβ/δ pathway induces PPARβ/δ target genes involved in cell survival and growth and enhances cell proliferation and anchorage-independent growth in prostate cancer cells. Furthermore, the data show that downregulation of either FABP5 or PPARβ/δ inhibits the growth of the highly malignant prostate cancer PC3M cells. These studies suggest that the FABP5/PPARβ/δ pathway may play a general role in facilitating tumor progression and that inhibition of the pathway may comprise a novel strategy in treatment of cancer.

  14. Structure of the human-heart fatty-acid-binding protein 3 in complex with the fluorescent probe 1-anilinonaphthalene-8-sulphonic acid

    Hirose, Mika; Sugiyama, Shigeru, E-mail: sugiyama@chem.eng.osaka-u.ac.jp [Lipid Active Structure Project, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan); Osaka University, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan); Ishida, Hanako; Niiyama, Mayumi [Lipid Active Structure Project, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan); Osaka University, 2-1 Yamadaoka, Suita 565-0871 (Japan); Matsuoka, Daisuke; Hara, Toshiaki [Lipid Active Structure Project, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan); Osaka University, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan); Mizohata, Eiichi [Osaka University, 2-1 Yamadaoka, Suita 565-0871 (Japan); Murakami, Satoshi [Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Kanagaw 226-8501 (Japan); Inoue, Tsuyoshi [Osaka University, 2-1 Yamadaoka, Suita 565-0871 (Japan); Matsuoka, Shigeru; Murata, Michio [Lipid Active Structure Project, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan); Osaka University, 1-1 Machikaneyama-cho, Toyonaka 560-0043 (Japan)

    2013-11-01

    The crystal structure of human-heart-type fatty-acid-binding protein in complex with anilinonaphthalene-8-sulfonate was solved at 2.15 Å resolution revealing the detailed binding mechanism of the fluorescent probe 1-anilinonaphthalene-8-sulfonate. Heart-type fatty-acid-binding protein (FABP3), which is a cytosolic protein abundantly found in cardiomyocytes, plays a role in trafficking fatty acids throughout cellular compartments by reversibly binding intracellular fatty acids with relatively high affinity. The fluorescent probe 1-anilinonaphthalene-8-sulfonate (ANS) is extensively utilized for examining the interaction of ligands with fatty-acid-binding proteins. The X-ray structure of FABP3 was determined in the presence of ANS and revealed the detailed ANS-binding mechanism. Furthermore, four water molecules were clearly identified in the binding cavity. Through these water molecules, the bound ANS molecule forms indirect hydrogen-bond interactions with FABP3. The adipocyte-type fatty-acid-binding protein (FABP4) exhibits 67% sequence identity with FABP3 and its crystal structure is almost the same as that of FABP3. However, FABP4 can bind with a higher affinity to ANS than FABP3. To understand the difference in their ligand specificities, a structural comparison was performed between FABP3–ANS and FABP4–ANS complexes. The result revealed that the orientation of ANS binding to FABP3 is completely opposite to that of ANS binding to FABP4, and the substitution of valine in FABP4 to leucine in FABP3 may result in greater steric hindrance between the side-chain of Leu115 and the aniline ring of ANS.

  15. Structure of the human-heart fatty-acid-binding protein 3 in complex with the fluorescent probe 1-anilinonaphthalene-8-sulphonic acid

    The crystal structure of human-heart-type fatty-acid-binding protein in complex with anilinonaphthalene-8-sulfonate was solved at 2.15 Å resolution revealing the detailed binding mechanism of the fluorescent probe 1-anilinonaphthalene-8-sulfonate. Heart-type fatty-acid-binding protein (FABP3), which is a cytosolic protein abundantly found in cardiomyocytes, plays a role in trafficking fatty acids throughout cellular compartments by reversibly binding intracellular fatty acids with relatively high affinity. The fluorescent probe 1-anilinonaphthalene-8-sulfonate (ANS) is extensively utilized for examining the interaction of ligands with fatty-acid-binding proteins. The X-ray structure of FABP3 was determined in the presence of ANS and revealed the detailed ANS-binding mechanism. Furthermore, four water molecules were clearly identified in the binding cavity. Through these water molecules, the bound ANS molecule forms indirect hydrogen-bond interactions with FABP3. The adipocyte-type fatty-acid-binding protein (FABP4) exhibits 67% sequence identity with FABP3 and its crystal structure is almost the same as that of FABP3. However, FABP4 can bind with a higher affinity to ANS than FABP3. To understand the difference in their ligand specificities, a structural comparison was performed between FABP3–ANS and FABP4–ANS complexes. The result revealed that the orientation of ANS binding to FABP3 is completely opposite to that of ANS binding to FABP4, and the substitution of valine in FABP4 to leucine in FABP3 may result in greater steric hindrance between the side-chain of Leu115 and the aniline ring of ANS

  16. CLINICAL EXPERIENCE OF CANCER IMMUNOTHERAPY INTEGRATED WITH OLEIC ACID COMPLEXED WITH DE-GLYCOSYLATED VITAMIN D BINDING PROTEIN

    Emma Ward; Rodney Smith; Branca, Jacopo J. V.; David Noakes; Gabriele Morucci; Lynda Thyer

    2014-01-01

    Proteins highly represented in milk such as α-lactalbumin and lactoferrin bind Oleic Acid (OA) to form complexes with selective anti-tumor activity. A protein present in milk, colostrum and blood, vitamin D binding protein is the precursor of a potent Macrophage Activating Factor (GcMAF) and in analogy with other OA-protein complexes, we proposed that OA-GcMAF could demonstrate a greater immunotherapeutic activity than that of GcMAF alone. We describe a preliminary experience treating p...

  17. Liver Fatty acid binding protein (L-Fabp) modulates murine stellate cell activation and diet induced nonalcoholic fatty liver disease

    Chen, Anping; Tang, Youcai; Davis, Victoria; Hsu, Fong-Fu; Kennedy, Susan M; Song, Haowei; Turk, John; Brunt, Elizabeth M.; Newberry, Elizabeth P.; Davidson, Nicholas O.

    2013-01-01

    Activation of hepatic stellate cells (HSCs) is crucial to the development of fibrosis in nonalcoholic fatty liver disease. Quiescent HSCs contain lipid droplets (LDs), whose depletion upon activation induces a fibrogenic gene program. Here we show that liver fatty acid-binding protein (L-Fabp), an abundant cytosolic protein that modulates fatty acid (FA) metabolism in enterocytes and hepatocytes also modulates HSC FA utilization and in turn regulates the fibrogenic program. L-Fabp expression ...

  18. Brain-type and liver-type fatty acid-binding proteins: new tumor markers for renal cancer?

    Moch Holger; Miller Kurt; Johannsen Manfred; Lein Michael; Jung Monika; Tölle Angelika; Jung Klaus; Kristiansen Glen

    2009-01-01

    Abstract Background Renal cell carcinoma (RCC) is the most common renal neoplasm. Cancer tissue is often characterized by altered energy regulation. Fatty acid-binding proteins (FABP) are involved in the intracellular transport of fatty acids (FA). We examined the level of brain-type (B) and liver-type (L) FABP mRNA and the protein expression profiles of both FABPs in renal cell carcinoma. Methods Paired tissue samples of cancerous and noncancerous kidney parts were investigated. Quantitative...

  19. Role of a liver fatty acid-binding protein gene in lipid metabolism in chicken hepatocytes.

    Gao, G L; Na, W; Wang, Y X; Zhang, H F; Li, H; Wang, Q G

    2015-01-01

    This study investigated the role of the chicken liver fatty acid-binding protein (L-FABP) gene in lipid metabolism in hepatocytes, and the regulatory relationships between L-FABP and genes related to lipid metabolism. The short hairpin RNA (shRNA) interference vector with L-FABP and an eukaryotic expression vector were used. Chicken hepatocytes were subjected to shRNA-mediated knockdown or L-FABP cDNA overexpression. Expression levels of lipid metabolism-related genes and biochemical parameters were detected 24, 36, 48, 60, and 72 h after transfection with the interference or overexpression plasmids for L-FABP, PPARα and L-BABP expression levels, and the total amount of cholesterol, were significantly affected by L-FABP expression. L-FABP may affect lipid metabolism by regulating PPARα and L-BABP in chicken hepatocytes. PMID:25966259

  20. Loss of intracellular lipid binding proteins differentially impacts saturated fatty acid uptake and nuclear targeting in mouse hepatocytes

    Storey, Stephen M.; McIntosh, Avery L.; Huang, Huan; Martin, Gregory G.; Landrock, Kerstin K.; Landrock, Danilo; Payne, H. Ross; Kier, Ann B.; Schroeder, Friedhelm

    2012-01-01

    The liver expresses high levels of two proteins with high affinity for long-chain fatty acids (LCFAs): liver fatty acid binding protein (L-FABP) and sterol carrier protein-2 (SCP-2). Real-time confocal microscopy of cultured primary hepatocytes from gene-ablated (L-FABP, SCP-2/SCP-x, and L-FABP/SCP-2/SCP-x null) mice showed that the loss of L-FABP reduced cellular uptake of 12-N-methyl-(7-nitrobenz-2-oxa-1,3-diazo)-aminostearic acid (a fluorescent-saturated LCFA analog) by ∼50%. Importantly, ...

  1. Enterocyte fatty acid-binding proteins (FABPs): different functions of liver and intestinal FABPs in the intestine.

    Gajda, Angela M; Storch, Judith

    2015-02-01

    Fatty acid-binding proteins (FABP) are highly abundant cytosolic proteins that are expressed in most mammalian tissues. In the intestinal enterocyte, both liver- (LFABP; FABP1) and intestinal FABPs (IFABP; FABP2) are expressed. These proteins display high-affinity binding for long-chain fatty acids (FA) and other hydrophobic ligands; thus, they are believed to be involved with uptake and trafficking of lipids in the intestine. In vitro studies have identified differences in ligand-binding stoichiometry and specificity, and in mechanisms of FA transfer to membranes, and it has been hypothesized that LFABP and IFABP have different functions in the enterocyte. Studies directly comparing LFABP- and IFABP-null mice have revealed markedly different phenotypes, indicating that these proteins indeed have different functions in intestinal lipid metabolism and whole body energy homeostasis. In this review, we discuss the evolving knowledge of the functions of LFABP and IFABP in the intestinal enterocyte. PMID:25458898

  2. A nuclear magnetic resonance-based structural rationale for contrasting stoichiometry and ligand binding site(s) in fatty acid-binding proteins.

    He, Yan; Estephan, Rima; Yang, Xiaomin; Vela, Adriana; Wang, Hsin; Bernard, Cédric; Stark, Ruth E

    2011-03-01

    Liver fatty acid-binding protein (LFABP) is a 14 kDa cytosolic polypeptide, differing from other family members in the number of ligand binding sites, the diversity of bound ligands, and the transfer of fatty acid(s) to membranes primarily via aqueous diffusion rather than direct collisional interactions. Distinct two-dimensional (1)H-(15)N nuclear magnetic resonance (NMR) signals indicative of slowly exchanging LFABP assemblies formed during stepwise ligand titration were exploited, without determining the protein-ligand complex structures, to yield the stoichiometries for the bound ligands, their locations within the protein binding cavity, the sequence of ligand occupation, and the corresponding protein structural accommodations. Chemical shifts were monitored for wild-type LFABP and an R122L/S124A mutant in which electrostatic interactions viewed as being essential to fatty acid binding were removed. For wild-type LFABP, the results compared favorably with the data for previous tertiary structures of oleate-bound wild-type LFABP in crystals and in solution: there are two oleates, one U-shaped ligand that positions the long hydrophobic chain deep within the cavity and another extended structure with the hydrophobic chain facing the cavity and the carboxylate group lying close to the protein surface. The NMR titration validated a prior hypothesis that the first oleate to enter the cavity occupies the internal protein site. In contrast, (1)H and (15)N chemical shift changes supported only one liganded oleate for R122L/S124A LFABP, at an intermediate location within the protein cavity. A rationale based on protein sequence and electrostatics was developed to explain the stoichiometry and binding site trends for LFABPs and to put these findings into context within the larger protein family. PMID:21226535

  3. Conjugated linoleic acid and fatty acid binding protein as antioxidants Ácido linoleico conjugado y proteína transportadora de ácidos grasos como antioxidantes

    V.A. Piergiacomi; Palacios, A.

    2006-01-01

    Studies were carried out to determine the effect of conjugated linoleic acid (CLA) and rat liver cytosolic protein enriched in fatty acid binding protein (FABP) on the non-enzymatic lipid peroxidation of rat liver microsomes. The inhibition of lipid peroxidation was more evident when the FABP containing fraction obtained from CLA-group was used with either kind of microsomes (CLA and control). The chemiluminescence and polyunsaturated fatty acid composition of rat liver microsomes changed aft...

  4. Millisecond Timescale Dynamics of Human Liver Fatty Acid Binding Protein: Testing of Its Relevance to the Ligand Entry Process

    Long, Dong; Yang, Daiwen

    2010-01-01

    For over a decade, scientists have been attempting to know more about the conformational dynamics of fatty acid binding proteins (FABPs), to answer the puzzling question of how ligands could access the internalized binding site(s). Conformational exchange of FABPs on the microsecond to millisecond timescales has been found in many FABPs and offers an important hypothesis for the ligand entry mechanism. Despite the potential significance, the validity of this hypothesis has not been verified y...

  5. Development of a radioiodinated triazolopyrimidine probe for nuclear medical imaging of fatty acid binding protein 4.

    Kantaro Nishigori

    Full Text Available Fatty acid binding protein 4 (FABP4 is the most well-characterized FABP isoform. FABP4 regulates inflammatory pathways in adipocytes and macrophages and is involved in both inflammatory diseases and tumor formation. FABP4 expression was recently reported for glioblastoma, where it may participate in disease malignancy. While FABP4 is a potential molecular imaging target, with the exception of a tritium labeled probe there are no reports of other nuclear imaging probes that target this protein. Here we designed and synthesized a nuclear imaging probe, [123I]TAP1, and evaluated its potential as a FABP4 targeting probe in in vitro and in vivo assays. We focused on the unique structure of a triazolopyrimidine scaffold that lacks a carboxylic acid to design the TAP1 probe that can undergo facilitated delivery across cell membranes. The affinity of synthesized TAP1 was measured using FABP4 and 8-anilino-1-naphthalene sulfonic acid. [125I]TAP1 was synthesized by iododestannylation of a precursor, followed by affinity and selectivity measurements using immobilized FABPs. Biodistributions in normal and C6 glioblastoma-bearing mice were evaluated, and excised tumors were subjected to autoradiography and immunohistochemistry. TAP1 and [125I]TAP1 showed high affinity for FABP4 (Ki = 44.5±9.8 nM, Kd = 69.1±12.3 nM. The FABP4 binding affinity of [125I]TAP1 was 11.5- and 35.5-fold higher than for FABP3 and FABP5, respectively. In an in vivo study [125I]TAP1 displayed high stability against deiodination and degradation, and moderate radioactivity accumulation in C6 tumors (1.37±0.24% dose/g 3 hr after injection. The radioactivity distribution profile in tumors partially corresponded to the FABP4 positive area and was also affected by perfusion. The results indicate that [125I]TAP1 could detect FABP4 in vitro and partly in vivo. As such, [125I]TAP1 is a promising lead compound for further refinement for use in in vivo FABP4 imaging.

  6. Intrinsic nucleic acid dynamics modulates HIV-1 nucleocapsid protein binding to its targets.

    Bazzi, Ali; Zargarian, Loussiné; Chaminade, Françoise; De Rocquigny, Hugues; René, Brigitte; Mély, Yves; Fossé, Philippe; Mauffret, Olivier

    2012-01-01

    HIV-1 nucleocapsid protein (NC) is involved in the rearrangement of nucleic acids occurring in key steps of reverse transcription. The protein, through its two zinc fingers, interacts preferentially with unpaired guanines in single-stranded sequences. In mini-cTAR stem-loop, which corresponds to the top half of the cDNA copy of the transactivation response element of the HIV-1 genome, NC was found to exhibit a clear preference for the TGG sequence at the bottom of mini-cTAR stem. To further understand how this site was selected among several potential binding sites containing unpaired guanines, we probed the intrinsic dynamics of mini-cTAR using (13)C relaxation measurements. Results of spin relaxation time measurements have been analyzed using the model-free formalism and completed by dispersion relaxation measurements. Our data indicate that the preferentially recognized guanine in the lower part of the stem is exempt of conformational exchange and highly mobile. In contrast, the unrecognized unpaired guanines of mini-cTAR are involved in conformational exchange, probably related to transient base-pairs. These findings support the notion that NC preferentially recognizes unpaired guanines exhibiting a high degree of mobility. The ability of NC to discriminate between close sequences through their dynamic properties contributes to understanding how NC recognizes specific sites within the HIV genome. PMID:22745685

  7. Noninvasive measurement of fecal calprotectin and serum amyloid A combined with intestinal fatty acid-binding protein in necrotizing enterocolitis.

    Reisinger, K.W.; Zee, D.C. van der; Brouwers, H.A.A.; Kramer, B.W.; Heurn, L.W.E. van; Buurman, W.A.; Derikx, J.P.

    2012-01-01

    BACKGROUND: Diagnosis of necrotizing enterocolitis (NEC), prevalent in premature infants, remains challenging. Enterocyte damage in NEC can be assessed by intestinal fatty acid-binding protein (I-FABP), with a sensitivity of 93% and a specificity of 90%. Numerous markers of inflammation are known, s

  8. Noninvasive measurement of fecal calprotectin and serum amyloid A combined with intestinal fatty acid-binding protein in necrotizing enterocolitis

    Reisinger, Kostan W.; Van der Zee, David C.; Brouwers, Hens A. A.; Kramer, Boris W.; van Heurn, L. W. Ernest; Buurman, Wim A.; Derikx, Joep P. M.

    2012-01-01

    Background: Diagnosis of necrotizing enterocolitis (NEC), prevalent in premature infants, remains challenging. Enterocyte damage in NEC can be assessed by intestinal fatty acid-binding protein (I-FABP), with a sensitivity of 93% and a specificity of 90%. Numerous markers of inflammation are known, s

  9. Fatty Acid binding protein 4 is associated with carotid atherosclerosis and outcome in patients with acute ischemic stroke

    Holm, Sverre; Ueland, Thor; Dahl, Tuva B;

    2011-01-01

    Fatty acid binding protein 4 (FABP4) has been shown to play an important role in macrophage cholesterol trafficking and associated inflammation. To further elucidate the role of FABP4 in atherogenesis in humans, we examined the regulation of FABP4 in carotid atherosclerosis and ischemic stroke....

  10. Urinary liver-type fatty acid-binding protein predicts progression to nephropathy in type 1 diabetic patients

    Nielsen, Stine Elkjaer; Sugaya, Takeshi; Hovind, Peter;

    2010-01-01

    Urinary liver-type fatty acid-binding protein (u-LFABP) is a marker of tubulointerstitial inflammation and has been shown to be increased in patients with type 1 diabetes and is further increased in patients who progress to micro- and macroalbuminuria. Our aim was to evaluate u-LFABP as a predictor...

  11. The effect of charge reversal mutations in the alpha-helical region of liver fatty acid binding protein on the binding of fatty-acyl CoAs, lysophospholipids and bile acids.

    Hagan, Robert M; Davies, Joanna K; Wilton, David C

    2002-10-01

    Liver fatty acid binding protein (LFABP) is unique among the various types of FABPs in that it can bind a variety of ligands in addition to fatty acids. LFABP is able to bind long chain fatty acids with a 2:1 stoichiometry and the crystal structure has identified two fatty acid binding sites in the binding cavity. The presumed primary site (site 1) involves the fatty acid binding with the carboxylate group buried in the cavity whereas the fatty acid at site 2 has the carboxylate group solvent-exposed within the ligand portal region and in the vicinity of alpha-helix II. The alpha-helical region contains three cationic residues, K20, K31, K33 and modelling studies suggest that K31 on alpha-helix II could make an electrostatic contribution to anionic ligands binding to site 2. The preparation of three charge reversal mutants of LFABP, K20E, K31E and K33E has allowed an investigation of the role of site 2 in ligand binding, particularly those ligands with a bulky anionic head group. The binding of oleoyl CoA, lysophosphatidic acid, lysophosphatidylcholine, lithocholic acid and taurolithocholate 3-sulphate to LFABP has been studied using the alpha-helical mutants. The results support the concept that such ligands bind at site 2 of LFABP where solvent exposure allows the accommodation of their bulky anionic group. PMID:12479568

  12. Receptor binding proteins of Listeria monocytogenes bacteriophages A118 and P35 recognize serovar-specific teichoic acids

    Adsorption of a bacteriophage to the host requires recognition of a cell wall-associated receptor by a receptor binding protein (RBP). This recognition is specific, and high affinity binding is essential for efficient virus attachment. The molecular details of phage adsorption to the Gram-positive cell are poorly understood. We present the first description of receptor binding proteins and a tail tip structure for the siphovirus group infecting Listeria monocytogenes. The host-range determining factors in two phages, A118 and P35 specific for L. monocytogenes serovar 1/2 have been determined. Two proteins were identified as RBPs in phage A118. Rhamnose residues in wall teichoic acids represent the binding ligands for both proteins. In phage P35, protein gp16 could be identified as RBP and the role of both rhamnose and N-acetylglucosamine in phage adsorption was confirmed. Immunogold-labeling and transmission electron microscopy allowed the creation of a topological model of the A118 phage tail. - Highlights: • We present the first description of receptor binding proteins and a tail tip structure for the Siphovirus group infecting Listeria monocytogenes. • The host-range determining factors in two phages, A118 and P35 specific for L. monocytogenes serovar 1/2 have been determined. • Rhamnose residues in wall teichoic acids represent the binding ligands for both receptor binding proteins in phage A118. • Rhamnose and N-acetylglucosamine are required for adsorption of phage P35. • We preset a topological model of the A118 phage tail

  13. Receptor binding proteins of Listeria monocytogenes bacteriophages A118 and P35 recognize serovar-specific teichoic acids

    Bielmann, Regula; Habann, Matthias; Eugster, Marcel R. [Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich (Switzerland); Lurz, Rudi [Max-Planck Institute for Molecular Genetics, 14195 Berlin (Germany); Calendar, Richard [Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3202 (United States); Klumpp, Jochen, E-mail: jochen.klumpp@hest.ethz.ch [Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich (Switzerland); Loessner, Martin J. [Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich (Switzerland)

    2015-03-15

    Adsorption of a bacteriophage to the host requires recognition of a cell wall-associated receptor by a receptor binding protein (RBP). This recognition is specific, and high affinity binding is essential for efficient virus attachment. The molecular details of phage adsorption to the Gram-positive cell are poorly understood. We present the first description of receptor binding proteins and a tail tip structure for the siphovirus group infecting Listeria monocytogenes. The host-range determining factors in two phages, A118 and P35 specific for L. monocytogenes serovar 1/2 have been determined. Two proteins were identified as RBPs in phage A118. Rhamnose residues in wall teichoic acids represent the binding ligands for both proteins. In phage P35, protein gp16 could be identified as RBP and the role of both rhamnose and N-acetylglucosamine in phage adsorption was confirmed. Immunogold-labeling and transmission electron microscopy allowed the creation of a topological model of the A118 phage tail. - Highlights: • We present the first description of receptor binding proteins and a tail tip structure for the Siphovirus group infecting Listeria monocytogenes. • The host-range determining factors in two phages, A118 and P35 specific for L. monocytogenes serovar 1/2 have been determined. • Rhamnose residues in wall teichoic acids represent the binding ligands for both receptor binding proteins in phage A118. • Rhamnose and N-acetylglucosamine are required for adsorption of phage P35. • We preset a topological model of the A118 phage tail.

  14. Fatty Acid Binding Protein 5 Modulates Docosahexaenoic Acid-Induced Recovery in Rats Undergoing Spinal Cord Injury.

    Figueroa, Johnny D; Serrano-Illan, Miguel; Licero, Jenniffer; Cordero, Kathia; Miranda, Jorge D; De Leon, Marino

    2016-08-01

    Omega-3 polyunsaturated fatty acids (n-3 PUFAs) promote functional recovery in rats undergoing spinal cord injury (SCI). However, the precise molecular mechanism coupling n-3 PUFAs to neurorestorative responses is not well understood. The aim of the present study was to determine the spatiotemporal expression of fatty acid binding protein 5 (FABP5) after contusive SCI and to investigate whether this protein plays a role in n-3 PUFA-mediated functional recovery post-SCI. We found that SCI resulted in a robust spinal cord up-regulation in FABP5 mRNA levels (556 ± 187%) and protein expression (518 ± 195%), when compared to sham-operated rats, at 7 days post-injury (dpi). This upregulation coincided with significant alterations in the metabolism of fatty acids in the injured spinal cord, as revealed by metabolomics-based lipid analyses. In particular, we found increased levels of the n-3 series PUFAs, particularly docosahexaenoic acid (DHA; 22:6 n-3) and eicosapentaenoic acid (EPA; 20:5 n-3) at 7 dpi. Animals consuming a diet rich in DHA and EPA exhibited a significant upregulation in FABP5 mRNA levels at 7 dpi. Immunofluorescence showed low basal FABP5 immunoreactivity in spinal cord ventral gray matter NeuN(+) neurons of sham-operated rats. SCI resulted in a robust induction of FABP5 in glial (GFAP(+), APC(+), and NG2(+)) and precursor cells (DCX(+), nestin(+)). We found that continuous intrathecal administration of FABP5 silencing with small interfering RNA (2 μg) impaired spontaneous open-field locomotion post-SCI. Further, FABP5 siRNA administration hindered the beneficial effects of DHA to ameliorate functional recovery at 7 dpi. Altogether, our findings suggest that FABP5 may be an important player in the promotion of cellular uptake, transport, and/or metabolism of DHA post-SCI. Given the beneficial roles of n-3 PUFAs in ameliorating functional recovery, we propose that FABP5 is an important contributor to basic repair mechanisms in the

  15. The sialic acid binding activity of the S protein facilitates infection by porcine transmissible gastroenteritis coronavirus

    Enjuanes Luis

    2011-09-01

    Full Text Available Abstract Background Transmissible gastroenteritis virus (TGEV has a sialic acid binding activity that is believed to be important for enteropathogenicity, but that has so far appeared to be dispensable for infection of cultured cells. The aims of this study were to determine the effect of sialic acid binding for the infection of cultured cells under unfavorable conditions, and comparison of TGEV strains and mutants, as well as the avian coronavirus IBV concerning their dependence on the sialic acid binding activity. Methods The infectivity of different viruses was analyzed by a plaque assay after adsorption times of 5, 20, and 60 min. Prior to infection, cultured cells were either treated with neuraminidase to deplete sialic acids from the cell surface, or mock-treated. In a second approach, pre-treatment of the virus with porcine intestinal mucin was performed, followed by the plaque assay after a 5 min adsorption time. A student's t-test was used to verify the significance of the results. Results Desialylation of cells only had a minor effect on the infection by TGEV strain Purdue 46 when an adsorption period of 60 min was allowed for initiation of infection. However, when the adsorption time was reduced to 5 min the infectivity on desialylated cells decreased by more than 60%. A TGEV PUR46 mutant (HAD3 deficient in sialic acid binding showed a 77% lower titer than the parental virus after a 5 min adsorption time. After an adsorption time of 60 min the titer of HAD3 was 58% lower than that of TGEV PUR46. Another TGEV strain, TGEV Miller, and IBV Beaudette showed a reduction in infectivity after neuraminidase treatment of the cultured cells irrespective of the virion adsorption time. Conclusions Our results suggest that the sialic acid binding activity facilitates the infection by TGEV under unfavorable environmental conditions. The dependence on the sialic acid binding activity for an efficient infection differs in the analyzed TGEV strains.

  16. Fatty Acid-binding Proteins Interact with Comparative Gene Identification-58 Linking Lipolysis with Lipid Ligand Shuttling*

    Hofer, Peter; Boeszoermenyi, Andras; Jaeger, Doris; Feiler, Ursula; Arthanari, Haribabu; Mayer, Nicole; Zehender, Fabian; Rechberger, Gerald; Oberer, Monika; Zimmermann, Robert; Lass, Achim; Haemmerle, Guenter; Breinbauer, Rolf; Zechner, Rudolf; Preiss-Landl, Karina

    2015-01-01

    Background: A multiprotein complex designated as lipolysome degrades intracellular triglycerides and contains proteins such as adipose triglyceride lipase (Atgl) and its co-activator Cgi-58. Results: Cgi-58 interacts with fatty acid-binding proteins (Fabps), which impact Atgl-mediated lipolysis and lipid signaling. Conclusion: Fabps modulate Atgl-mediated TG hydrolysis and link lipolysis with intracellular lipid ligand shuttling. Significance: Novel mechanistic insights into the regulation of...

  17. Fatty acid binding protein 4 expression marks a population of adipocyte progenitors in white and brown adipose tissues

    SHAN, Tizhong; Liu, Weiyi; Kuang, Shihuan

    2013-01-01

    Adipose tissues regulate metabolism, reproduction, and life span. The development and growth of adipose tissue are due to increases of both adipocyte cell size and cell number; the latter is mediated by adipocyte progenitors. Various markers have been used to identify either adipocyte progenitors or mature adipocytes. The fatty acid binding protein 4 (FABP4), commonly known as adipocyte protein 2 (aP2), has been extensively used as a marker for differentiated adipocytes. However, whether aP2 ...

  18. Dystrobrevin-binding protein 1 gene (DTNBP1) variants associated with cerebrospinal fluid homovanillic acid and 5-hydroxyindoleacetic acid concentrations in healthy volunteers

    Andreou, Dimitrios; Saetre, Peter; Kähler, Anna K;

    2011-01-01

    The dystrobrevin binding protein-1 (DTNBP1) gene encodes dysbindin-1, a protein involved in neurodevelopmental and neurochemical processes related mainly to the monoamine dopamine. We investigated possible associations between eleven DTNBP1 polymorphisms and cerebrospinal fluid (CSF) concentrations...... of the major dopamine metabolite homovanillic acid (HVA), the major serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), and the major noradrenaline metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in healthy human subjects (n=132). Two polymorphisms, rs2619538 and rs760666, were nominally...

  19. Upregulation of peroxisome proliferator-activated receptors and liver fatty acid binding protein in hepatic cells of broiler chicken supplemented with conjugated linoleic acids

    Suriya Kumari Ramiah; Goh Y. Meng; Mahdi Ebrahimi

    2015-01-01

    Since conjugated linoleic acid (CLA) has structural and physiological characteristics similar to peroxisome proliferators, it is hypothesized that CLA would upregulate peroxisome proliferator-activated receptor (PPAR) and liver fatty acid binding protein (LFABP) in the liver of broiler chicken. The aim of the present study was to determine fatty acid composition of liver in CLA-fed broiler chickens and the genes associated with hepatic lipid metabolism. A total of 180-day-old broiler chicks w...

  20. Branched-chain Amino Acid Biosensing Using Fluorescent Modified Engineered Leucine/Isoleucine/Valine Binding Protein

    Koji Sode

    2007-06-01

    Full Text Available A novel fluorescence sensing system for branched-chain amino acids (BCAAswas developed based on engineered leucine/isoleucine/valine-binding proteins (LIVBPsconjugated with environmentally sensitive fluorescence probes. LIVBP was cloned fromEscherichia coli and Gln149Cys, Gly227Cys, and Gln254Cys mutants were generated bygenetic engineering. The mutant LIVBPs were then modified with environmentallysensitive fluorophores. Based on the fluorescence intensity change observed upon thebinding of the ligands, the MIANS-conjugated Gln149Cys mutant (Gln149Cys-M showedthe highest and most sensitive response. The BCAAs Leu, Ile, and Val can each bemonitored at the sub-micromolar level using Gln149Cys-M. Measurements were alsocarried out on a mixture of BCAFAs and revealed that Gln149Cys-M-based measurementis not significantly affected by the change in the molar ratio of Leu, Ile and Val in thesample. Its high sensitivity and group-specific molecular recognition ability make the newsensing system ideally suited for the measurement of BCAAs and the determination of theFischer ratio, an indicator of hepatic disease involving metabolic dysfunction.

  1. Examination of the Addictive and Behavioral Properties of Fatty Acid-Binding Protein Inhibitor SBFI26

    Thanos, Panayotis K.; Clavin, Brendan H.; Hamilton, John; O’Rourke, Joseph R.; Maher, Thomas; Koumas, Christopher; Miao, Erick; Lankop, Jessenia; Elhage, Aya; Haj-Dahmane, Samir; Deutsch, Dale; Kaczocha, Martin

    2016-01-01

    The therapeutic properties of cannabinoids have been well demonstrated but are overshadowed by such adverse effects as cognitive and motor dysfunction, as well as their potential for addiction. Recent research on the natural lipid ligands of cannabinoid receptors, also known as endocannabinoids, has shed light on the mechanisms of intracellular transport of the endocannabinoid anandamide by fatty acid-binding proteins (FABPs) and subsequent catabolism by fatty acid amide hydrolase. These findings facilitated the recent development of SBFI26, a pharmacological inhibitor of epidermal- and brain-specific FABP5 and FABP7, which effectively increases anandamide signaling. The goal of this study was to examine this compound for any possible rewarding and addictive properties as well as effects on locomotor activity, working/recognition memory, and propensity for sociability and preference for social novelty (SN) given its recently reported anti-inflammatory and analgesic properties. Male C57BL mice were split into four treatment groups and conditioned with 5.0, 20.0, 40.0 mg/kg SBFI26, or vehicle during a conditioned place preference (CPP) paradigm. Following CPP, mice underwent a battery of behavioral tests [open field, novel object recognition (NOR), social interaction (SI), and SN] paired with acute SBFI26 administration. Results showed that SBFI26 did not produce CPP or conditioned place aversion regardless of dose and did not induce any differences in locomotor and exploratory activity during CPP- or SBFI26-paired open field activity. We also observed no differences between treatment groups in NOR, SI, and SN. In conclusion, as SBFI26 was shown previously by our group to have significant analgesic and anti-inflammatory properties, here we show that it does not pose a risk of dependence or motor and cognitive impairment under the conditions tested. PMID:27092087

  2. Examination of the Addictive and Behavioral Properties of Fatty Acid-Binding Protein Inhibitor SBFI26.

    Thanos, Panayotis K; Clavin, Brendan H; Hamilton, John; O'Rourke, Joseph R; Maher, Thomas; Koumas, Christopher; Miao, Erick; Lankop, Jessenia; Elhage, Aya; Haj-Dahmane, Samir; Deutsch, Dale; Kaczocha, Martin

    2016-01-01

    The therapeutic properties of cannabinoids have been well demonstrated but are overshadowed by such adverse effects as cognitive and motor dysfunction, as well as their potential for addiction. Recent research on the natural lipid ligands of cannabinoid receptors, also known as endocannabinoids, has shed light on the mechanisms of intracellular transport of the endocannabinoid anandamide by fatty acid-binding proteins (FABPs) and subsequent catabolism by fatty acid amide hydrolase. These findings facilitated the recent development of SBFI26, a pharmacological inhibitor of epidermal- and brain-specific FABP5 and FABP7, which effectively increases anandamide signaling. The goal of this study was to examine this compound for any possible rewarding and addictive properties as well as effects on locomotor activity, working/recognition memory, and propensity for sociability and preference for social novelty (SN) given its recently reported anti-inflammatory and analgesic properties. Male C57BL mice were split into four treatment groups and conditioned with 5.0, 20.0, 40.0 mg/kg SBFI26, or vehicle during a conditioned place preference (CPP) paradigm. Following CPP, mice underwent a battery of behavioral tests [open field, novel object recognition (NOR), social interaction (SI), and SN] paired with acute SBFI26 administration. Results showed that SBFI26 did not produce CPP or conditioned place aversion regardless of dose and did not induce any differences in locomotor and exploratory activity during CPP- or SBFI26-paired open field activity. We also observed no differences between treatment groups in NOR, SI, and SN. In conclusion, as SBFI26 was shown previously by our group to have significant analgesic and anti-inflammatory properties, here we show that it does not pose a risk of dependence or motor and cognitive impairment under the conditions tested. PMID:27092087

  3. Titration and exchange studies of liver fatty acid-binding protein with 13C-labeled long-chain fatty acids.

    Wang, Hsin; He, Yan; Kroenke, Christopher D; Kodukula, Sarala; Storch, Judith; Palmer, Arthur G; Stark, Ruth E

    2002-04-30

    Uniformly (13)C-labeled long-chain fatty acids were used to probe ligand binding to rat liver fatty acid-binding protein (LFABP), an atypical member of the fatty acid-binding protein (FABP) family that binds more than one molecule of long-chain fatty acid, accommodates a variety of diverse ligands, and exhibits diffusion-mediated lipid transport to membranes. Two sets of (1)H-(13)C resonances were found in a titration series of NMR spectra for oleate-LFABP complexes, indicating that two molecules of the fatty acid are situated in the protein cavity. However, no distinct resonances were observed for the excess fatty acid in solution, suggesting that at least one ligand undergoes rapid exchange with oleate in the bulk solution. An exchange rate of 54 +/- 6 s(-1) between the two sets of resonances was measured directly using (13)C z,z-exchange spectroscopy. In light of these NMR measurements, possible molecular mechanisms for the ligand-exchange process are evaluated and implications for the anomalous fatty acid transport mechanism of LFABP are discussed. PMID:11969406

  4. NR4A orphan nuclear receptors influence retinoic acid and docosahexaenoic acid signaling via up-regulation of fatty acid binding protein 5

    Volakakis, Nikolaos; Joodmardi, Eliza [Ludwig Institute for Cancer Research Ltd., Box 240, S-17177 Stockholm (Sweden); Perlmann, Thomas, E-mail: thomas.perlmann@licr.ki.se [Ludwig Institute for Cancer Research Ltd., Box 240, S-17177 Stockholm (Sweden); The Department of Cell and Molecular Biology, Karolinska Institute, S-17177 Stockholm (Sweden)

    2009-12-25

    The orphan nuclear receptor (NR) Nurr1 is expressed in the developing and adult nervous system and is also induced as an immediate early gene in a variety of cell types. In silico analysis of human promoters identified fatty acid binding protein 5 (FABP5), a protein shown to enhance retinoic acid-mediated PPAR{beta}/{delta} signaling, as a potential Nurr1 target gene. Nurr1 has previously been implicated in retinoid signaling via its heterodimerization partner RXR. Since NRs are commonly involved in cross-regulatory control we decided to further investigate the regulatory relationship between Nurr1 and FABP5. FABP5 expression was up-regulated by Nurr1 and other NR4A NRs in HEK293 cells, and Nurr1 was shown to activate and bind to the FABP5 promoter, supporting that FABP5 is a direct downstream target of NR4A NRs. We also show that the RXR ligand docosahexaenoic acid (DHA) can induce nuclear translocation of FABP5. Moreover, via up-regulation of FABP5 Nurr1 can enhance retinoic acid-induced signaling of PPAR{beta}/{delta} and DHA-induced activation of RXR. We also found that other members of the NR4A orphan NRs can up-regulate FABP5. Thus, our findings suggest that NR4A orphan NRs can influence signaling events of other NRs via control of FABP5 expression levels.

  5. Clinical significance of urinary liver-type fatty acid binding protein at various stages of nephropathy.

    Viswanathan, V; Sivakumar, S; Sekar, V; Umapathy, D; Kumpatla, S

    2015-01-01

    This cross-sectional study was to evaluate the levels of urinary liver-type fatty acid binding protein (u-LFABP pg/mg urine creatinine ratio) at different stages of diabetic nephropathy and to see its correlation with other clinical parameters in South Indian patients with type 2 diabetes mellitus (T2DM). A total of 65 (M: F; 42:23) T2DM subjects were divided into three groups, and were compared with 13 (M: F; 3:10) nondiabetic controls. The study groups were as follows: normoalbuminuric (n = 22), microalbuminuric (n = 22) and macroalbuminuric (n = 21). Estimated glomerular filtration rate (eGFR) was calculated using Cockcroft and Gault formula. u-LFABP levels in spot urine samples were measured with a solid phase enzyme linked immunosorbent assay. This study showed that u-LFABP levels were undetectable in healthy controls and was very low in the normoalbuminuric subjects. Elevated levels of u-LFABP are evident from the microalbuminuric stage indicating tubular damage. The levels of u-LFABP increased gradually with declining renal function. Geometric mean (95% confidence interval) for normoalbuminuria was 0.65 (0.47-0.97), microalbuminuria was 0.99 (0.55-1.97) and macroalbuminuria was 5.16 (1.8-14.5), (P = 0.005). In conclusion, u-LFABP levels were elevated in patients with reduced eGFR and showed a positive correlation with systolic blood pressure and protein to creatinine ratio in the total study subjects. PMID:26628791

  6. Fatty acid binding proteins FABP9 and FABP10 participate in antibacterial responses in Chinese mitten crab, Eriocheir sinensis.

    Lin Cheng

    Full Text Available Invertebrates rely solely on the innate immune system for defense against pathogens and other stimuli. Fatty acid binding proteins (FABP, members of the lipid binding proteins superfamily, play a crucial role in fatty acid transport and lipid metabolism and are also involved in gene expression induced by fatty acids. In the vertebrate immune system, FABP is involved in inflammation regulated by fatty acids through its interaction with peroxidase proliferator activate receptors (PPARs. However, the immune functions of FABP in invertebrates are not well characterized. For this reason, we investigated the immune functionality of two fatty acid binding proteins, Es-FABP9 and Es-FABP10, following lipopolysaccharide (LPS challenge in the Chinese mitten crab (Eriocheir sinensis. An obvious variation in the expression of Es-FABP9 and Es-FABP10 mRNA in E. sinensis was observed in hepatopancreas, gills, and hemocytes post-LPS challenge. Recombinant proteins rEs-FABP9 and rEs-FABP10 exhibited distinct bacterial binding activity and bacterial agglutination activity against Escherichia coli and Staphylococcus aureus. Furthermore, bacterial growth inhibition assays demonstrated that rEs-FABP9 responds positively to the growth inhibition of Vibrio parahaemolyticuss and S. aureus, while rEs-FABP10 responds positively to the growth inhibition of Aeromonas hydrophila and Bacillus subtilis. Coating of agarose beads with recombinant rEs-FABP9 and rEs-FABP10 dramatically enhanced encapsulation of the beads by crab hemocytes in vitro. In conclusion, the data presented here demonstrate the participation of these two lipid metabolism-related proteins in the innate immune system of E. sinensis.

  7. Effects of fatty acids and growth hormone on liver fatty acid binding protein and PPARalpha in rat liver.

    Carlsson, L; Lindén, D; Jalouli, M; Oscarsson, J

    2001-10-01

    The aim of this study was to investigate the interaction between long-chain fatty acids (LCFA) and growth hormone (GH) in the regulation of liver fatty acid binding protein (LFABP) and peroxisome proliferator-activated receptor-alpha (PPARalpha). Cultured rat hepatocytes were given oleic acid (OA; 500 microM) and GH (100 ng/ml) for 3 days. LFABP mRNA increased 3.6-fold by GH and 5.7-fold by OA, and combined incubation with GH and OA increased LFABP mRNA 17.6-fold. PPARalpha mRNA was decreased 50% by GH, but OA had no effect. Hypophysectomized (Hx) female rats were treated with L-thyroxine, cortisol, GH, and dietary fat for 7 days. PPARalpha mRNA levels were three- to fourfold higher in Hx than in normal female rats. GH decreased PPARalpha mRNA 50% in Hx rats. Dietary triglycerides (10% corn oil) increased LFABP mRNA and cytosolic LFABP about twofold but had no effect on PPARalpha mRNA in Hx rats. GH and dietary triglycerides had an additive effect on LFABP expression. Dietary triglycerides increased mitochondrial hydroxymethylglutaryl-CoA synthase mRNA only in the presence of GH. The diet increased serum triglycerides in Hx rats, and GH treatment prevented this increase. Addition of cholesterol to the diet did not influence LFABP levels but mitigated increased hepatic triglyceride content. In summary, these studies show that GH regulates LFABP expression independently of PPARalpha. Moreover, GH has different effects on PPARalpha-responsive genes and does not counteract the effect of LCFA on the expression of these gene products. PMID:11551854

  8. Structural analysis of site-directed mutants of cellular retinoic acid-binding protein II addresses the relationship between structural integrity and ligand binding

    Vaezeslami, Soheila; Jia, Xiaofei; Vasileiou, Chrysoula; Borhan, Babak; Geiger, James H. (MSU); (Rigaku)

    2009-09-02

    The structural integrity of cellular retinoic acid-binding protein II (CRABPII) has been investigated using the crystal structures of CRABPII mutants. The overall fold was well maintained by these CRABPII mutants, each of which carried multiple different mutations. A water-mediated network is found to be present across the large binding cavity, extending from Arg111 deep inside the cavity to the {alpha} 2 helix at its entrance. This chain of interactions acts as a 'pillar' that maintains the integrity of the protein. The disruption of the water network upon loss of Arg111 leads to decreased structural integrity of the protein. A water-mediated network can be re-established by introducing the hydrophilic Glu121 inside the cavity, which results in a rigid protein with the {alpha}2 helix adopting an altered conformation compared with wild-type CRABPII.

  9. Nucleic acids encoding phloem small RNA-binding proteins and transgenic plants comprising them

    Lucas, William J.; Yoo, Byung-Chun; Lough, Tony J.; Varkonyi-Gasic, Erika

    2007-03-13

    The present invention provides a polynucleotide sequence encoding a component of the protein machinery involved in small RNA trafficking, Cucurbita maxima phloem small RNA-binding protein (CmPSRB 1), and the corresponding polypeptide sequence. The invention also provides genetic constructs and transgenic plants comprising the polynucleotide sequence encoding a phloem small RNA-binding protein to alter (e.g., prevent, reduce or elevate) non-cell autonomous signaling events in the plants involving small RNA metabolism. These signaling events are involved in a broad spectrum of plant physiological and biochemical processes, including, for example, systemic resistance to pathogens, responses to environmental stresses, e.g., heat, drought, salinity, and systemic gene silencing (e.g., viral infections).

  10. Nucleic acids encoding phloem small RNA-binding proteins and transgenic plants comprising them

    Lucas, William J.; Yoo, Byung-Chun; Lough, Tony J.; Varkonyi-Gasic, Erika

    2007-03-13

    The present invention provides a polynucleotide sequence encoding a component of the protein machinery involved in small RNA trafficking, Cucurbita maxima phloem small RNA-binding protein (CmPSRB 1), and the corresponding polypeptide sequence. The invention also provides genetic constructs and transgenic plants comprising the polynucleotide sequence encoding a phloem small RNA-binding protein to alter (e.g., prevent, reduce or elevate) non-cell autonomous signaling events in the plants involving small RNA metabolism. These signaling events are involved in a broad spectrum of plant physiological and biochemical processes, including, for example, systemic resistance to pathogens, responses to environmental stresses, e.g., heat, drought, salinity, and systemic gene silencing (e.g., viral infections).

  11. Fatty acid binding protein 4 deficiency protects against oxygen-induced retinopathy in mice.

    Magali Saint-Geniez

    Full Text Available Retinopathy of prematurity (ROP is a leading cause of blindness in children worldwide due to increasing survival rates of premature infants. Initial suppression, followed by increased production of the retinal vascular endothelial growth factor-A (VEGF expression are key events that trigger the pathological neovascularization in ROP. Fatty acid binding protein 4 (FABP4 is an intracellular lipid chaperone that is induced by VEGF in a subset of endothelial cells. FABP4 exhibits a pro-angiogenic function in cultured endothelial cells and in airway microvasculature, but whether it plays a role in modulation of retinal angiogenesis is not known. We hypothesized that FABP4 deficiency could ameliorate pathological retinal vascularization and investigated this hypothesis using a well-characterized mouse model of oxygen-induced retinopathy (OIR. We found that FABP4 was not expressed in retinal vessels, but was present in resident macrophages/microglial cells and endothelial cells of the hyaloid vasculature in the immature retina. While FABP4 expression was not required for normal development of retinal vessels, FABP4 expression was upregulated and localized to neovascular tufts in OIR. FABP4-/- mice demonstrated a significant decrease in neovessel formation as well as a significant improvement in physiological revascularization of the avascular retinal tissues. These alterations in retinal vasculature were accompanied by reduced endothelial cell proliferation, but no effect on apoptosis or macrophage/microglia recruitment. FABP4-/- OIR samples demonstrated decreased expression of genes involved in angiogenesis, such as Placental Growth Factor, and angiopoietin 2. Collectively, our findings suggest FABP4 as a potential target of pathologic retinal angiogenesis in proliferative retinopathies.

  12. Fatty acid binding protein 4 deficiency protects against oxygen-induced retinopathy in mice.

    Saint-Geniez, Magali; Ghelfi, Elisa; Liang, Xiaoliang; Yu, Chenwei; Spencer, Carrie; Abend, Stephanie; Hotamisligil, Gokhan; Cataltepe, Sule

    2014-01-01

    Retinopathy of prematurity (ROP) is a leading cause of blindness in children worldwide due to increasing survival rates of premature infants. Initial suppression, followed by increased production of the retinal vascular endothelial growth factor-A (VEGF) expression are key events that trigger the pathological neovascularization in ROP. Fatty acid binding protein 4 (FABP4) is an intracellular lipid chaperone that is induced by VEGF in a subset of endothelial cells. FABP4 exhibits a pro-angiogenic function in cultured endothelial cells and in airway microvasculature, but whether it plays a role in modulation of retinal angiogenesis is not known. We hypothesized that FABP4 deficiency could ameliorate pathological retinal vascularization and investigated this hypothesis using a well-characterized mouse model of oxygen-induced retinopathy (OIR). We found that FABP4 was not expressed in retinal vessels, but was present in resident macrophages/microglial cells and endothelial cells of the hyaloid vasculature in the immature retina. While FABP4 expression was not required for normal development of retinal vessels, FABP4 expression was upregulated and localized to neovascular tufts in OIR. FABP4-/- mice demonstrated a significant decrease in neovessel formation as well as a significant improvement in physiological revascularization of the avascular retinal tissues. These alterations in retinal vasculature were accompanied by reduced endothelial cell proliferation, but no effect on apoptosis or macrophage/microglia recruitment. FABP4-/- OIR samples demonstrated decreased expression of genes involved in angiogenesis, such as Placental Growth Factor, and angiopoietin 2. Collectively, our findings suggest FABP4 as a potential target of pathologic retinal angiogenesis in proliferative retinopathies. PMID:24802082

  13. STRUCTURAL AND FUNCTIONAL INTERACTION OF FATTY ACIDS WITH HUMAN LIVER FATTY ACID BINDING PROTEIN (L-FABP) T94A VARIANT

    Huang, Huan; McIntosh, Avery L.; Martin, Gregory G.; Landrock, Kerstin K.; Landrock, Danilo; Gupta, Shipra; Atshaves, Barbara P.; Kier, Ann B.; Schroeder, Friedhelm

    2014-01-01

    The human liver fatty acid binding protein (L-FABP) T94A variant, the most common in the FABP family, has been associated with elevated liver triglyceride (TG) levels. How this amino acid substitution elicits these effects is not known. This issue was addressed with human recombinant wild-type (WT, T94T) and T94A variant L-FABP proteins as well as cultured primary human hepatocytes expressing the respective proteins (genotyped as TT, TC, and CC). T94A substitution did not or only slightly alt...

  14. Backbone and sidechain 1H, 13C and 15N resonance assignments of the human brain-type fatty acid binding protein (FABP7) in its apo form and the holo forms binding to DHA, oleic acid, linoleic acid and elaidic acid

    Oeemig, Jesper S; Jørgensen, Mathilde L; Hansen, Mikka S;

    2009-01-01

    In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid.......In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid....

  15. Heart type fatty acid binding protein response and subsequent development of atherosclerosis in insulin resistant polycystic ovary syndrome patients

    Cakir Evrim; Ozbek Mustafa; Sahin Mustafa; Cakal Erman; Gungunes Askin; Ginis Zeynep; Demirci Taner; Delibasi Tuncay

    2012-01-01

    Abstract Background Women with polycystic ovary syndrome (PCOS) have higher risk for cardiovascular disease (CVD). Heart type fatty acid binding protein (HFABP) has been found to be predictive for myocardial ischemia.Wet ested whether HFABP is the predictor for CVD in PCOS patients, who have an increased risk of cardiovascular disease. Methods This was a prospective, cross sectional controlled study conducted in a training and research hospital.The study population consisted of 46 reproductiv...

  16. Analysis of the regulation of fatty acid binding protein 7 expression in human renal carcinoma cell lines

    Sugiyama Takayuki; Teratani Takumi; Takayama Tatsuya; Takaoka Naohisa; Mugiya Soichi; Ozono Seiichiro

    2011-01-01

    Abstract Background Improving the treatment of renal cell carcinoma (RCC) will depend on the development of better biomarkers for predicting disease progression and aiding the design of appropriate therapies. One such marker may be fatty acid binding protein 7 (FABP7), also known as B-FABP and BLBP, which is expressed normally in radial glial cells of the developing central nervous system and cells of the mammary gland. Melanomas, glioblastomas, and several types of carcinomas, including RCC,...

  17. Polyunsaturated Fatty Acids Selectively Suppress Sterol Regulatory Element-binding Protein-1 through Proteolytic Processing and Autoloop Regulatory Circuit*

    Takeuchi, Yoshinori; Yahagi, Naoya; Izumida, Yoshihiko; Nishi, Makiko; Kubota, Midori; Teraoka, Yuji; Yamamoto, Takashi; Matsuzaka, Takashi; Nakagawa, Yoshimi; Sekiya, Motohiro; Iizuka, Yoko; Ohashi, Ken; Osuga, Jun-ichi; Gotoda, Takanari; Ishibashi, Shun

    2010-01-01

    Sterol regulatory element-binding protein (SREBP)-1 is a key transcription factor for the regulation of lipogenic enzyme genes in the liver. Polyunsaturated fatty acids (PUFA) selectively suppress hepatic SREBP-1, but molecular mechanisms remain largely unknown. To gain insight into this regulation, we established in vivo reporter assays to assess the activities of Srebf1c transcription and proteolytic processing. Using these in vivo reporter assays, we showed that the primary mechanism for P...

  18. Elevation of urinary liver-type fatty acid binding protein after cardiac catheterization related to cardiovascular events

    Kamijo-Ikemori A; Hashimoto N; Sugaya T; Matsui K; Hisamichi M; Shibagaki Y; Miyake F; Kimura K

    2015-01-01

    Atsuko Kamijo-Ikemori,1,3 Nobuyuki Hashimoto,2 Takeshi Sugaya,1 Katsuomi Matsui,1 Mikako Hisamichi,1 Yugo Shibagaki,1 Fumihiko Miyake,2 Kenjiro Kimura1 1Department of Nephrology and Hypertension, 2Department of Cardiology, 3Department of Anatomy, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan Purpose: Contrast medium (CM) induces tubular hypoxia via endothelial damage due to direct cytotoxicity or viscosity. Urinary liver-type fatty acid binding protein (L-FABP) increas...

  19. Fluorescent n-3 and n-6 Very Long Chain Polyunsaturated Fatty Acids: THREE-PHOTON IMAGING IN LIVING CELLS EXPRESSING LIVER FATTY ACID-BINDING PROTEIN*

    McIntosh, Avery L.; Huang, Huan; Atshaves, Barbara P.; Wellberg, Elizabeth; Kuklev, Dmitry V.; Smith, William L.; Kier, Ann B.; Schroeder, Friedhelm

    2010-01-01

    Despite the considerable beneficial effects of n-3 and n-6 very long chain polyunsaturated fatty acids (VLC-PUFAs), very little is known about the factors that regulate their uptake and intracellular distribution in living cells. This issue was addressed in cells expressing liver-type fatty acid-binding protein (L-FABP) by real time multiphoton laser scanning microscopy of novel fluorescent VLC-PUFAs containing a conjugated tetraene fluorophore near the carboxyl group and natural methylene-in...

  20. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus.

    Rey-Burusco, M Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R; Roe, Andrew J; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W; Córsico, Betina; Smith, Brian O

    2015-11-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein-ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male. PMID:26318523

  1. Identification of the SNP (Single Nucleotide Polymorphism) for Fatty Acid Composition Associated with Beef Flavor-related FABP4 (Fatty Acid Binding Protein 4) in Korean Cattle

    Oh, Dong-yep; Lee, Yoon-Seok; La, Boo-mi; Yeo, Jung-Sou

    2012-01-01

    In this study, we investigated the relationship between unsaturated fatty acids influencing beef flavor and four types of SNPs (c.280A>G, c.388G>A, c.408G>C and c.456A>G) located at exon 2, 3 and 4 of the FABP4 gene, which is a fatty acid binding protein 4 in Korean cattle (n = 513). When analyzing the relationship between single genotype, fatty acids and carcass trait, individuals of GG, GG, CC and GG genotypes that are homozygotes, had a higher content of unsaturated fatty acids and marblin...

  2. Loss of Fatty Acid Binding Protein 4/aP2 Reduces Macrophage Inflammation Through Activation of SIRT3.

    Xu, Hongliang; Hertzel, Ann V; Steen, Kaylee A; Bernlohr, David A

    2016-03-01

    Activation of proinflammatory macrophages plays an important role in the pathogenesis of insulin resistance, type 2 diabetes, and atherosclerosis. Previous work using high fat-fed mice has shown that ablation of the adipocyte fatty acid binding protein (FABP4/aP2) in macrophages leads to an antiinflammatory state both in situ and in vivo, and the mechanism is linked, in part, to increased intracellular monounsaturated fatty acids and the up-regulation of uncoupling protein 2. Here, we show that loss of FABP4/aP2 in macrophages additionally induces sirtuin 3 (SIRT3) expression and that monounsaturated fatty acids (C16:1, C18:1) lead to increased SIRT3 protein expression. Increased expression of SirT3 in FABP4/aP2 null macrophages occurs at the protein level with no change in SirT3 mRNA. When compared with controls, silencing of SIRT3 in Raw246.7 macrophages leads to increased expression of inflammatory cytokines, inducible nitric oxide synthase and cyclooxygenase 2. In contrast, loss of SIRT3 in FABP4/aP2-deficient macrophages attenuates the suppressed inflammatory signaling, reduced reactive oxygen species production, lipopolysaccharide-induced mitochondrial dysfunction, and increased fatty acid oxidation. These results suggest that the antiinflammatory phenotype of FABP4/aP2 null mice is mediated by increased intracellular monounsaturated fatty acids leading to the increased expression of both uncoupling protein 2 and SirT3. PMID:26789108

  3. Effects of macromolecular crowding on a small lipid binding protein probed at the single-amino acid level.

    Pérez Santero, Silvia; Favretto, Filippo; Zanzoni, Serena; Chignola, Roberto; Assfalg, Michael; D'Onofrio, Mariapina

    2016-09-15

    Macromolecular crowding is a distinctive feature of the cellular interior, influencing the behaviour of biomacromolecules. Despite significant advancements in the description of the effects of crowding on global protein properties, the influence of cellular components on local protein attributes has received limited attention. Here, we describe a residue-level systematic interrogation of the structural, dynamic, and binding properties of the liver fatty acid binding protein (LFABP) in crowded solutions. Two-dimensional NMR spectral fingerprints and relaxation data were collected on LFABP in the presence of polymeric and biomolecular crowders. Non-interacting crowders produced minimal site-specific spectral perturbations on ligand-free and lipid-bound LFABP. Conformational adaptations upon ligand binding reproduced those observed in dilute solution, but a perturbation of the free oleate state resulted in less favorable uptake. When LFABP engaged in direct interactions with background molecules, changes in local chemical environments were detected for residues of the internal binding pocket and of the external surface. Enhanced complexity was introduced by investigating LFABP in cell lysates, and in membrane-bounded compartments. LFABP was able to capture ligands from prokaryotic and eukaryotic cell lysates, and from artificial cells (water-in-oil emulsion droplets). The data suggest that promiscuous interactions are a major factor influencing protein function in the cell. PMID:27457417

  4. High Dietary Fat Exacerbates Weight Gain and Obesity in Female Liver Fatty Acid Binding Protein Gene-Ablated Mice

    Atshaves, Barbara P.; McIntosh, Avery L.; Storey, Stephen M.; Landrock, Kerstin K.; Kier, Ann B.; Schroeder, Friedhelm

    2009-01-01

    Since liver fatty acid binding protein (L-FABP) facilitates uptake/oxidation of long-chain fatty acids in cultured transfected cells and primary hepatocytes, loss of L-FABP was expected to exacerbate weight gain and/or obesity in response to high dietary fat. Male and female wild-type (WT) and L-FABP gene-ablated mice, pair-fed a defined isocaloric control or high fat diet for 12 weeks, consumed equal amounts of food by weight and kcal. Male WT mice gained weight faster than their female WT c...

  5. Liver Fatty Acid Binding Protein Gene-ablation Exacerbates Weight Gain in High-Fat Fed Female Mice

    McIntosh, Avery L.; Atshaves, Barbara P.; Landrock, Danilo; Landrock, Kerstin K.; Martin, Gregory G.; Storey, Stephen M.; Kier, Ann B.; Schroeder, Friedhelm

    2013-01-01

    Loss of liver fatty acid binding protein (L-FABP) decreases long chain fatty acid uptake and oxidation in primary hepatocytes and in vivo. On this basis, L-FABP gene ablation would potentiate high-fat diet-induced weight gain and weight gain/energy intake. While this was indeed the case when L-FABP null (−/−) mice on the C57BL/6NCr background were pair-fed high fat diet, whether this would also be observed under high-fat diet fed ad libitum was not known. Therefore, this possibility was exami...

  6. Useable diffraction data from a multiple microdomain-containing crystal of Ascaris suum As-p18 fatty-acid-binding protein using a microfocus beamline

    As-p18, an unusual fatty-acid-binding protein from a parasitic nematode, was expressed in bacteria, purified and crystallized. The use of a microfocus beamline was essential for data collection. As-p18 is a fatty-acid-binding protein from the parasitic nematode Ascaris suum. Although it exhibits sequence similarity to mammalian intracellular fatty-acid-binding proteins, it contains features that are unique to nematodes. Crystals were obtained, but initial diffraction data analysis revealed that they were composed of a number of ‘microdomains’. Interpretable data could only be collected using a microfocus beamline with a beam size of 12 × 8 µm

  7. Plasma membrane fatty acid-binding protein and mitochondrial glutamic-oxaloacetic transaminase of rat liver are related

    The hepatic plasma membrane fatty acid-binding protein (h-FABPPM) and the mitochondrial isoenzyme of glutamic-oxaloacetic transaminase (mGOT) of rat liver have similar amino acid compositions and identical amino acid sequences for residues 3-24. Both proteins migrate with an apparent molecular mass of 43 kDa on SDS/polyacrylamide gel electrophoresis, have a similar pattern of basic charge isomers on isoelectric focusing, are eluted similarly from four different high-performance liquid chromatographic columns, have absorption maxima at 435 nm under acid conditions and 354 nm at pH 8.3, and bind oleate. Sinusoidally enriched liver plasma membranes and purified h-FABPPM have GOT enzymatic activity. Monospecific rabbit antiserum against h-FABPPM reacts on Western blotting with mGOT, and vice versa. Antisera against both proteins produce plasma membrane immunofluorescence in rat hepatocytes and selectively inhibit the hepatocellular uptake of [3H]oleate but not that of [35S]sulfobromophthalein or [14C]taurocholate. The inhibition of oleate uptake produced by anti-h-FABPPM can be eliminated by preincubation of the antiserum with mGOT; similarly, the plasma membrane immunofluorescence produced by either antiserum can be eliminated by preincubation with the other antigen. These data suggest that h-FABPPM and mGOT are closely related

  8. Serum high-sensitivity C-reaction protein and heart fatty acid binding protein level and cardiac accidents in patients with unstable angina pectoris

    朱红秋

    2006-01-01

    Objective To investigate the relationship between serum high-sensitivity C-reaction protein (hs-CRP) and heart fatty acid binding protein (h-FABP) on cardiac accidents in patients with unstable angina pectoris (UAP). Methods Serum levels of hs-CRP, h-FABP, cardiac troponin-Ⅰ(cTn-Ⅰ) and creatine kinase MB isoenzyme (CK-MB) were measured and cardiac accidents within 2 weeks after the test were observed in 74 patients (male

  9. Fatty acid binding protein 4 is a target of VEGF and a regulator of cell proliferation in endothelial cells

    Elmasri, Harun; Karaaslan, Cagatay; Teper, Yaroslav; Ghelfi, Elisa; Weng, Meiqian; Ince, Tan A.; Kozakewich, Harry; Bischoff, Joyce; Cataltepe, Sule

    2009-01-01

    Fatty acid binding protein 4 (FABP4) plays an important role in maintaining glucose and lipid homeostasis. FABP4 has been primarily regarded as an adipocyte- and macrophage-specific protein, but recent studies suggest that it may be more widely expressed. We found strong FABP4 expression in the endothelial cells (ECs) of capillaries and small veins in several mouse and human tissues, including the heart and kidney. FABP4 was also detected in the ECs of mature human placental vessels and infan...

  10. The alpha-helical domain of liver fatty acid binding protein is responsible for the diffusion-mediated transfer of fatty acids to phospholipid membranes.

    Córsico, Betina; Liou, Heng Ling; Storch, Judith

    2004-03-30

    Intestinal fatty acid binding protein (IFABP) and liver FABP (LFABP), homologous proteins expressed at high levels in intestinal absorptive cells, employ markedly different mechanisms for the transfer of fatty acids (FAs) to acceptor membranes. Transfer from IFABP occurs during protein-membrane collisional interactions, while for LFABP, transfer occurs by diffusion through the aqueous phase. Earlier, we had shown that the helical domain of IFABP is critical in determining its collisional FA transfer mechanism. In the study presented here, we have engineered a pair of chimeric proteins, one with the "body" (ligand binding domain) of IFABP and the alpha-helical region of LFABP (alphaLbetaIFABP) and the other with the ligand binding pocket of LFABP and the helical domain of IFABP (alphaIbetaLFABP). The objective of this work was to determine whether the change in the alpha-helical domain of each FABP would alter the rate and mechanism of transfer of FA from the chimeric proteins in comparison with those of the wild-type proteins. The fatty acid transfer properties of the FABP chimeras were examined using a fluorescence resonance transfer assay. The results showed a significant modification of the absolute rate of FA transfer from the chimeric proteins compared to that of the wild type, indicating that the slower rate of FA transfer observed for wild-type LFABP relative to that of wild-type IFABP is, in part, determined by the helical domain of the proteins. In addition to these quantitative changes, it was of great interest to observe that the apparent mechanism of FA transfer also changed when the alpha-helical domain was exchanged, with transfer from alphaLbetaIFABP occurring by aqueous diffusion and transfer from alphaIbetaLFABP occurring via protein-membrane collisional interactions. These results demonstrate that the alpha-helical region of LFABP is responsible for its diffusional mechanism of fatty acid transfer to membranes. PMID:15035630

  11. Urinary excretion of fatty acid-binding protein 4 is associated with albuminuria and renal dysfunction.

    Yusuke Okazaki

    Full Text Available Fatty acid-binding protein 4 (FABP4/A-FABP/aP2 is expressed in not only adipocytes and macrophages but also peritubular capillaries in the normal kidney. We recently demonstrated that ectopic expression of FABP4, but not FABP1 known as liver FABP (L-FABP, in the glomerulus is associated with progression of proteinuria and renal dysfunction. However, urinary excretion of FABP4 has not been investigated.Subjects who participated in the Tanno-Sobetsu Study, a study with a population-based cohort design, in 2011 (n = 392, male/female: 166/226 were enrolled. Urinary FABP4 (U-FABP4 and urinary albumin-to-creatinine ratio (UACR were measured. Change in estimated glomerular filtration rate (eGFR was followed up one year later.In 93 (23.7% of the 392 subjects, U-FABP4 level was below the sensitivity of the assay. Subjects with undetectable U-FABP4 were younger and had lower UACR and higher eGFR levels than subjects with measurable U-FABP4. U-FABP4 level was positively correlated with age, systolic blood pressure and levels of serum FABP4 (S-FABP4, triglycerides, hemoglobin A1c (HbA1c, urinary FABP1 (U-FABP1 and UACR (r = 0.360, p<0.001. Age, S-FABP4, U-FABP1 and UACR were independent predictors of U-FABP4. On the other hand, systolic blood pressure, HbA1c and U-FABP4 were independently correlated with UACR. Reduction in eGFR after one year was significantly larger in a group with the highest tertile of baseline U-FABP4 than a group with the lowest tertile.Urinary FABP4 level is independently correlated with level of albuminuria and possibly predicts yearly decline of eGFR. U-FABP4 would be a novel biomarker of glomerular damage.

  12. Purification and characterisation of a glutamic acid-containing peptide with calcium-binding capacity from whey protein hydrolysate.

    Huang, Shun-Li; Zhao, Li-Na; Cai, Xixi; Wang, Shao-Yun; Huang, Yi-Fan; Hong, Jing; Rao, Ping-Fan

    2015-02-01

    The bioavailability of dietary ionised calcium is affected by intestinal basic environment. Calcium-binding peptides can form complexes with calcium to improve its absorption and bioavailability. The aim of this study was focused on isolation and characterisation of a calcium-binding peptide from whey protein hydrolysates. Whey protein was hydrolysed using Flavourzyme and Protamex with substrate to enzyme ratio of 25:1 (w/w) at 49 °C for 7 h. The calcium-binding peptide was isolated by DEAE anion-exchange chromatography, Sephadex G-25 gel filtration and reversed phase high-performance liquid chromatography (RP-HPLC). A purified peptide of molecular mass 204 Da with strong calcium binding ability was identified on chromatography/electrospray ionisation (LC/ESI) tandem mass spectrum to be Glu-Gly (EG) after analysis and alignment in database. The calcium binding capacity of EG reached 67·81 μg/mg, and the amount increased by 95% compared with whey protein hydrolysate complex. The UV and infrared spectrometer analysis demonstrated that the principal sites of calcium-binding corresponded to the carboxyl groups and carbonyl groups of glutamic acid. In addition, the amino group and peptide amino are also the related groups in the interaction between EG and calcium ion. Meanwhile, the sequestered calcium percentage experiment has proved that EG-Ca is significantly more stable than CaCl2 in human gastrointestinal tract in vitro. The findings suggest that the purified dipeptide has the potential to be used as ion-binding ingredient in dietary supplements. PMID:25592629

  13. Investigating the linkage between disease-causing amino acid variants and their effect on protein stability and binding.

    Peng, Yunhui; Alexov, Emil

    2016-02-01

    Single amino acid variations (SAV) occurring in human population result in natural differences between individuals or cause diseases. It is well understood that the molecular effect of SAV can be manifested as changes of the wild type characteristics of the corresponding protein, among which are the protein stability and protein interactions. Typically the effect of SAV on protein stability and interactions was assessed via the changes of the wild type folding and binding free energies. However, in terms of SAV affecting protein functionally and disease susceptibility, one wants to know to what extend the wild type function is perturbed by the SAV. Here it is demonstrated that relative, rather than the absolute, change of the folding and binding free energy serves as a good indicator for SAV association with disease. Using HumVar as a source for disease-causing SAV and experimentally determined free energy changes from ProTherm and SKEMPI databases, correlation coefficients (CC) between the disease index (Pd) and relative folding (Ppr,f) and binding (Ppr,b) probability indexes, respectively, was achieved. The obtained CCs demonstrated the applicability of the proposed approach and it served as good indicator for SAV association with disease. PMID:26650512

  14. Fatty Acid-binding Proteins Interact with Comparative Gene Identification-58 Linking Lipolysis with Lipid Ligand Shuttling.

    Hofer, Peter; Boeszoermenyi, Andras; Jaeger, Doris; Feiler, Ursula; Arthanari, Haribabu; Mayer, Nicole; Zehender, Fabian; Rechberger, Gerald; Oberer, Monika; Zimmermann, Robert; Lass, Achim; Haemmerle, Guenter; Breinbauer, Rolf; Zechner, Rudolf; Preiss-Landl, Karina

    2015-07-24

    The coordinated breakdown of intracellular triglyceride (TG) stores requires the exquisitely regulated interaction of lipolytic enzymes with regulatory, accessory, and scaffolding proteins. Together they form a dynamic multiprotein network designated as the "lipolysome." Adipose triglyceride lipase (Atgl) catalyzes the initiating step of TG hydrolysis and requires comparative gene identification-58 (Cgi-58) as a potent activator of enzyme activity. Here, we identify adipocyte-type fatty acid-binding protein (A-Fabp) and other members of the fatty acid-binding protein (Fabp) family as interaction partners of Cgi-58. Co-immunoprecipitation, microscale thermophoresis, and solid phase assays proved direct protein/protein interaction between A-Fabp and Cgi-58. Using nuclear magnetic resonance titration experiments and site-directed mutagenesis, we located a potential contact region on A-Fabp. In functional terms, A-Fabp stimulates Atgl-catalyzed TG hydrolysis in a Cgi-58-dependent manner. Additionally, transcriptional transactivation assays with a luciferase reporter system revealed that Fabps enhance the ability of Atgl/Cgi-58-mediated lipolysis to induce the activity of peroxisome proliferator-activated receptors. Our studies identify Fabps as crucial structural and functional components of the lipolysome. PMID:25953897

  15. Intrinsic Nucleic Acid Dynamics Modulates HIV-1 Nucleocapsid Protein Binding to Its Targets

    Bazzi, Ali; Zargarian, Loussiné; Chaminade, Françoise; De Rocquigny, Hugues; René, Brigitte; Mély, Yves; Fossé, Philippe; Mauffret, Olivier

    2012-01-01

    HIV-1 nucleocapsid protein (NC) is involved in the rearrangement of nucleic acids occurring in key steps of reverse transcription. The protein, through its two zinc fingers, interacts preferentially with unpaired guanines in single-stranded sequences. In mini-cTAR stem-loop, which corresponds to the top half of the cDNA copy of the transactivation response element of the HIV-1 genome, NC was found to exhibit a clear preference for the TGG sequence at the bottom of mini-cTAR stem. To further u...

  16. Direct interaction between EgFABP1, a fatty acid binding protein from Echinococcus granulosus, and phospholipid membranes.

    Jorge L Porfido

    Full Text Available BACKGROUND: Growth and maintenance of hydatid cysts produced by Echinococcus granulosus have a high requirement for host lipids for biosynthetic processes, membrane building and possibly cellular and developmental signalling. This requires a high degree of lipid trafficking facilitated by lipid transporter proteins. Members of the fatty acid binding protein (FABP family have been identified in Echinococcus granulosus, one of which, EgFABP1 is expressed at the tegumental level in the protoscoleces, but it has also been described in both hydatid cyst fluid and secretions of protoscoleces. In spite of a considerable amount of structural and biophysical information on the FABPs in general, their specific functions remain mysterious. METHODOLOGY/PRINCIPAL FINDINGS: We have investigated the way in which EgFABP1 may interact with membranes using a variety of fluorescence-based techniques and artificial small unilamellar vesicles. We first found that bacterial recombinant EgFABP1 is loaded with fatty acids from the synthesising bacteria, and that fatty acid binding increases its resistance to proteinases, possibly due to subtle conformational changes induced on EgFABP1. By manipulating the composition of lipid vesicles and the ionic environment, we found that EgFABP1 interacts with membranes in a direct contact, collisional, manner to exchange ligand, involving both ionic and hydrophobic interactions. Moreover, we observed that the protein can compete with cytochrome c for association with the surface of small unilamellar vesicles (SUVs. CONCLUSIONS/SIGNIFICANCE: This work constitutes a first approach to the understanding of protein-membrane interactions of EgFABP1. The results suggest that this protein may be actively involved in the exchange and transport of fatty acids between different membranes and cellular compartments within the parasite.

  17. Visualization of Iron-Binding Micelles in Acidic Recombinant Biomineralization Protein, MamC

    Sanjay Kashyap; Taylor Woehl; Carmen Valverde-Tercedor; Miguel Sánchez-Quesada; Concepción Jiménez López; Tanya Prozorov

    2014-01-01

    Biological macromolecules are utilized in low-temperature synthetic methods to exert precise control over nanoparticle nucleation and placement. They enable low-temperature formation of a variety of functional nanostructured materials with properties often not achieved via conventional synthetic techniques. Here we report on the in situ visualization of a novel acidic bacterial recombinant protein, MamC, commonly present in the magnetosome membrane of several magnetotactic bacteria, including...

  18. Solution-state molecular structure of apo and oleate-liganded liver fatty acid-binding protein.

    He, Yan; Yang, Xiaomin; Wang, Hsin; Estephan, Rima; Francis, Fouad; Kodukula, Sarala; Storch, Judith; Stark, Ruth E

    2007-11-01

    Rat liver fatty acid-binding protein (LFABP) is distinctive among intracellular lipid-binding proteins (iLBPs): more than one molecule of long-chain fatty acid and a variety of diverse ligands can be bound within its large cavity, and in vitro lipid transfer to model membranes follows a mechanism that is diffusion-controlled rather than mediated by protein-membrane collisions. Because the apoprotein has proven resistant to crystallization, nuclear magnetic resonance spectroscopy offers a unique route to functionally informative comparisons of molecular structure and dynamics for LFABP in free (apo) and liganded (holo) forms. We report herein the solution-state structures determined for apo-LFABP at pH 6.0 and for holoprotein liganded to two oleates at pH 7.0, as well as the structure of the complex including locations of the ligands. 1H, 13C, and 15N resonance assignments revealed very similar types and locations of secondary structural elements for apo- and holo-LFABP as judged from chemical shift indices. The solution-state tertiary structures of the proteins were derived with the CNS/ARIA computational protocol, using distance and angular restraints based on 1H-1H nuclear Overhauser effects (NOEs), hydrogen-bonding networks, 3J(HNHA) coupling constants, intermolecular NOEs, and residual dipolar (NH) couplings. The holo-LFABP solution-state conformation is in substantial agreement with a previously reported X-ray structure [Thompson, J., Winter, N., Terwey, D., Bratt, J., and Banaszak, L. (1997) The crystal structure of the liver fatty acid-binding protein. A complex with two bound oleates, J. Biol. Chem. 272, 7140-7150], including the typical beta-barrel capped by a helix-turn-helix portal. In the solution state, the internally bound oleate has the expected U-shaped conformation and is tethered electrostatically, but the extended portal ligand can adopt a range of conformations based on the computationally refined structures, in contrast to the single

  19. Different functions of intestinal and liver-type fatty acid-binding proteins in intestine and in whole body energy homeostasis

    Lagakos, William Stacy; Gajda, Angela Marie; Agellon, Luis; Binas, Bert; Choi, Victor; Mandap, Bernadette; Russnak, Timothy; Zhou, Yin Xiu; Storch, Judith

    2011-01-01

    It has long been known that mammalian enterocytes coexpress two members of the fatty acid-binding protein (FABP) family, the intestinal FABP (IFABP) and the liver FABP (LFABP). Both bind long-chain fatty acids and have similar though not identical distributions in the intestinal tract. While a number of in vitro properties suggest the potential for different functions, the underlying reasons for expression of both proteins in the same cells are not known. Utilizing mice genetically lacking ei...

  20. Retinoid-binding proteins: similar protein architectures bind similar ligands via completely different ways.

    Yu-Ru Zhang

    Full Text Available BACKGROUND: Retinoids are a class of compounds that are chemically related to vitamin A, which is an essential nutrient that plays a key role in vision, cell growth and differentiation. In vivo, retinoids must bind with specific proteins to perform their necessary functions. Plasma retinol-binding protein (RBP and epididymal retinoic acid binding protein (ERABP carry retinoids in bodily fluids, while cellular retinol-binding proteins (CRBPs and cellular retinoic acid-binding proteins (CRABPs carry retinoids within cells. Interestingly, although all of these transport proteins possess similar structures, the modes of binding for the different retinoid ligands with their carrier proteins are different. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we analyzed the various retinoid transport mechanisms using structure and sequence comparisons, binding site analyses and molecular dynamics simulations. Our results show that in the same family of proteins and subcellular location, the orientation of a retinoid molecule within a binding protein is same, whereas when different families of proteins are considered, the orientation of the bound retinoid is completely different. In addition, none of the amino acid residues involved in ligand binding is conserved between the transport proteins. However, for each specific binding protein, the amino acids involved in the ligand binding are conserved. The results of this study allow us to propose a possible transport model for retinoids. CONCLUSIONS/SIGNIFICANCE: Our results reveal the differences in the binding modes between the different retinoid-binding proteins.

  1. CLINICAL EXPERIENCE OF CANCER IMMUNOTHERAPY INTEGRATED WITH OLEIC ACID COMPLEXED WITH DE-GLYCOSYLATED VITAMIN D BINDING PROTEIN

    Emma Ward

    2014-01-01

    Full Text Available Proteins highly represented in milk such as α-lactalbumin and lactoferrin bind Oleic Acid (OA to form complexes with selective anti-tumor activity. A protein present in milk, colostrum and blood, vitamin D binding protein is the precursor of a potent Macrophage Activating Factor (GcMAF and in analogy with other OA-protein complexes, we proposed that OA-GcMAF could demonstrate a greater immunotherapeutic activity than that of GcMAF alone. We describe a preliminary experience treating patients with advanced cancers, often labelled as “incurable” with an integrative immunotherapy centred on OA-GcMAF. Patients with advanced cancer were treated at the Immuno Biotech Treatment Centre with OA-GcMAF-based integrative immunotherapy in combination with a very low carbohydrate, high protein diet, fermented milk products containing naturally produced GcMAF, vitamin D3 and low-dose acetylsalicylic acid. When the primary tumor or a metastasis could be measured by ultrasonographic techniques, we observed, on average, a decrease of tumor volume of approximately 25% in a week. We also observed a consistent increase in splenic blood flow that was interpreted in the context of generalised immune system activation and allowed to assess the degree of responsiveness of the individual patient. The results reported here are consistent with the results previously described in the experimental animal harbouring a human hepatocellular carcinoma as well as with the results reported for neoadjuvant chemotherapy. OA-protein complexes are bound to play a leading role in cancer therapy thanks to selectivity of antitumoral effects, absence of any side effects, safety and oral availability. We hypothesise that OA-GcMAF, combines the known anticancer effects OA-protein complexes with the well established immune stimulating effects of GcMAF.

  2. Synthesis of recA protein and induction of bacteriophage lambda in single-strand deoxyribonucleic acid-binding protein mutants of Escherichia coli.

    Baluch, J; Chase, J W; Sussman, R

    1980-01-01

    We investigated the capacity of Escherichia coli mutants defective in the single-strand deoxyribonucleic acid (DNA)-binding protein to amplify the synthesis of the recA protein, induce prophage lambda, and degrade their DNA after treatment with ultraviolet radiation, mitomycin C, or bleomycin. The thermosensitive ssbA1 strain induced recA protein and lambda phage normally at 30 degrees C, but no induction was observed at 42 degrees C when ultraviolet radiation or mitomycin C was used. The lex...

  3. Fatty acid-binding protein 4 impairs the insulin-dependent nitric oxide pathway in vascular endothelial cells

    Aragonès Gemma; Saavedra Paula; Heras Mercedes; Cabré Anna; Girona Josefa; Masana Lluís

    2012-01-01

    Abstract Background Recent studies have shown that fatty acid-binding protein 4 (FABP4) plasma levels are associated with impaired endothelial function in type 2 diabetes (T2D). In this work, we analysed the effect of FABP4 on the insulin-mediated nitric oxide (NO) production by endothelial cells in vitro. Methods In human umbilical vascular endothelial cells (HUVECs), we measured the effects of FABP4 on the insulin-mediated endothelial nitric oxide synthase (eNOS) expression and activation a...

  4. Liver Fatty Acid Binding Protein Gene-Ablated Female Mice Exhibit Increased Age-Dependent Obesity123

    Martin, Gregory G.; Atshaves, Barbara P.; McIntosh, Avery L.; Mackie, John T.; Kier, Ann B.; Schroeder, Friedhelm

    2008-01-01

    Previous work done in our laboratory suggested a role for liver fatty acid binding protein (L-FABP) in obesity that develops in aging female L-FABP gene-ablated (−/−) mice. To examine this possibility in more detail, cohorts of wild-type (+/+) and L-FABP (−/−) female mice were fed a standard low-fat nonpurified rodent diet for up to 18 mo. Various obesity-related parameters were examined including body weight and fat and lean tissue mass. Obesity in (−/−) mice was associated with increased ex...

  5. Urinary Liver-Type Fatty Acid-Binding Protein Predicts Progression to Nephropathy in Type 1 Diabetic Patients

    Nielsen, Stine Elkjaer; Sugaya, Takeshi; Hovind, Peter; Baba, Tsuneharu; Parving, Hans-Henrik; Rossing, Peter

    2010-01-01

    OBJECTIVE Urinary liver-type fatty acid-binding protein (u-LFABP) is a marker of tubulointerstitial inflammation and has been shown to be increased in patients with type 1 diabetes and is further increased in patients who progress to micro- and macroalbuminuria. Our aim was to evaluate u-LFABP as a predictor of progression to micro- and macroalbuminuria in type 1 diabetes. RESEARCH DESIGN AND METHODS From an inception cohort of 277 patients, u-LFABP, adjusted for urinary creatinine (enzyme-li...

  6. Monitoring of Urinary L-Type Fatty Acid-Binding Protein Predicts Histological Severity of Acute Kidney Injury

    Negishi, Kousuke; Noiri, Eisei; DOI, Kent; Maeda-Mamiya, Rui; Sugaya, Takeshi; Portilla, Didier; Fujita, Toshiro

    2009-01-01

    The present study aimed to evaluate whether levels of urinary L-type fatty acid-binding protein (L-FABP) could be used to monitor histological injury in acute kidney injury (AKI) induced by cis-platinum (CP) injection and ischemia reperfusion (IR). Different degrees of AKI severity were induced by several renal insults (CP dose and ischemia time) in human L-FABP transgenic mice. Renal histological injury scores increased with both CP dose and ischemic time. In CP-induced AKI, urinary L-FABP l...

  7. The acid-labile subunit of human ternary insulin-like growth factor binding protein complex in serum

    Juul, A; Møller, S; Mosfeldt-Laursen, E; Rasmussen, M H; Scheike, Thomas Harder; Pedersen, S A; Kastrup, K W; Yu, Hao; Mistry, J; Rasmussen, S; Müller, J; Henriksen, J; Skakkebaek, N E

    1998-01-01

    not measurable by this approach or, alternatively, that the liver is not the primary source of circulating ALS, IGF-I, or IGFBP-3 in humans. In conclusion, we have provided extensive normal data for a novel ALS assay and found that circulating ALS levels exhibit minor diurnal variation. We suggest......Circulating insulin-like growth factor-I (IGF-I) is predominantly bound in the trimeric complex comprised of IGF binding protein-3 (IGFBP-3) and acid-labile subunit (ALS). Circulating concentrations of IGF-I, IGFBP-3 and ALS are believed to reflect the GH secretory status, but the clinical use of...

  8. Proteomic Upregulation of Fatty Acid Synthase and Fatty Acid Binding Protein 5 and Identification of Cancer- and Race-Specific Pathway Associations in Human Prostate Cancer Tissues

    Myers, Jennifer S.; von Lersner, Ariana K.; Sang, Qing-Xiang Amy

    2016-01-01

    Protein profiling studies of prostate cancer have been widely used to characterize molecular differences between diseased and non-diseased tissues. When combined with pathway analysis, profiling approaches are able to identify molecular mechanisms of prostate cancer, group patients by cancer subtype, and predict prognosis. This strategy can also be implemented to study prostate cancer in very specific populations, such as African Americans who have higher rates of prostate cancer incidence and mortality than other racial groups in the United States. In this study, age-, stage-, and Gleason score-matched prostate tumor specimen from African American and Caucasian American men, along with non-malignant adjacent prostate tissue from these same patients, were compared. Protein expression changes and altered pathway associations were identified in prostate cancer generally and in African American prostate cancer specifically. In comparing tumor to non-malignant samples, 45 proteins were significantly cancer-associated and 3 proteins were significantly downregulated in tumor samples. Notably, fatty acid synthase (FASN) and epidermal fatty acid-binding protein (FABP5) were upregulated in human prostate cancer tissues, consistent with their known functions in prostate cancer progression. Aldehyde dehydrogenase family 1 member A3 (ALDH1A3) was also upregulated in tumor samples. The Metastasis Associated Protein 3 (MTA3) pathway was significantly enriched in tumor samples compared to non-malignant samples. While the current experiment was unable to detect statistically significant differences in protein expression between African American and Caucasian American samples, differences in overrepresentation and pathway enrichment were found. Structural components (Cytoskeletal Proteins and Extracellular Matrix Protein protein classes, and Biological Adhesion Gene Ontology (GO) annotation) were overrepresented in African American but not Caucasian American tumors. Additionally, 5

  9. CCAAT/enhancer binding proteins alpha and epsilon cooperate with all-trans retinoic acid in therapy but differ in their antileukemic activities

    Lee, Young-jin; Jones, Letetia C.; Timchenko, Nikolai A.; Perrotti, Danilo; Tenen, Daniel G; Kogan, Scott C.

    2006-01-01

    CCAAT/enhancer binding proteins (C/EBPs) play critical roles in myelopoiesis. Dysregulation of these proteins likely contributes to the pathogenesis of myeloid disorders characterized by a block in granulopoiesis. In one such disease, acute promyelocytic leukemia (APL), a promyelocytic leukemia–retinoic acid receptor α (PML-RARα) fusion protein is expressed as a result of a t(15;17) chromosomal translocation. Treatment of PML-RARα leukemic cells with all-trans retinoic acid (ATRA) causes them...

  10. Heart type fatty acid binding protein response and subsequent development of atherosclerosis in insulin resistant polycystic ovary syndrome patients

    Cakir Evrim

    2012-12-01

    Full Text Available Abstract Background Women with polycystic ovary syndrome (PCOS have higher risk for cardiovascular disease (CVD. Heart type fatty acid binding protein (HFABP has been found to be predictive for myocardial ischemia.Wet ested whether HFABP is the predictor for CVD in PCOS patients, who have an increased risk of cardiovascular disease. Methods This was a prospective, cross sectional controlled study conducted in a training and research hospital.The study population consisted of 46 reproductive-age PCOS women and 28 control subjects. We evaluated anthropometric and metabolic parameters, carotid intima media thickness and HFABP levels in both PCOS patients and control group. Results Mean fasting insulin, homeostasis model assessment insulin resistance index (HOMA-IR, triglyceride, total cholesterol, low density lipoprotein cholesterol, free testosterone, total testosterone, carotid intima media thickness (CIMT levels were significantly higher in PCOS patients. Although HFABP levels were higher in PCOS patients, the difference did not reach statistically significant in early age groups. After adjustment for age and body mass index, HFABP level was positive correlated with hsCRP, free testosterone levels, CIMT and HOMA-IR. Conclusions Heart type free fatty acid binding protein appeared to have an important role in metabolic response and subsequent development of atherosclerosis in insulin resistant, hyperandrogenemic PCOS patients.

  11. Nucleic acid binding properties and intermediates of HCV core protein multimerization in Pichia pastoris

    Little is known about the in vivo assembly pathway or structure of the hepatitis C virus nucleocapsid. In this work the intermediates of HCcAg multimerization in Pichia pastoris cells and the nucleic acid binding properties of structured nucleocapsid-like particles (NLPs) were studied. Extensive cross-linking was observed for HCcAg after glutaraldehyde treatment. Data suggest that HCcAg exists in dimeric forms probably representing P21-P21, P21-P23, and P23-P23 dimers. In addition, the presence of HCcAg species that might represent trimers and multimers was observed. After sucrose equilibrium density gradient purification and nuclease digestion, NLPs were shown to contain both RNA and DNA molecules. Finally, the analysis by electron microscopy indicated that native NLPs were resistant to nuclease treatment. These results indicated that HCcAg assembles through dimers, trimers, and multimers' intermediates into capsids in P. pastoris cells. Assembly of NLPs in its natural environment might confer stability to these particles by adopting a compact structure

  12. Molecular characterization, tissue expression, and polymorphism analysis of liver-type fatty acid binding protein in Landes geese.

    Song, Z; Shao, D; Sun, X X; Niu, J W; Gong, D Q

    2015-01-01

    Liver weight is an important economic trait in the fatty goose liver industry. Liver-type fatty acid binding protein (L-FABP) is involved in the formation and metabolism of fatty acids. Thus, we hypothesized that sequence polymorphisms in L-FABP were associated with fatty liver weight in goose. We first isolated, sequenced, and characterized the goose L-FABP gene, which had not been previously reported. The goose L-FABP gene was 2490 bp and included 4 exons coding for a 126-amino acid protein. Analysis of expression levels of the goose L-FABP gene in different tissues showed that the expression level in the liver tissue was higher than in other tissues, and was significantly higher in the liver tissue of overfed geese than in control geese. Moreover, a single nucleotide polymorphism located at 774 bp in the gene was identified in a Landes goose population. To test whether this single nucleotide polymorphism was associated with fatty liver production, liver weight and the ratio of liver to carcass weights were determined for the 3 genotypes with this single nucleotide polymorphism (TT, TG, GG) in overfed Landes geese. Our data indicate that individuals with the GG genotype had higher values for the variables measured than those with the other 2 genotypes, suggesting that L-FABP can be a selection marker for the trait of fatty liver production in goose. PMID:25729971

  13. Fatty Acid-binding Proteins (FABPs) Are Intracellular Carriers for Δ9-Tetrahydrocannabinol (THC) and Cannabidiol (CBD)*

    Elmes, Matthew W.; Kaczocha, Martin; Berger, William T.; Leung, KwanNok; Ralph, Brian P.; Wang, Liqun; Sweeney, Joseph M.; Miyauchi, Jeremy T.; Tsirka, Stella E.; Ojima, Iwao; Deutsch, Dale G.

    2015-01-01

    Δ9-Tetrahydrocannabinol (THC) and cannabidiol (CBD) occur naturally in marijuana (Cannabis) and may be formulated, individually or in combination in pharmaceuticals such as Marinol or Sativex. Although it is known that these hydrophobic compounds can be transported in blood by albumin or lipoproteins, the intracellular carrier has not been identified. Recent reports suggest that CBD and THC elevate the levels of the endocannabinoid anandamide (AEA) when administered to humans, suggesting that phytocannabinoids target cellular proteins involved in endocannabinoid clearance. Fatty acid-binding proteins (FABPs) are intracellular proteins that mediate AEA transport to its catabolic enzyme fatty acid amide hydrolase (FAAH). By computational analysis and ligand displacement assays, we show that at least three human FABPs bind THC and CBD and demonstrate that THC and CBD inhibit the cellular uptake and catabolism of AEA by targeting FABPs. Furthermore, we show that in contrast to rodent FAAH, CBD does not inhibit the enzymatic actions of human FAAH, and thus FAAH inhibition cannot account for the observed increase in circulating AEA in humans following CBD consumption. Using computational molecular docking and site-directed mutagenesis we identify key residues within the active site of FAAH that confer the species-specific sensitivity to inhibition by CBD. Competition for FABPs may in part or wholly explain the increased circulating levels of endocannabinoids reported after consumption of cannabinoids. These data shed light on the mechanism of action of CBD in modulating the endocannabinoid tone in vivo and may explain, in part, its reported efficacy toward epilepsy and other neurological disorders. PMID:25666611

  14. Fatty acid-binding proteins (FABPs) are intracellular carriers for Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD).

    Elmes, Matthew W; Kaczocha, Martin; Berger, William T; Leung, KwanNok; Ralph, Brian P; Wang, Liqun; Sweeney, Joseph M; Miyauchi, Jeremy T; Tsirka, Stella E; Ojima, Iwao; Deutsch, Dale G

    2015-04-01

    Δ(9)-Tetrahydrocannabinol (THC) and cannabidiol (CBD) occur naturally in marijuana (Cannabis) and may be formulated, individually or in combination in pharmaceuticals such as Marinol or Sativex. Although it is known that these hydrophobic compounds can be transported in blood by albumin or lipoproteins, the intracellular carrier has not been identified. Recent reports suggest that CBD and THC elevate the levels of the endocannabinoid anandamide (AEA) when administered to humans, suggesting that phytocannabinoids target cellular proteins involved in endocannabinoid clearance. Fatty acid-binding proteins (FABPs) are intracellular proteins that mediate AEA transport to its catabolic enzyme fatty acid amide hydrolase (FAAH). By computational analysis and ligand displacement assays, we show that at least three human FABPs bind THC and CBD and demonstrate that THC and CBD inhibit the cellular uptake and catabolism of AEA by targeting FABPs. Furthermore, we show that in contrast to rodent FAAH, CBD does not inhibit the enzymatic actions of human FAAH, and thus FAAH inhibition cannot account for the observed increase in circulating AEA in humans following CBD consumption. Using computational molecular docking and site-directed mutagenesis we identify key residues within the active site of FAAH that confer the species-specific sensitivity to inhibition by CBD. Competition for FABPs may in part or wholly explain the increased circulating levels of endocannabinoids reported after consumption of cannabinoids. These data shed light on the mechanism of action of CBD in modulating the endocannabinoid tone in vivo and may explain, in part, its reported efficacy toward epilepsy and other neurological disorders. PMID:25666611

  15. New ligands of the Cellular Retinoic Acid-Binding Protein 2 (CRABP2 suggest a role for this protein in chromatin remodeling

    Daniella de Barros Rossetto

    2014-08-01

    Full Text Available Retinoic acid (RA regulates the transcription of a series of genes involved in cell proliferation, differentiation and apoptosis by binding to the RA Receptor (RAR and Retinoid X Receptor (RXR heterodimers. The cellular retinoic acid-binding protein 2 (CRABP2 is involved in the transport of RA from the cytosol to specific RA receptors in the nucleus, acting as a coactivator of nuclear retinoid receptors. In order to have a better understanding of the role of CRABP2 in RA signaling, we used the yeast two-hybrid system as a tool for the identification of physical protein-protein interactions. Twenty-three putative CRABP2-interacting proteins were identified by screening in the presence of RA, five of which are related to transcription regulation or, more specifically, to the process of chromatin remodeling: t-complex 1 (TCP1; H3 histone, family 3A (H3F3A; H3 histone, family 3B (H3F3B; β-tubulin (TUBB and SR-related CTD-associated factor 1 (SCAF1. These results suggest a more direct role for CRABP2 in chromatin remodeling and may be a starting point for the elucidation of the fine-tuning control of transcription by RA receptors.

  16. Hormonal regulation of liver fatty acid-binding protein in vivo and in vitro: effects of growth hormone and insulin.

    Carlsson, L; Nilsson, I; Oscarsson, J

    1998-06-01

    Liver fatty acid-binding protein (LFABP) is an abundant protein in hepatocytes that binds most of the long chain fatty acids present in the cytosol. It is suggested to be of importance for fatty acid uptake and utilization in the hepatocyte. In the present study, the effects of bovine GH (bGH) and other hormones on the expression of LFABP and its messenger RNA (mRNA) were studied in hypophysectomized rats and in vitro using primary cultures of rat hepatocytes. One injection of bGH increased LFABP mRNA levels about 5-fold after 6 h, but there was no effect of this treatment on LFABP levels. However, 7 days of bGH treatment increased both LFABP mRNA and LFABP protein levels 2- to 5-fold. Female rats had higher levels of LFABP than male rats. Hypophysectomy of female rats, but not that of male rats, decreased LFABP levels markedly. Treatment of hypophysectomized rats with bGH for 7 days as two daily injections or as a continuous infusion increased LFABP levels to a similar degree. This finding indicates that the sex difference in the expression of LFABP is not regulated by the sexually dimorphic secretory pattern of GH. Neither insulin nor insulin-like growth factor I treatment of hypophysectomized rats for 6-7 days had any effect on LFABP mRNA or LFABP levels. In vitro, bGH dose-dependently increased the expression of LFABP mRNA, but only in the presence of insulin. Insulin alone had a marked dose-dependent effect on LFABP mRNA levels and was of importance for maintaining the expression of LFABP mRNA during the culture. Incubation with bGH increased LFABP mRNA levels within 3 h. GH had no effect on LFABP mRNA levels in the presence of actinomycin D, indicating a transcriptional effect of GH. Incubation with glucagon in vitro decreased LFABP mRNA levels markedly, indicating that glucagon, in contrast to GH, has an effect opposite that of insulin on LFABP mRNA expression. It is concluded that GH is an important regulator of LFABP in vivo and in vitro. In contrast to

  17. The acid-labile subunit of human ternary insulin-like growth factor binding protein complex in serum

    Juul, A; Møller, S; Mosfeldt-Laursen, E;

    1998-01-01

    Circulating insulin-like growth factor-I (IGF-I) is predominantly bound in the trimeric complex comprised of IGF binding protein-3 (IGFBP-3) and acid-labile subunit (ALS). Circulating concentrations of IGF-I, IGFBP-3 and ALS are believed to reflect the GH secretory status, but the clinical use of...... adults; and 4) ALS levels were below -2 SD in 57 of 79 GHD patients (sensitivity 72%) and above 2 SD in 22 of 29 patients with normal GH response (specificity 76%), which was similar, compared with the diagnostic utility of IGF-I and IGFBP-3. Finally, our findings indicate that hepatic ALS production is...... not measurable by this approach or, alternatively, that the liver is not the primary source of circulating ALS, IGF-I, or IGFBP-3 in humans. In conclusion, we have provided extensive normal data for a novel ALS assay and found that circulating ALS levels exhibit minor diurnal variation. We suggest...

  18. Association of polymorphisms in adipocyte fatty acid binding protein gene with fat-related traits in chicken

    Manhong YE; Jie WEN; Honghe CAO; Hongbin LI; Jilan CHEN; Guiping ZHAO; Maiqing ZHENG

    2008-01-01

    PCR-SSCP analysis was used to detect poly-morphic sites in chicken adipocyte fatty acid binding pro-tein (A-FABP) gene. Six Chinese local breeds, Beijing-You chicken, Dwarf chicken, Taihe silky chicken, Chong-renma chicken, Xiayan chicken, Luyuan chicken and an introduced foreign breed, Arbor Acre broiler, were used as test populations. Three PCR-SSCP loci were detected. Statistical results showed that frequencies of genotypes and alleles were significantly different in the test popula-tions. Sequence analysis revealed that C → T, G → A, and C → T transitions were responsible for the polymorph-isms. Some fat-related traits such as body weight, content of intramuscular fat (IMF) and percentage of abdominal fat (AFP) were measured in Dwarf chickens and male Beijing-You chickens. We found out that chicken quality was significantly related to different genotypes in these two populations.

  19. Identification of protein-protein binding sites by incorporating the physicochemical properties and stationary wavelet transforms into pseudo amino acid composition.

    Jia, Jianhua; Liu, Zi; Xiao, Xuan; Liu, Bingxiang; Chou, Kuo-Chen

    2016-09-01

    With the explosive growth of protein sequences entering into protein data banks in the post-genomic era, it is highly demanded to develop automated methods for rapidly and effectively identifying the protein-protein binding sites (PPBSs) based on the sequence information alone. To address this problem, we proposed a predictor called iPPBS-PseAAC, in which each amino acid residue site of the proteins concerned was treated as a 15-tuple peptide segment generated by sliding a window along the protein chains with its center aligned with the target residue. The working peptide segment is further formulated by a general form of pseudo amino acid composition via the following procedures: (1) it is converted into a numerical series via the physicochemical properties of amino acids; (2) the numerical series is subsequently converted into a 20-D feature vector by means of the stationary wavelet transform technique. Formed by many individual "Random Forest" classifiers, the operation engine to run prediction is a two-layer ensemble classifier, with the 1st-layer voting out the best training data-set from many bootstrap systems and the 2nd-layer voting out the most relevant one from seven physicochemical properties. Cross-validation tests indicate that the new predictor is very promising, meaning that many important key features, which are deeply hidden in complicated protein sequences, can be extracted via the wavelets transform approach, quite consistent with the facts that many important biological functions of proteins can be elucidated with their low-frequency internal motions. The web server of iPPBS-PseAAC is accessible at http://www.jci-bioinfo.cn/iPPBS-PseAAC , by which users can easily acquire their desired results without the need to follow the complicated mathematical equations involved. PMID:26375780

  20. Uses of Phage Display in Agriculture: Sequence Analysis and Comparative Modeling of Late Embryogenesis Abundant Client Proteins Suggest Protein-Nucleic Acid Binding Functionality

    Rekha Kushwaha

    2013-01-01

    Full Text Available A group of intrinsically disordered, hydrophilic proteins—Late Embryogenesis Abundant (LEA proteins—has been linked to survival in plants and animals in periods of stress, putatively through safeguarding enzymatic function and prevention of aggregation in times of dehydration/heat. Yet despite decades of effort, the molecular-level mechanisms defining this protective function remain unknown. A recent effort to understand LEA functionality began with the unique application of phage display, wherein phage display and biopanning over recombinant Seed Maturation Protein homologs from Arabidopsis thaliana and Glycine max were used to retrieve client proteins at two different temperatures, with one intended to represent heat stress. From this previous study, we identified 21 client proteins for which clones were recovered, sometimes repeatedly. Here, we use sequence analysis and homology modeling of the client proteins to ascertain common sequence and structural properties that may contribute to binding affinity with the protective LEA protein. Our methods uncover what appears to be a predilection for protein-nucleic acid interactions among LEA client proteins, which is suggestive of subcellular residence. The results from this initial computational study will guide future efforts to uncover the protein protective mechanisms during heat stress, potentially leading to phage-display-directed evolution of synthetic LEA molecules.

  1. Molecular cloning and functional analysis of the fatty acid-binding protein (Sp-FABP) gene in the mud crab (Scylla paramamosain)

    Xianglan Zeng; Haihui Ye; Ya'nan Yang; Guizhong Wang; Huiyang Huang

    2013-01-01

    Intracellular fatty acid-binding proteins (FABPs) are multifunctional cytosolic lipid-binding proteins found in vertebrates and invertebrates. In this work, we used RACE to obtain a full-length cDNA of Sp-FABP from the mud crab Scylla paramamosain. The open reading frame of the full length cDNA (886 bp) encoded a 136 amino acid polypeptide that showed high homology with related genes from other species. Real-time quantitative PCR identified variable levels of Sp-FABP transcripts in epidermis,...

  2. Large-scale quantitative assessment of binding preferences in protein - nucleic acid complexes

    Jakubec, Dávid; Vondrášek, Jiří

    2015-01-01

    Roč. 22, č. 1 (2015), s. 12. ISSN 1211-5894. [Discussions in Structural Molecular Biology . Annual Meeting of the Czech Society for Structural Biology /13./. 19.03.2015-21.03.2015, Nové Hrady] Institutional support: RVO:61388963 Keywords : DNA * binding preferences * ab initio calculations Subject RIV: CE - Biochemistry

  3. How does fatty acid influence anti-thyroid drugs binding and specificity toward protein human serum albumin? A blind docking simulation study

    Bijan K Paul; Nikhil Guchhait

    2014-11-01

    This study reports an AutoDock-based blind docking simulation investigation to characterize the binding interaction of a series of anti-thyroid drugs (2-mercapto-1-methylimidazole (MMI), 2-thiouracil (TU), 6-methyl-2-thiouracil (MTU), 6--propyl-2-thiouracil (PTU) with a model plasma protein Human SerumAlbumin (HSA) in the presence and absence of fatty acid (FA). The drug-protein binding efficiency is characterized in terms of binding free energy and the association constant (Ka, which is estimated as the reciprocal of the inhibition constant, Ki) of the drugs to the transport protein. The study also unveils the substantial impact of the presence of fatty acid (FA) on the binding interaction process. It is shown that in the presence of FA the drug-protein binding efficiency is markedly enhanced (except for MTU) and the binding location is changed. Hydrogen bonding interaction appears to play a governing role in the process of FA-induced modifications of binding efficiency and location.

  4. The integrity of the alpha-helical domain of intestinal fatty acid binding protein is essential for the collision-mediated transfer of fatty acids to phospholipid membranes.

    Franchini, G R; Storch, J; Corsico, B

    2008-04-01

    Intestinal FABP (IFABP) and liver FABP (LFABP), homologous proteins expressed at high levels in intestinal absorptive cells, employ markedly different mechanisms of fatty acid transfer to acceptor model membranes. Transfer from IFABP occurs during protein-membrane collisional interactions, while for LFABP transfer occurs by diffusion through the aqueous phase. In addition, transfer from IFABP is markedly faster than from LFABP. The overall goal of this study was to further explore the structural differences between IFABP and LFABP which underlie their large functional differences in ligand transport. In particular, we addressed the role of the alphaI-helix domain in the unique transport properties of intestinal FABP. A chimeric protein was engineered with the 'body' (ligand binding domain) of IFABP and the alphaI-helix of LFABP (alpha(I)LbetaIFABP), and the fatty acid transfer properties of the chimeric FABP were examined using a fluorescence resonance energy transfer assay. The results showed a significant decrease in the absolute rate of FA transfer from alpha(I)LbetaIFABP compared to IFABP. The results indicate that the alphaI-helix is crucial for IFABP collisional FA transfer, and further indicate the participation of the alphaII-helix in the formation of a protein-membrane "collisional complex". Photo-crosslinking experiments with a photoactivable reagent demonstrated the direct interaction of IFABP with membranes and further support the importance of the alphaI helix of IFABP in its physical interaction with membranes. PMID:18284926

  5. Perbedaan Kadar Liver Fatty Acid Binding Protein (L-FABP Urine Penderita Diabetes Melitus Tipe 2 dengan Normoalbuminuria dan Mikroalbuminuria

    Kristina Wiharjo

    2014-06-01

    Full Text Available Diabetes mellitus (DM is the leading cause of the end stage renal disease (ESRD. Around 20−40% patients with DM develop diabetic nephropathy and eventually progress into ESRD. Type 2 DM has a greater prevalence to develop diabetic nephropathy. Oxidative stress accumulation can increase permeability of the glomerulus which results in increased urine albumin excretion, which is divided into three groups: normoalbuminuria, microalbuminuria and macroalbuminuria. Glomerulus dysfunction occurs after tubulointerstisial renal dysfunction which decreases peritubular capillary flow that leads to tubulointerstisial hypoxia. Liver fatty acid binding protein function is to reduce hypoxia by binding oxidative stress and excretes it into urine. The aim of this study was to analyze the differences in the urine L-FABP level between normoalbuminuria and microalbuminuria type 2 DM patients. The study design was observational analytic using cross-sectional method. Subjects were 70 DM type 2 patients with normoalbuminuria (38 patients and microalbuminuria (32 patients. Statistical analysis was performed using the Mann Whitney test The results found that there were significant differences in levels of urine L-FABP between normoalbuminuria and microalbuminuria type 2 DM patients (ZM-W=3.513, p<0.001 with medians of 5 and 7 in normoalbuminuria and microalbuminuria, respectively. The urine L-FABP level increased because of the oxidative stress and hypoxia that happened before the glomerulus dysfunction. In conclusion, urine L-FABP level in patients DM type 2 with microalbuminuria is higher than that of the normoalbuminuria.

  6. Binding site of ribosomal proteins on prokaryotic 5S ribonucleic acids: a study with ribonucleases

    Douthwaite, S; Christensen, A; Garrett, R A

    1982-01-01

    stearothermophilus 5S RNA. Several protein-induced changes in the RNA structures were identified; some are possibly allosteric in nature. The two prokaryotic 5S RNAs were also incubated with total 50S subunit proteins from E. coli and B. stearothermophilus ribosomes. Homologous and heterologous reconstitution...

  7. Comparison of the Folding Mechanism of Highly Homologous Proteins in the Lipid-binding Protein Family

    The folding mechanism of two closely related proteins in the intracellular lipid binding protein family, human bile acid binding protein (hBABP) and rat bile acid binding protein (rBABP) were examined. These proteins are 77% identical (93% similar) in sequence Both of these singl...

  8. Genetic and functional analyses of the oeX174 DNA binding protein: the effects of substitutions for amino acid residues that spatially organize the two DNA binding domains

    The oeX174 DNA binding protein contains two DNA binding domains, containing a series of DNA binding basic amino acids, separated by a proline-rich linker region. Within each DNA binding domain, there is a conserved glycine residue. Glycine and proline residues were mutated and the effects on virion structure were examined. Substitutions for glycine residues yield particles with similar properties to previously characterized mutants with substitutions for DNA binding residues. Both sets of mutations share a common extragenic second-site suppressor, suggesting that the defects caused by the mutant proteins are mechanistically similar. Hence, glycine residues may optimize DNA-protein contacts. The defects conferred by substitutions for proline residues appear to be fundamentally different. The properties of the mutant particles along with the atomic structure of the virion suggest that the proline residues may act to guide the packaged DNA to the adjacent fivefold related asymmetric unit, thus preventing a chaotic packaging arrangement

  9. The fatty acid binding protein 7 (FABP7) is involved in proliferation and invasion of melanoma cells

    The molecular mechanisms underlying melanoma tumor development and progression are still not completely understood. One of the new candidates that emerged from a recent gene expression profiling study is fatty acid-binding protein 7 (FABP7), involved in lipid metabolism, gene regulation, cell growth and differentiation. We studied the functional role of FABP7 in human melanoma cell lines and using immunohistochemistry analyzed its expression pattern and clinical role in 11 nevi, 149 primary melanomas and 68 metastases. FABP7 mRNA and protein level is down-regulated following treatment of melanoma cell lines with a PKC activator (PMA) or MEK1 inhibitor (PD98059). Down-regulation of FABP7 using siRNA decreased cell proliferation and invasion but did not affect apoptosis. In clinical specimens, FABP7 was expressed in 91% of nevi, 71% of primary melanomas and 70% of metastases, with a cytoplasmic and/or nuclear localization. FABP7 expression was associated with tumor thickness in superficial spreading melanoma (P = 0.021). In addition, we observed a trend for an association between FABP7 expression and Ki-67 score (P = 0.070) and shorter relapse-free survival (P = 0.069) in this group of patients. Our data suggest that FABP7 can be regulated by PKC and the MAPK/ERK1/2 pathway through independent mechanisms in melanoma cell lines. Furthermore, FABP7 is involved in cell proliferation and invasion in vitro, and may be associated with tumor progression in melanoma

  10. Expression of the helix-loop-helix protein inhibitor of DNA binding-1 (ID-1) is activated by all-trans retinoic acid in normal human keratinocytes

    The ID (inhibitor of differentiation or DNA binding) helix-loop-helix proteins are important mediators of cellular differentiation and proliferation in a variety of cell types through regulation of gene expression. Overexpression of the ID proteins in normal human keratinocytes results in extension of culture lifespan, indicating that these proteins are important for epidermal differentiation. Our hypothesis is that the ID proteins are targets of the retinoic acid signaling pathway in keratinocytes. Retinoids, vitamin A analogues, are powerful regulators of cell growth and differentiation and are widely used in the prevention and treatment of a variety of cancers in humans. Furthermore, retinoic acid is necessary for the maintenance of epithelial differentiation and demonstrates an inhibitory action on skin carcinogenesis. We examined the effect of all-trans retinoic acid on expression of ID-1, -2, -3, and -4 in normal human keratinocytes and found that exposure of these cells to all-trans retinoic acid causes an increase in both ID-1 and ID-3 gene expression. Furthermore, our data show that this increase is mediated by increased transcription involving several cis-acting elements in the distal portion of the promoter, including a CREB-binding site, an Egr1 element, and an YY1 site. These data demonstrate that the ID proteins are direct targets of the retinoic acid signaling pathway. Given the importance of the ID proteins to epidermal differentiation, these results suggest that IDs may be mediating some of the effects of all-trans retinoic acid in normal human keratinocytes

  11. Low abdominal NIRS values and elevated plasma intestinal fatty acid-binding protein in a premature piglet model of necrotizing enterocolitis

    To identify early markers of necrotizing enterocolitis (NEC), we hypothesized that continuous abdominal near-infrared spectroscopy (A-NIRS) measurement of splanchnic tissue oxygen saturation and intermittent plasma intestinal fatty-acid binding protein (pI-FABP) measured every 6 hours can detect NEC...

  12. Molecular Properties of Guar Gum and Pectin Modify Cecal Bile Acids, Microbiota, and Plasma Lipopolysaccharide-Binding Protein in Rats.

    Ghaffarzadegan, Tannaz; Marungruang, Nittaya; Fåk, Frida; Nyman, Margareta

    2016-01-01

    Bile acids (BAs) act as signaling molecules in various physiological processes, and are related to colonic microbiota composition as well as to different types of dietary fat and fiber. This study investigated whether guar gum and pectin-two fibers with distinct functional characteristics-affect BA profiles, microbiota composition, and gut metabolites in rats. Low- (LM) or high-methoxylated (HM) pectin, and low-, medium-, or high-molecular-weight (MW) guar gum were administered to rats that were fed either low- or high-fat diets. Cecal BAs, short-chain fatty acids (SCFA) and microbiota composition, and plasma lipopolysaccharide-binding protein (LBP) levels were analyzed, by using novel methodologies based on gas chromatography (BAs and SCFAs) and 16S rRNA gene sequencing on the Illumina MiSeq platform. Strong correlations were observed between cecal BA and SCFA levels, microbiota composition, and portal plasma LBP levels in rats on a high-fat diet. Notably, guar gum consumption with medium-MW increased the cecal amounts of cholic-, chenodeoxycholic-, and ursodeoxycholic acids as well as α-, β-, and ω-muricholic acids to a greater extent than other types of guar gum or the fiber-free control diet. In contrast, the amounts of cecal deoxycholic- and hyodeoxycholic acid were reduced with all types of guar gum independent of chain length. Differences in BA composition between pectin groups were less obvious, but cecal levels of α- and ω-muricholic acids were higher in rats fed LM as compared to HM pectin or the control diet. The inflammatory marker LBP was downregulated in rats fed medium-MW guar gum and HM pectin; these two fibers decreased the cecal abundance of Oscillospira and an unclassified genus in Ruminococcaceae, and increased that of an unclassified family in RF32. These results indicate that the molecular properties of guar gum and pectin are important for their ability to modulate cecal BA formation, gut microbiota composition, and high-fat diet induced

  13. Molecular Properties of Guar Gum and Pectin Modify Cecal Bile Acids, Microbiota, and Plasma Lipopolysaccharide-Binding Protein in Rats.

    Tannaz Ghaffarzadegan

    Full Text Available Bile acids (BAs act as signaling molecules in various physiological processes, and are related to colonic microbiota composition as well as to different types of dietary fat and fiber. This study investigated whether guar gum and pectin-two fibers with distinct functional characteristics-affect BA profiles, microbiota composition, and gut metabolites in rats. Low- (LM or high-methoxylated (HM pectin, and low-, medium-, or high-molecular-weight (MW guar gum were administered to rats that were fed either low- or high-fat diets. Cecal BAs, short-chain fatty acids (SCFA and microbiota composition, and plasma lipopolysaccharide-binding protein (LBP levels were analyzed, by using novel methodologies based on gas chromatography (BAs and SCFAs and 16S rRNA gene sequencing on the Illumina MiSeq platform. Strong correlations were observed between cecal BA and SCFA levels, microbiota composition, and portal plasma LBP levels in rats on a high-fat diet. Notably, guar gum consumption with medium-MW increased the cecal amounts of cholic-, chenodeoxycholic-, and ursodeoxycholic acids as well as α-, β-, and ω-muricholic acids to a greater extent than other types of guar gum or the fiber-free control diet. In contrast, the amounts of cecal deoxycholic- and hyodeoxycholic acid were reduced with all types of guar gum independent of chain length. Differences in BA composition between pectin groups were less obvious, but cecal levels of α- and ω-muricholic acids were higher in rats fed LM as compared to HM pectin or the control diet. The inflammatory marker LBP was downregulated in rats fed medium-MW guar gum and HM pectin; these two fibers decreased the cecal abundance of Oscillospira and an unclassified genus in Ruminococcaceae, and increased that of an unclassified family in RF32. These results indicate that the molecular properties of guar gum and pectin are important for their ability to modulate cecal BA formation, gut microbiota composition, and high

  14. Upregulation of peroxisome proliferator-activated receptors and liver fatty acid binding protein in hepatic cells of broiler chicken supplemented with conjugated linoleic acids

    Suriya Kumari Ramiah

    2015-09-01

    Full Text Available Since conjugated linoleic acid (CLA has structural and physiological characteristics similar to peroxisome proliferators, it is hypothesized that CLA would upregulate peroxisome proliferator-activated receptor (PPAR and liver fatty acid binding protein (LFABP in the liver of broiler chicken. The aim of the present study was to determine fatty acid composition of liver in CLA-fed broiler chickens and the genes associated with hepatic lipid metabolism. A total of 180-day-old broiler chicks were randomly assigned to two diets containing 0 and 2.5% CLA and fed for 6 weeks. Fatty acid (FA composition of liver and PPAR α and γ and L-FABP were analyzed. It has been demonstrated that CLA was found in the liver of CLA-feed chicken compared to control group. Hepatic PPAR α and γ mRNA levels were upregulated 1.2 and 3-fold in CLA-fed chickens compared to chickens fed diet without CLA respectively. A similar response of upregulation was observed for L-FABP mRNA expression. Our data highlights the role of PPARs as a core regulator in the regulation of lipid metabolism in chicken liver.

  15. Plasma protein-binding and CSF concentrations of valproic acid in man following acute oral dosing.

    Rapeport, W. G.; Mendelow, A D; French, G; MacPherson, P.; Teasdale, E; Agnew, E; Thompson, G G; Brodie, M J

    1983-01-01

    Simultaneous cerebrospinal fluid (CSF), total and free plasma valproic acid (VPA) concentrations were measured in 17 patients receiving two weight-adjusted VPA doses as seizure prophylaxis prior to diagnostic myelography or cisternography. Free drug concentrations were similar when measured by equilibrium dialysis (ED) at 37 degrees C for 24 h (Dianorm) or by a novel ultrafiltration (UF) method (EMIT freelevel system 1, SYVA) (ED:2.3-35.5 mg-1; UF:1.3-33.6 mg-1; r = 0.78, P less than 0.002). ...

  16. Elevation of urinary liver-type fatty acid binding protein after cardiac catheterization related to cardiovascular events

    Kamijo-Ikemori A

    2015-08-01

    Full Text Available Atsuko Kamijo-Ikemori,1,3 Nobuyuki Hashimoto,2 Takeshi Sugaya,1 Katsuomi Matsui,1 Mikako Hisamichi,1 Yugo Shibagaki,1 Fumihiko Miyake,2 Kenjiro Kimura1 1Department of Nephrology and Hypertension, 2Department of Cardiology, 3Department of Anatomy, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan Purpose: Contrast medium (CM induces tubular hypoxia via endothelial damage due to direct cytotoxicity or viscosity. Urinary liver-type fatty acid binding protein (L-FABP increases along with tubular hypoxia and may be a detector of systemic circulation injury. The aim of this study was to evaluate the clinical usefulness of detecting increases in urinary L-FABP levels due to administration of CM, as a prognostic biomarker for cardiovascular disease in patients without occurrence of CM-induced nephropathy undergoing cardiac catheterization procedure (CCP. Methods: Retrospective longitudinal analyses of the relationship between urinary L-FABP levels and occurrence of cardiovascular events were performed (n=29. Urinary L-FABP was measured by ELISA before CCP, and at 6, 12, 24, and 48 hours after CCP. Results: Urinary L-FABP levels were significantly higher at 12 hours (P<0.05 and 24 hours (P<0.005 after CCP compared with before CCP, only in the patients with occurrence of cardiovascular events (n=17, but not in those without cardiovascular events (n=12. The parameter with the largest area under the curve (0.816 for predicting the occurrence of cardiovascular events was the change in urinary L-FABP at 24 hours after CCP. The difference in urinary L-FABP levels (ΔL-FABP ≥11.0 µg/g creatinine between before CCP and at 24 hours after CCP was a risk factor for the occurrence of cardiovascular events (hazard ratio, 4.93; 95% confidence interval, 1.27–19.13; P=0.021. Conclusion: Measurement of urinary L-FABP before CCP and at 24 hours after CCP in patients with mild to moderate renal dysfunction may be an important indicator for risk

  17. Large-Scale Quantitative Assessment of Binding Preferences in Protein-Nucleic Acid Complexes.

    Jakubec, Dávid; Hostas, Jirí; Laskowski, Roman A; Hobza, Pavel; Vondrásek, Jirí

    2015-04-14

    The growing number of high-quality experimental (X-ray, NMR) structures of protein–DNA complexes has sufficient enough information to assess whether universal rules governing the DNA sequence recognition process apply. While previous studies have investigated the relative abundance of various modes of amino acid–base contacts (van der Waals contacts, hydrogen bonds), relatively little is known about the energetics of these noncovalent interactions. In the present study, we have performed the first large-scale quantitative assessment of binding preferences in protein–DNA complexes by calculating the interaction energies in all 80 possible amino acid–DNA base combinations. We found that several mutual amino acid–base orientations featuring bidentate hydrogen bonds capable of unambiguous one-to-one recognition correspond to unique minima in the potential energy space of the amino acid–base pairs. A clustering algorithm revealed that these contacts form a spatially well-defined group offering relatively little conformational freedom. Various molecular mechanics force field and DFT-D ab initio calculations were performed, yielding similar results. PMID:26894243

  18. Expression and Characterization of Human Heart Type Fatty Acid Binding Protein in Pichia Pastoris

    2006-01-01

    H-FABP is regarded as a tissue-specific protein existing only in myocardial cells. It is released from the cardiac tissue and gets into the plasma when a heart attack occurs; the myocardial infarction is a good case in point. As a result, the detection of H-FABP will be an early and important biomarker for the disease concerned. The objective of the study is to prepare the recombinant H-FABP by aeukaryotic expression system, pichia, to produce the protein mimicking natural H-FABP, as an immunogen for the production of the specific antibody. A gene fragment encoding H-FABP was cloned in the expressing vector pPICZα, after sequencing. The recombinant plasmid was transformed into the competent cells of the X-33 strain by means of electroporation. The expression of the target peptide indueed by methanol was screened by means of Western blotting, with the available MAb( Clone 6B6 ). Highly expressive engineer strains were obtained. The production of recombinant H-FABP under induction was about 0.7 g/L, with an Mr of 14.5 kDa and recognized by a commercially available MAb (Clone 6B6). The recombinant vector was successfully constructed. Following this, H-FABP was expressed in X-33, and it would become the source of the preparation of specific antibodies, to develop diagnostic kits.

  19. Interaction between acid-labile subunit and insulin-like growth factor binding protein 3 expressed in Xenopus oocytes.

    Choi, Kyung-Yi; Lee, Dong-Hee

    2002-03-31

    The acid-labile subunit (ALS) associates with the insulinlike growth factor (IGF)-I or II, and the IGF binding protein-3 (IGFBP-3) in order to form a 150-kD complex in the circulation. This complex may regulate the serum IGFs by restricting them in the vascular system and promoting their endocrine actions. Little is known about how ALS binds to IGFBP3, which connects the IGFs to ALS. Xenopus oocyte was utilized to study the function of ALS in assembling IGFs into the ternary complexes. Xenopus oocyte was shown to correctly translate in vitro transcribed mRNAs of ALS and IGFBP3. IGFBP3 and ALS mRNAs were injected in a mixture, and their products were immunoprecipitated by antisera against ALS and IGFBP3. Contrary to traditional reports that ALS interacts only with IGF-bound IGFBP3, this study shows that ALS is capable of forming a binary complex with IGFBP3 in the absence of IGF. When cross-linked by disuccinimidyl suberate, the band that represents the ALSIGFBP3 complex was evident on the PAGE. IGFBP3 movement was monitored according to the distribution between the hemispheres. Following a localized translation in the vegetal hemisphere, IGFBP3 remained in the vegetal half in the presence of ALS. However, the mutant IGFBP3 freely diffused into the animal half, despite the presence of ALS, which is different from the wild type IGFBP3. This study, therefore, suggests that ALS may play an important role in sequestering IGFBP3 polypeptides via the intermolecular aggregation. Studies using this heterologous model will lead to a better understanding of the IGFBP3 and ALS that assemble into the ternary structure and circulate the IGF system. PMID:12297028

  20. Fatty acid-binding protein 4 impairs the insulin-dependent nitric oxide pathway in vascular endothelial cells

    Aragonès Gemma

    2012-06-01

    Full Text Available Abstract Background Recent studies have shown that fatty acid-binding protein 4 (FABP4 plasma levels are associated with impaired endothelial function in type 2 diabetes (T2D. In this work, we analysed the effect of FABP4 on the insulin-mediated nitric oxide (NO production by endothelial cells in vitro. Methods In human umbilical vascular endothelial cells (HUVECs, we measured the effects of FABP4 on the insulin-mediated endothelial nitric oxide synthase (eNOS expression and activation and on NO production. We also explored the impact of exogenous FABP4 on the insulin-signalling pathway (insulin receptor substrate 1 (IRS1 and Akt. Results We found that eNOS expression and activation and NO production are significantly inhibited by exogenous FABP4 in HUVECs. FABP4 induced an alteration of the insulin-mediated eNOS pathway by inhibiting IRS1 and Akt activation. These results suggest that FABP4 induces endothelial dysfunction by inhibiting the activation of the insulin-signalling pathway resulting in decreased eNOS activation and NO production. Conclusion These findings provide a mechanistic linkage between FABP4 and impaired endothelial function in diabetes, which leads to an increased cardiovascular risk.

  1. The brown adipocyte protein CIDEA promotes lipid droplet fusion via a phosphatidic acid-binding amphipathic helix

    Barneda, David; Planas-Iglesias, Joan; Gaspar, Maria L; Mohammadyani, Dariush; Prasannan, Sunil; Dormann, Dirk; Han, Gil-Soo; Jesch, Stephen A; Carman, George M; Kagan, Valerian; Parker, Malcolm G; Ktistakis, Nicholas T; Klein-Seetharaman, Judith; Dixon, Ann M; Henry, Susan A; Christian, Mark

    2015-01-01

    Maintenance of energy homeostasis depends on the highly regulated storage and release of triacylglycerol primarily in adipose tissue, and excessive storage is a feature of common metabolic disorders. CIDEA is a lipid droplet (LD)-protein enriched in brown adipocytes promoting the enlargement of LDs, which are dynamic, ubiquitous organelles specialized for storing neutral lipids. We demonstrate an essential role in this process for an amphipathic helix in CIDEA, which facilitates embedding in the LD phospholipid monolayer and binds phosphatidic acid (PA). LD pairs are docked by CIDEA trans-complexes through contributions of the N-terminal domain and a C-terminal dimerization region. These complexes, enriched at the LD–LD contact site, interact with the cone-shaped phospholipid PA and likely increase phospholipid barrier permeability, promoting LD fusion by transference of lipids. This physiological process is essential in adipocyte differentiation as well as serving to facilitate the tight coupling of lipolysis and lipogenesis in activated brown fat. DOI: http://dx.doi.org/10.7554/eLife.07485.001 PMID:26609809

  2. Liver fatty acid-binding protein (L-FABP) promotes cellular angiogenesis and migration in hepatocellular carcinoma.

    Ku, Chung-Yu; Liu, Yu-Huei; Lin, Hsuan-Yuan; Lu, Shao-Chun; Lin, Jung-Yaw

    2016-04-01

    Liver fatty acid-binding protein (L-FABP) is abundant in hepatocytes and known to be involved in lipid metabolism. Overexpression of L-FABP has been reported in various cancers; however, its role in hepatocellular carcinoma (HCC) remains unclear. In this study, we investigated L-FABP and its association with vascular endothelial growth factors (VEGFs) in 90 HCC patients. We found that L-FABP was highly expressed in their HCC tissues, and that this expression was positively correlated with that of VEGF-A. Additionally, L-FABP significantly promoted tumor growth and metastasis in a xenograft mouse model. We also assessed the mechanisms of L-FABP activity in tumorigenesis; L-FABP was found to associate with VEGFR2 on membrane rafts and subsequently activate the Akt/mTOR/P70S6K/4EBP1 and Src/FAK/cdc42 pathways, which resulted in up-regulation of VEGF-A accompanied by an increase in both angiogenic potential and migration activity. Our results thus suggest that L-FABP could be a potential target for HCC chemotherapy. PMID:26919097

  3. Mercury-binding proteins of Mytilus edulis

    Roesijadi, G.; Morris, J. E.; Calabrese, A.

    1981-11-01

    Mytilus edulis possesses low molecular weight, mercury-binding proteins. The predominant protein isolated from gill tissue is enriched in cysteinyl residues (8%) and possesses an amino acid composition similar to cadmium-binding proteins of mussels and oysters. Continuous exposure of mussels to 5 ..mu..g/l mercury results in spillover of mercury from these proteins to high molecular weight proteins. Antibodies to these proteins have been isolated, and development of immunoassays is presently underway. Preliminary studies to determine whether exposure of adult mussels to mercury will result in induction of mercury-binding proteins in offspring suggest that such proteins occur in larvae although additional studies are indicated for a conclusive demonstration.

  4. Metformin reduces lipid accumulation in macrophages by inhibiting FOXO1-mediated transcription of fatty acid-binding protein 4

    Objective: The accumulation of lipids in macrophages contributes to the development of atherosclerosis. Strategies to reduce lipid accumulation in macrophages may have therapeutic potential for preventing and treating atherosclerosis and cardiovascular complications. The antidiabetic drug metformin has been reported to reduce lipid accumulation in adipocytes. In this study, we examined the effects of metformin on lipid accumulation in macrophages and investigated the mechanisms involved. Methods and results: We observed that metformin significantly reduced palmitic acid (PA)-induced intracellular lipid accumulation in macrophages. Metformin promoted the expression of carnitine palmitoyltransferase I (CPT-1), while reduced the expression of fatty acid-binding protein 4 (FABP4) which was involved in PA-induced lipid accumulation. Quantitative real-time PCR showed that metformin regulates FABP4 expression at the transcriptional level. We identified forkhead transcription factor FOXO1 as a positive regulator of FABP4 expression. Inhibiting FOXO1 expression with FOXO1 siRNA significantly reduced basal and PA-induced FABP4 expression. Overexpression of wild-type FOXO1 and constitutively active FOXO1 significantly increased FABP4 expression, whereas dominant negative FOXO1 dramatically decreased FABP4 expression. Metformin reduced FABP4 expression by promoting FOXO1 nuclear exclusion and subsequently inhibiting its activity. Conclusions: Taken together, these results suggest that metformin reduces lipid accumulation in macrophages by repressing FOXO1-mediated FABP4 transcription. Thus, metformin may have a protective effect against lipid accumulation in macrophages and may serve as a therapeutic agent for preventing and treating atherosclerosis in metabolic syndrome.

  5. Serum liver fatty acid binding protein levels correlate positively with obesity and insulin resistance in Chinese young adults.

    Juan Shi

    Full Text Available BACKGROUND: Liver fatty acid-binding protein (FABP1 plays an inconclusive role in adiposity. We investigated the association of serum FABP1 levels with obesity and insulin resistance in Chinese young people under 30 years old. METHODOLOGY AND PRINCIPAL FINDINGS: Cross-sectional analysis including 200 obese and 172 normal-weight subjects matched for age and sex, anthropometric measurements were performed and serum FABP1 and biochemical characteristics were measured. Insulin resistance was determined by homeostasis model assessment of insulin resistance (HOMA-IR and by the insulin sensitivity index (S(i derived from Bergman's minimal model. FABP1 levels in obese subjects were significantly higher than those in normal-weight subjects (p<0.001 and the significance remained after adjustment for age, gender, alanine and aspartate aminotransferases (p<0.001. Serum FABP1 levels were significantly correlated with many metabolic-related parameters, with BMI and triglycerides as the independent determinants. FABP1 levels remained an independent risk factor of insulin resistance assessed by binary S(i (OR = 1.868 per SD unit, 95% CI [1.035-3.373], p = 0.038 after adjustment for age, sex, BMI, waist circumference, systolic blood pressure, serum triacylglycerol, total cholesterol, HDL- and LDL-cholesterol,. FABP1 levels were also elevated with an increasing number of components of the metabolic syndrome (p for trend <0.001. Multiple regression modeling for the MetS and its components demonstrated that hypertriglyceridemia and low HDL-cholesterol were significantly correlated to serum FABP1 levels. CONCLUSIONS AND SIGNIFICANCE: Serum FABP1 correlates positively with obesity and insulin resistance in Chinese young adults. Our data supports the fact that FABP1 might be an important mediator participating in fatty acid metabolism and energy balance.

  6. Metformin reduces lipid accumulation in macrophages by inhibiting FOXO1-mediated transcription of fatty acid-binding protein 4

    Song, Jun [Qilu Hospital, Shandong University, Jinan, Shandong (China); Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States); Ren, Pingping; Zhang, Lin [Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States); Wang, Xing Li [Qilu Hospital, Shandong University, Jinan, Shandong (China); Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States); Chen, Li [Qilu Hospital, Shandong University, Jinan, Shandong (China); Shen, Ying H., E-mail: hyshen@bcm.edu [Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States)

    2010-02-26

    Objective: The accumulation of lipids in macrophages contributes to the development of atherosclerosis. Strategies to reduce lipid accumulation in macrophages may have therapeutic potential for preventing and treating atherosclerosis and cardiovascular complications. The antidiabetic drug metformin has been reported to reduce lipid accumulation in adipocytes. In this study, we examined the effects of metformin on lipid accumulation in macrophages and investigated the mechanisms involved. Methods and results: We observed that metformin significantly reduced palmitic acid (PA)-induced intracellular lipid accumulation in macrophages. Metformin promoted the expression of carnitine palmitoyltransferase I (CPT-1), while reduced the expression of fatty acid-binding protein 4 (FABP4) which was involved in PA-induced lipid accumulation. Quantitative real-time PCR showed that metformin regulates FABP4 expression at the transcriptional level. We identified forkhead transcription factor FOXO1 as a positive regulator of FABP4 expression. Inhibiting FOXO1 expression with FOXO1 siRNA significantly reduced basal and PA-induced FABP4 expression. Overexpression of wild-type FOXO1 and constitutively active FOXO1 significantly increased FABP4 expression, whereas dominant negative FOXO1 dramatically decreased FABP4 expression. Metformin reduced FABP4 expression by promoting FOXO1 nuclear exclusion and subsequently inhibiting its activity. Conclusions: Taken together, these results suggest that metformin reduces lipid accumulation in macrophages by repressing FOXO1-mediated FABP4 transcription. Thus, metformin may have a protective effect against lipid accumulation in macrophages and may serve as a therapeutic agent for preventing and treating atherosclerosis in metabolic syndrome.

  7. Gender difference in plasma fatty-acid-binding protein 4 levels in patients with chronic obstructive pulmonary disease

    Zhang, Xue; Li, Diandian; Wang, Hao; Pang, Caishuang; Wu, Yanqiu; Wen, Fuqiang

    2016-01-01

    COPD (chronic obstructive pulmonary disease) is characterized by airway inflammation and increases the likelihood of the development of atherosclerosis. Recent studies have indicated that FABP4 (fatty-acid-binding protein 4), an intracellular lipid chaperone of low molecular mass, plays an important role in the regulation of inflammation and atherosclerosis. We carried out a preliminary clinical study aiming at investigating the relationships between circulating FABP4 levels in patients with COPD and inflammation and lung function. We enrolled 50 COPD patients and 39 healthy controls in the study. Lung function tests were performed in all subjects. Plasma levels of FABP4 and adiponectin, TNFα (tumour necrosis factor α) and CRP (C-reactive protein) were measured. The correlations between FABP4 and lung function, adipokine (adiponectin), inflammatory factors and BMI (body mass index) were analysed. Compared with both males with COPD and healthy females, plasma FABP4 levels in females with COPD were significantly increased. Adiponectin and CRP levels were significantly higher in patients with COPD. Furthermore, we found that FABP4 levels were inversely correlated with FEV1% predicted (FEV1 is forced expiratory volume in 1 s) and positively correlated with adiponectin and TNFα in COPD patients. In addition, a positive correlation between plasma FABP4 and CRP was found in females with COPD. However, FABP4 levels were not correlated with BMI. Our results underline a gender difference in FABP4 secretion in stable COPD patients. Further studies are warranted to clarify the exact role of FABP4 in the pathogenesis of COPD. PMID:26823558

  8. Interaction of Adipocyte Fatty Acid-binding Protein (AFABP) and JAK2: AFABP/aP2 AS A REGULATOR OF JAK2 SIGNALING*

    Thompson, Brian R.; Mazurkiewicz-Muñoz, Anna M.; Suttles, Jill; Carter-Su, Christin; Bernlohr, David A

    2009-01-01

    Adipocyte fatty acid-binding protein (AFABP/aP2) facilitates the intracellular solubilization and trafficking of lipids within the aqueous environment of the cell. Studies in the AFABP/aP2 knock-out mouse suggest that the protein may have roles in cellular processes broader than lipid transport. We present herein the finding that AFABP/aP2 interacts with JAK2 in a fatty acid-dependent manner. This interaction was established using yeast two-hybrid analysis, co-immunopr...

  9. Brain-type and liver-type fatty acid-binding proteins: new tumor markers for renal cancer?

    Moch Holger

    2009-07-01

    Full Text Available Abstract Background Renal cell carcinoma (RCC is the most common renal neoplasm. Cancer tissue is often characterized by altered energy regulation. Fatty acid-binding proteins (FABP are involved in the intracellular transport of fatty acids (FA. We examined the level of brain-type (B and liver-type (L FABP mRNA and the protein expression profiles of both FABPs in renal cell carcinoma. Methods Paired tissue samples of cancerous and noncancerous kidney parts were investigated. Quantitative RT-PCR, immunohistochemistry and western blotting were used to determine B- and L-FABP in tumor and normal tissues. The tissue microarray (TMA contained 272 clinico-pathologically characterized renal cell carcinomas of the clear cell, papillary and chromophobe subtype. SPSS 17.0 was used to apply crosstables (χ2-test, correlations and survival analyses. Results B-FABP mRNA was significantly up-regulated in renal cell carcinoma. In normal tissue B-FABP mRNA was very low or often not detectable. RCC with a high tumor grading (G3 + G4 showed significantly lower B-FABP mRNA compared with those with a low grading (G1 + G2. Western blotting analysis detected B-FABP in 78% of the cases with a very strong band but in the corresponding normal tissue it was weak or not detectable. L-FABP showed an inverse relationship for mRNA quantification and western blotting. A strong B-FABP staining was present in 52% of the tumor tissues contained in the TMA. In normal renal tissue, L-FABP showed a moderate to strong immunoreactivity in proximal tubuli. L-FABP was expressed at lower rates compared with the normal tissues in 30.5% of all tumors. There was no correlation between patient survival times and the staining intensity of both FABPs. Conclusion While B-FABP is over expressed in renal cell carcinoma in comparison to normal renal tissues L-FABP appears to be reduced in tumor tissue. Although the expression behavior was not related to the survival outcome of the RCC patients

  10. Brain-type and liver-type fatty acid-binding proteins: new tumor markers for renal cancer?

    Renal cell carcinoma (RCC) is the most common renal neoplasm. Cancer tissue is often characterized by altered energy regulation. Fatty acid-binding proteins (FABP) are involved in the intracellular transport of fatty acids (FA). We examined the level of brain-type (B) and liver-type (L) FABP mRNA and the protein expression profiles of both FABPs in renal cell carcinoma. Paired tissue samples of cancerous and noncancerous kidney parts were investigated. Quantitative RT-PCR, immunohistochemistry and western blotting were used to determine B- and L-FABP in tumor and normal tissues. The tissue microarray (TMA) contained 272 clinico-pathologically characterized renal cell carcinomas of the clear cell, papillary and chromophobe subtype. SPSS 17.0 was used to apply crosstables (χ2-test), correlations and survival analyses. B-FABP mRNA was significantly up-regulated in renal cell carcinoma. In normal tissue B-FABP mRNA was very low or often not detectable. RCC with a high tumor grading (G3 + G4) showed significantly lower B-FABP mRNA compared with those with a low grading (G1 + G2). Western blotting analysis detected B-FABP in 78% of the cases with a very strong band but in the corresponding normal tissue it was weak or not detectable. L-FABP showed an inverse relationship for mRNA quantification and western blotting. A strong B-FABP staining was present in 52% of the tumor tissues contained in the TMA. In normal renal tissue, L-FABP showed a moderate to strong immunoreactivity in proximal tubuli. L-FABP was expressed at lower rates compared with the normal tissues in 30.5% of all tumors. There was no correlation between patient survival times and the staining intensity of both FABPs. While B-FABP is over expressed in renal cell carcinoma in comparison to normal renal tissues L-FABP appears to be reduced in tumor tissue. Although the expression behavior was not related to the survival outcome of the RCC patients, it can be assumed that these changes indicate fundamental

  11. LIVER TYPE FATTY ACID BINDING PROTEIN (L-FABP) GENE ABLATION REDUCES NUCLEAR LIGAND DISTRIBUTION AND PEROXISOME PROLIFERATOR ACTIVATED RECEPTOR-α ACTIVITY IN CULTURED PRIMARY HEPATOCYTES1

    McIntosh, Avery L.; Atshaves, Barbara P.; Hostetler, Heather A.; Huang, Huan; Davis, Jason; Lyuksyutova, Olga I.; Landrock, Danilo; Kier, Ann B.; Schroeder, Friedhelm

    2009-01-01

    The effect of liver type fatty acid binding protein (L-FABP) gene ablation on the uptake and distribution of long chain fatty acids (LCFA) to the nucleus by real-time laser scanning confocal imaging and peroxisome proliferator activated receptor-α (PPARα) activity was examined in cultured primary hepatocytes from livers wild-type L-FABP+/+ and gene ablated L-FABP−/− mice. Cultured primary hepatocytes from livers of L-FABP−/− mice exhibited: (i) reduced oxidation of palmitic acid, a common die...

  12. Characterization of DNA Binding and Retinoic Acid Binding Properties of Retinoic Acid Receptor

    Yang, Na; Schule, Roland; Mangelsdorf, David J.; Evans, Ronald M.

    1991-05-01

    High-level expression of the full-length human retinoic acid receptor (RAR) α and the DNA binding domain of the RAR in Escherichia coli was achieved by using a T7 RNA polymerase-directed expression system. After induction, full-length RAR protein was produced at an estimated level of 20% of the total bacterial proteins. Both intact RAR molecules and the DNA binding domain bind to the cognate DNA response element with high specificity in the absence of retinoic acid. However, this binding is enhanced to a great extent upon the addition of eukaryotic cell extracts. The factor responsible for this enhancement is heat-sensitive and forms a complex with RAR that binds to DNA and exhibits a distinct migration pattern in the gel-mobility-shift assay. The interaction site of the factor with RAR is localized in the 70-amino acid DNA binding region of RAR. The hormone binding ability of the RARα protein was assayed by a charcoal absorption assay and the RAR protein was found to bind to retinoic acid with a K_d of 2.1 x 10-10 M.

  13. Serum Fatty Acid-Binding Protein 4 Is a Predictor of Cardiovascular Events in End-Stage Renal Disease

    Furuhashi, Masato; Ishimura, Shutaro; Ota, Hideki; Hayashi, Manabu; Nishitani, Takahiro; Tanaka, Marenao; Yoshida, Hideaki; Shimamoto, Kazuaki; Hotamisligil, Gökhan S.; Miura, Tetsuji

    2011-01-01

    Background Fatty acid-binding protein 4 (FABP4/A-FABP/aP2), a lipid chaperone, is expressed in both adipocytes and macrophages. Recent studies have shown that FABP4 is secreted from adipocytes and that FABP4 level is associated with obesity, insulin resistance, and atherosclerosis. However, little is known about the impact of FABP4 concentrations on prognosis. We tested the hypothesis that FABP4 level predicts prognosis of patients with end-stage renal disease (ESRD), a group at high risk for atherosclerosis-associated morbidity and mortality. Methods and Results Biochemical markers including FABP4 were determined in 61 ESRD patients on chronic hemodialysis (HD). Serum FABP4 level in females (404.2±30.5 ng/ml) was significantly higher than that in males (315.8±30.0 ng/ml), and the levels in ESRD patients were about 20-times higher than those in age-, gender- and body mass index (BMI)-matched control subjects with normal renal function. FABP4 level was decreased by 57.2% after HD and was positively correlated with blood pressure, BMI, and levels of lipids and insulin. Multiple regression analysis indicated that HD duration, BMI, and triglycerides level were independent determinants for FABP4 level. ESRD patients with high FABP4 levels had higher cardiovascular mortality during the 7-year follow-up period. Cox proportional hazard regression analysis showed that logarithmically transformed FABP4 level was an independent predictor of cardiovascular death adjusted for age, gender, HD duration, BMI, and triglycerides level (hazard ratio, 7.75; 95% CI, 1.05–25.31). Conclusion These findings suggest that FABP4 level, being related to adiposity and metabolic disorders, is a novel predictor of cardiovascular mortality in ESRD. PMID:22102888

  14. Human heart-type fatty acid-binding protein as an early diagnostic marker of doxorubicin cardiac toxicity

    Ashraf H. ElGhandour

    2009-04-01

    Full Text Available Progressive cardiotoxicity following treatment with doxorubicin-based chemotherapy in patients with non-Hodgkin’s lymphoma (NHL may lead to late onset cardiomyopathy. So, early prediction of toxicity can lead to prevention of heart failure in these patients. The aim of this work was to investigate the role of H-FABP as an early diagnostic marker of anthracycline-induced cardiac toxicity together with brain natriuretic peptide (BNP as an indication of ventricular dysfunction in such patients. Our study was conducted on 40 NHL patients who received 6 cycles of a doxorubicin containing chemotherapy protocol (CHOP, not exceeding the total allowed dose of doxorubicin (500 mg/m2. Ten healthy controls were included in our study. Human heart-type fatty acid binding protein (H-FABP was assessed 24 hours after the first cycle of CHOP. Plasma levels of BNP were estimated both before starting chemotherapy and after the last cycle of CHOP. Resting echocardiography was also performed before and at the end of chemotherapy cycles. The ejection fraction (EF of 8 of our patients decreased below 50% at the end of the sixth cycle. Elevated levels of both H-FABP and BNP were found in all patients wth EF below 50% and both markers showed a positive correlation with each other. We concluded that H-FABP may serve as a reliable early marker for prediction of cardiomyopathy induced by doxorubicin. Thus, in patients with elevated H-FABP, alternative treatment modalities with no cardiac toxicity may be considered in order to prevent subsequent heart failure in these patients.

  15. Fatty Acid binding protein 4 is associated with carotid atherosclerosis and outcome in patients with acute ischemic stroke.

    Sverre Holm

    Full Text Available BACKGROUND AND PURPOSE: Fatty acid binding protein 4 (FABP4 has been shown to play an important role in macrophage cholesterol trafficking and associated inflammation. To further elucidate the role of FABP4 in atherogenesis in humans, we examined the regulation of FABP4 in carotid atherosclerosis and ischemic stroke. METHODS: We examined plasma FABP4 levels in asymptomatic (n = 28 and symptomatic (n = 31 patients with carotid atherosclerosis, as well as in 202 subjects with acute ischemic stroke. In a subgroup of patients we also analysed the expression of FABP4 within the atherosclerotic lesion. In addition, we investigated the ability of different stimuli with relevance to atherosclerosis to regulate FABP4 expression in monocytes/macrophages. RESULTS: FABP4 levels were higher in patients with carotid atherosclerosis, both systemically and within the atherosclerotic lesion, with particular high mRNA levels in carotid plaques from patients with the most recent symptoms. Immunostaining of carotid plaques localized FABP4 to macrophages, while activated platelets and oxidized LDL were potent stimuli for FABP4 expression in monocytes/macrophages in vitro. When measured at the time of acute ischemic stroke, high plasma levels of FABP4 were significantly associated with total and cardiovascular mortality during follow-up, although we did not find that addition of FABP4 to the fully adjusted multivariate model had an effect on the prognostic discrimination for all-cause mortality as assessed by c-statistics. CONCLUSIONS: FABP4 is linked to atherogenesis, plaque instability and adverse outcome in patients with carotid atherosclerosis and acute ischemic stroke.

  16. Molecular cloning and functional analysis of the fatty acid-binding protein (Sp-FABP gene in the mud crab (Scylla paramamosain

    Xianglan Zeng

    2013-01-01

    Full Text Available Intracellular fatty acid-binding proteins (FABPs are multifunctional cytosolic lipid-binding proteins found in vertebrates and invertebrates. In this work, we used RACE to obtain a full-length cDNA of Sp-FABP from the mud crab Scylla paramamosain. The open reading frame of the full length cDNA (886 bp encoded a 136 amino acid polypeptide that showed high homology with related genes from other species. Real-time quantitative PCR identified variable levels of Sp-FABP transcripts in epidermis, eyestalk, gill, heart, hemocytes, hepatopancreas, muscle, ovary, stomach and thoracic ganglia. In ovaries, Sp-FABP expression increased gradually from stage I to stage IV of development and decreased in stage V. Sp-FABP transcripts in the hepatopancreas and hemocytes were up-regulated after a bacterial challenge with Vibrio alginnolyficus. These results suggest that Sp-FABP may be involved in the growth, reproduction and immunity of the mud crab.

  17. Clinical experience of immunotherapy based on oleic acid bound to glycosylated vitamin d-binding protein in localised and metastatic adenocarcinoma of the pancreas

    Lynda Thyer; Branca, Jacopo J. V.; Margit Taubmann

    2014-01-01

    Adenocarcinoma of the pancreas still carries a dramatically poor prognosis and the survival rate for this disease has not improved substantially in the past 40 years. Therefore, new treatment options are urgently needed and this need motivates oncologists to search for novel approaches such as immunotherapy. Here we report two clinical cases successfully treated with an integrative immunotherapeutic approach based on oleic acid bound to glycosylated vitamin D-binding protein (OA-GcMAF). Consi...

  18. Fatty acid binding protein 3 (fabp3) is associated with insulin, lipids and cardiovascular phenotypes of the metabolic syndrome through epigenetic modifications in a northern european family population

    Zhang, Yi; Kent, Jack W; Lee, Adam; Cerjak, Diana; ALI Omar; Diasio, Robert; Olivier, Michael; Blangero, John; Carless, Melanie A.; Kissebah, Ahmed H.

    2013-01-01

    Background Fatty acid-binding proteins (FABPs) play regulatory roles at the nexus of lipid metabolism and signaling. Dyslipidemia in clinical manifestation frequently co-occurs with obesity, insulin resistance and hypertension in the Metabolic Syndrome (MetS). Animal studies have suggested FABPs play regulatory roles in expressing MetS phenotypes. In our family cohort of Northern European descent, transcript levels in peripheral white blood cells (PWBCs) of a key FABPs, FABP3, is correlated w...

  19. Rapid Diagnosis of acute kidney injury (AKI) associated with cardiac surgery, using the liver type fatty acid binding protein (L-FABP) biomarker

    Mirbagheri L; Master of Biochemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran; Farhadi N; Taghipour H R; Mirbagheri M; Nourani M R

    2012-01-01

    Background and objectives: cardiac surgery is often associated with acutekidney injury (AKI). Nowadays, AKI is typically diagnosed by an increase inserum creatinine, which is a delayed and unreliable biomarker. Recent studiesrecommended using the liver type fatty acid binding protein (L-FABP) as anearly biomarker.Material and Methods: The urine samples of 18 adult patients undergoingcardiac surgery were collected in different times before (2, 4,8,24 hour) andafter cardiac surgery for detectio...

  20. Contribution of Specific Amino Acid Changes in Penicillin Binding Protein 1 to Amoxicillin Resistance in Clinical Helicobacter pylori isolates ▿

    Qureshi, Nadia N.; Morikis, Dimitrios; Schiller, Neal L.

    2010-01-01

    Amoxicillin is commonly used to treat Helicobacter pylori, a major cause of peptic ulcers, stomach cancer, and B-cell mucosa-associated lymphoid tissue lymphoma. Amoxicillin resistance in H. pylori is increasing steadily, especially in developing countries, leading to treatment failures. In this study, we characterize the mechanism of amoxicillin resistance in the U.S. clinical isolate B258. Transformation of amoxicillin-susceptible strain 26695 with the penicillin binding protein 1 gene (pbp...

  1. 113Cd NMR studies of a 1:1 Cd adduct with an 18-residue finger peptide from HIV-1 nucleic acid binding protein, p7

    The Zn2+ and Cd2+ adducts with the 18-residue peptide comprising the amino acid sequence of the first finger (residues 13 through 30) of retroviral nucleic acid binding proteins p7 from HIV-1 (the causative agent of AIDS) have been prepared. 1H NMR data indicate that the metal adducts are 1:1 compounds that are stable in aqueous solutions for at least a month. The 113Cd NMR spectral results for the adduct are presented and analyzed. 26 references, 3 figures

  2. BINDING ISOTHERMS SURFACTANT-PROTEINS

    Elena Irina Moater; Cristiana Radulescu; Ionica Ionita

    2011-01-01

    The interactions between surfactants and proteins shows some similarities with interactions between surfactants and polymers, but the hydrophobic amphoteric nature of proteins and their secondary and tertiary structure components make them different from conventional polymer systems. Many studies from the past about surfactant - proteins bonding used the dialysis techniques. Other techniques used to determine the binding isotherm, included ultrafiltration, ultracentrifugation, potentiometry, ...

  3. Analysis of the regulation of fatty acid binding protein 7 expression in human renal carcinoma cell lines

    Sugiyama Takayuki

    2011-07-01

    Full Text Available Abstract Background Improving the treatment of renal cell carcinoma (RCC will depend on the development of better biomarkers for predicting disease progression and aiding the design of appropriate therapies. One such marker may be fatty acid binding protein 7 (FABP7, also known as B-FABP and BLBP, which is expressed normally in radial glial cells of the developing central nervous system and cells of the mammary gland. Melanomas, glioblastomas, and several types of carcinomas, including RCC, overexpress FABP7. The abundant expression of FABP7 in primary RCCs compared to certain RCC-derived cell lines may allow the definition of the molecular components of FABP7's regulatory system. Results We determined FABP7 mRNA levels in six RCC cell lines. Two were highly expressed, whereas the other and the embryonic kidney cell line (HEK293 were weakly expressed FABP7 transcripts. Western blot analysis of the cell lines detected strong FABP7 expression only in one RCC cell line. Promoter activity in the RCC cell lines was 3- to 21-fold higher than that of HEK293. Deletion analysis demonstrated that three FABP7 promoter regions contributed to upregulated expression in RCC cell lines, but not in the HEK293 cell. Competition analysis of gel shifts indicated that OCT1, OCT6, and nuclear factor I (NFI bound to the FABP7 promoter region. Supershift experiments indicated that BRN2 (POU3F2 and NFI bound to the FABP7 promoter region as well. There was an inverse correlation between FABP7 promoter activity and BRN2 mRNA expression. The FABP7-positive cell line's NFI-DNA complex migrated faster than in other cell lines. Levels of NFIA mRNA were higher in the HEK293 cell line than in any of the six RCC cell lines. In contrast, NFIC mRNA expression was lower in the HEK293 cell line than in the six RCC cell lines. Conclusions Three putative FABP7 promoter regions drive reporter gene expression in RCC cell lines, but not in the HEK293 cell line. BRN2 and NFI may be key

  4. Protein Dynamics in an RNA Binding Protein

    Hall, Kathleen

    2006-03-01

    Using ^15N NMR relaxation measurements, analyzed with the Lipari-Szabo formalism, we have found that the human U1A RNA binding protein has ps-ns motions in those loops that make contact with RNA. Specific mutations can alter the extent and pattern of motions, and those proteins inevitably lose RNA binding affinity. Proteins with enhanced mobility of loops and termini presumably lose affinity due to increased conformational sampling by those parts of the protein that interact directly with RNA. There is an entropic penalty associated with locking down those elements upon RNA binding, in addition to a loss of binding efficiency caused by the increased number of conformations adopted by the protein. However, in addition to local conformational heterogeneity, analysis of molecular dynamics trajectories by Reorientational Eigenmode Dynamics reveals that loops of the wild type protein undergo correlated motions that link distal sites across the binding surface. Mutations that disrupt correlated motions result in weaker RNA binding, implying that there is a network of interactions across the surface of the protein. (KBH was a Postdoctoral Fellow with Al Redfield from 1985-1990). This work was supported by the NIH (to KBH) and NSF (SAS).

  5. Direct comparison of mice null for liver or intestinal fatty acid-binding proteins reveals highly divergent phenotypic responses to high fat feeding.

    Gajda, Angela M; Zhou, Yin Xiu; Agellon, Luis B; Fried, Susan K; Kodukula, Sarala; Fortson, Walter; Patel, Khamoshi; Storch, Judith

    2013-10-18

    The enterocyte expresses two fatty acid-binding proteins (FABP), intestinal FABP (IFABP; FABP2) and liver FABP (LFABP; FABP1). LFABP is also expressed in liver. Despite ligand transport and binding differences, it has remained uncertain whether these intestinally coexpressed proteins, which both bind long chain fatty acids (FA), are functionally distinct. Here, we directly compared IFABP(-/-) and LFABP(-/-) mice fed high fat diets containing long chain saturated or unsaturated fatty acids, reasoning that providing an abundance of dietary lipid would reveal unique functional properties. The results showed that mucosal lipid metabolism was indeed differentially modified, with significant decreases in FA incorporation into triacylglycerol (TG) relative to phospholipid (PL) in IFABP(-/-) mice, whereas LFABP(-/-) mice had reduced monoacylglycerol incorporation in TG relative to PL, as well as reduced FA oxidation. Interestingly, striking differences were found in whole body energy homeostasis; LFABP(-/-) mice fed high fat diets became obese relative to WT, whereas IFABP(-/-) mice displayed an opposite, lean phenotype. Fuel utilization followed adiposity, with LFABP(-/-) mice preferentially utilizing lipids, and IFABP(-/-) mice preferentially metabolizing carbohydrate for energy production. Changes in body weight and fat may arise, in part, from altered food intake; mucosal levels of the endocannabinoids 2-arachidonoylglycerol and arachidonoylethanolamine were elevated in LFABP(-/-), perhaps contributing to increased energy intake. This direct comparison provides evidence that LFABP and IFABP have distinct roles in intestinal lipid metabolism; differential intracellular functions in intestine and in liver, for LFABP(-/-) mice, result in divergent downstream effects at the systemic level. PMID:23990461

  6. Molecular cloning and expression of a novel keratinocyte protein (psoriasis-associated fatty acid-binding protein [PA-FABP]) that is highly up-regulated in psoriatic skin and that shares similarity to fatty acid-binding proteins

    Madsen, Peder; Rasmussen, H H; Leffers, H;

    1992-01-01

    as MRP 14, L1, or calprotectin; calgranulin A or MRP 8; and cystatin A or stefin A. Here, we have cloned and sequenced the cDNA (clone 1592) encoding a new member of this group of low-molecular-weight proteins [isoelectric focusing (IEF) SSP 3007 in the keratinocyte 2D gel protein database] that we...

  7. Fatty acids and hypolipidemic drugs regulate peroxisome proliferator-activated receptors α- and γ-mediated gene expression via liver fatty acid binding protein: A signaling path to the nucleus

    Wolfrum, Christian; Borrmann, Carola M.; Börchers, Torsten; Spener, Friedrich

    2001-01-01

    Peroxisome proliferator-activated receptor α (PPARα) is a key regulator of lipid homeostasis in hepatocytes and target for fatty acids and hypolipidemic drugs. How these signaling molecules reach the nuclear receptor is not known; however, similarities in ligand specificity suggest the liver fatty acid binding protein (L-FABP) as a possible candidate. In localization studies using laser-scanning microscopy, we show that L-FABP and PPARα colocalize in the nucleus of...

  8. The influence of feeding linoleic, gamma-linolenic and docosahexaenoic acid rich oils on rat brain tumor fatty acids composition and fatty acid binding protein 7 mRNA expression

    Abdi Khosro

    2008-11-01

    Full Text Available Abstract Background Experimental studies indicate that gamma linolenic acid (GLA and docosahexaenoic acid (DHA may inhibit glioma cells growth but effects of oral consumption of these fatty acids on brain tumor fatty acid composition have not been determined in vivo. Methods GLA oil (GLAO; 72% GLA, DHA oil (DHAO; 73% DHA were fed to adult wistar rats (1 mL/rat/day starting one week prior to C6 glioma cells implantation and continued for two weeks after implantation. Control group were fed same amount of high linoleic acid safflower oil (74–77% linoleic acid. Fatty acid composition of tumor samples was determined in a set of 8–12 animals in each group and serum fatty acid in 6 animals per each group. Gene expression of tumor fatty acid binding protein 7 (FABP7, epidermal growth factor receptor (EGFR, peroxisome proliferator activated receptor γ (PPAR-γ and retinoid × receptor-α (RXR-α were determined in a set of 18 animals per group. Results DHAO feeding increased EPA of brain tumors and decreased ratio of n-6/n-3 fatty acids. Serum levels of EPA were also increased in DHAO group. A similar trend in serum and tumor levels of DHA were observed in DHAO group but it did not achieve statistical significance. GLAO increased serum concentration of GLA but had no significant effect on tumor GLA or dihomo-gamma linolenic acid (DGLA concentrations. Gene expression of FABP7 was up-regulated in tumors of DHAO group but no other significant effects were observed on EGFR, PPAR-γ or RXR-α expression, and expression of these genes in tumors of GLAO were not different from SFO group. Conclusion Dietary supplementation of DHA containing oil could be an effective way to increase levels of long chain n-3 fatty acids in brain tumors and this increase may be mediated partly by up-regulation of FABP7 expression.

  9. Amino acid sequences mediating vascular cell adhesion molecule 1 binding to integrin alpha 4: homologous DSP sequence found for JC polyoma VP1 coat protein

    Michael Andrew Meyer

    2013-07-01

    Full Text Available The JC polyoma viral coat protein VP1 was analyzed for amino acid sequences homologies to the IDSP sequence which mediates binding of VLA-4 (integrin alpha 4 to vascular cell adhesion molecule 1. Although the full sequence was not found, a DSP sequence was located near the critical arginine residue linked to infectivity of the virus and binding to sialic acid containing molecules such as integrins (3. For the JC polyoma virus, a DSP sequence was found at residues 70, 71 and 72 with homology also noted for the mouse polyoma virus and SV40 virus. Three dimensional modeling of the VP1 molecule suggests that the DSP loop has an accessible site for interaction from the external side of the assembled viral capsid pentamer.

  10. The Trypanosoma cruzi nucleic acid binding protein Tc38 presents changes in the intramitochondrial distribution during the cell cycle

    Nardelli Sheila C

    2009-02-01

    Full Text Available Abstract Background Tc38 of Trypanosoma cruzi has been isolated as a single stranded DNA binding protein with high specificity for the poly [dT-dG] sequence. It is present only in Kinetoplastidae protozoa and its sequence lacks homology to known functional domains. Tc38 orthologues present in Trypanosoma brucei and Leishmania were proposed to participate in quite different cellular processes. To further understand the function of this protein in Trypanosoma cruzi, we examined its in vitro binding to biologically relevant [dT-dG] enriched sequences, its expression and subcellular localization during the cell cycle and through the parasite life stages. Results By using specific antibodies, we found that Tc38 protein from epimastigote extracts participates in complexes with the poly [dT-dG] probe as well as with the universal minicircle sequence (UMS, a related repeated sequence found in maxicircle DNA, and the telomeric repeat. However, we found that Tc38 predominantly localizes into the mitochondrion. Though Tc38 is constitutively expressed through non-replicating and replicating life stages of T. cruzi, its subcellular localization in the unique parasite mitochondrion changes according to the cell cycle stage. In epimastigotes, Tc38 is found only in association with kDNA in G1 phase. From the S to G2 phase the protein localizes in two defined and connected spots flanking the kDNA. These spots disappear in late G2 turning into a diffuse dotted signal which extends beyond the kinetoplast. This later pattern is more evident in mitosis and cytokinesis. Finally, late in cytokinesis Tc38 reacquires its association with the kinetoplast. In non-replicating parasite stages such as trypomastigotes, the protein is found only surrounding the entire kinetoplast structure. Conclusions The dynamics of Tc38 subcellular localization observed during the cell cycle and life stages support a major role for Tc38 related to kDNA replication and maintenance.

  11. Conjugated linoleic acid and fatty acid binding protein as antioxidants Ácido linoleico conjugado y proteína transportadora de ácidos grasos como antioxidantes

    V.A. Piergiacomi

    2006-12-01

    Full Text Available Studies were carried out to determine the effect of conjugated linoleic acid (CLA and rat liver cytosolic protein enriched in fatty acid binding protein (FABP on the non-enzymatic lipid peroxidation of rat liver microsomes. The inhibition of lipid peroxidation was more evident when the FABP containing fraction obtained from CLA-group was used with either kind of microsomes (CLA and control. The chemiluminescence and polyunsaturated fatty acid composition of rat liver microsomes changed after CLA treatment. When native and peroxidized microsomes obtained from control group were compared, the most affected polyunsaturated fatty acids were: C18:2, C18:3 and C20:4, while in CLA-group C20:4 was mainly peroxidized The simultaneous analysis of chemiluminescence and fatty acid composition demonstrated that CLA and FABP play a role protecting rat liver microsomes against the harmful effect of lipid peroxidation.El objetivo del trabajo fue determinar el efecto del ácido linoleico conjugado (ALC y de la proteína citosólica de hígado de rata enriquecida en Proteína Transportadora de Ácidos Grasos (PTAG, sobre la peroxidación no enzimática de lípidos de microsomas hepáticos de rata. Luego de la incubación de éstos en un sistema ascorbato-Fe++ se observó que el total de cpm/mg de proteina originada por quimioluminiscencia fue menor en los microsomas obtenidos de las ratas del grupo ALC respecto a los del grupo control. Cuando la fracción PTAG obtenida del grupo ALC fue agregada a la peroxidación de microsomas de ambos grupos de animales ALC y control, la inhibición de la lipoperoxidación fue más evidente. Además se encontró que ambas fracciones PTAG, tanto la obtenida de animales del grupo ALC como la obtenida del grupo control, tuvieron mayor efecto como antioxidantes cuando se usaron microsomas ALC respecto a microsomas control. La composición de ácidos grasos de los microsomas cambió luego del tratamiento con ALC. Comparando

  12. Influence of berberine combining with atorvastatin on serum high-sensitivity C-reactive protein and adipocyte fatty acid-binding protein in patients with acute ischemic stroke

    Fei-qi ZHU

    2015-01-01

    Full Text Available Objective To observe the influence of berberine combining with atorvastatin on serum high-sensitivity C-reactive protein (hs-CRP and adipocyte fatty acid-binding protein (A-FABP in patients with acute ischemic stroke.  Methods Ischemic stroke patients (N = 55 were randomized into 3 groups: atorvastatin 20 mg/d (N = 28, atorvastatin 40 mg/d (N = 11 and berberine 0.40 g three times a day + atorvastatin 20 mg/d (combined treatment, N = 16. They were treated for 3 months. The expression changes of serum hs-CRP and A-FABP before and after treatment were compared among 3 groups.  Results There were significant decreases between before and 3 months after treatment on the expression of hs-CRP and A-FABP in 3 groups (P = 0.023, 0.000. After treatment, both the expression of hs-CRP and A-FABP significantly decreased, and the decreases were (1.69 ± 2.29 and (281.43 ± 311.05 mg/L in atorvastatin 20 mg/d group, (7.81 ± 12.48 and (321.59 ± 289.35 mg/L in atorvastatin 40 mg/d group, and (2.16 ± 3.34 and (376.55 ± 249.72 mg/L in combined treatment group. However, there was no significant difference among 3 groups (P > 0.05, for all, and there was no correlation between drugs and observation time points (P > 0.05, for all.  Conclusions The effect of berberine combined with atorvastatin on hs-CRP and A-FABP is similar to atorvastation (40 mg/d therapy. DOI: 10.3969/j.issn.1672-6731.2015.01.010

  13. Synthesis, characterization of α-amino acid Schiff base derived Ru/Pt complexes: Induces cytotoxicity in HepG2 cell via protein binding and ROS generation

    Alsalme, Ali; Laeeq, Sameen; Dwivedi, Sourabh; Khan, Mohd. Shahnawaz; Al Farhan, Khalid; Musarrat, Javed; Khan, Rais Ahmad

    2016-06-01

    We have synthesized two new complexes of platinum (1) and ruthenium (2) with α-amino acid, L-alanine, and 2,3-dihydroxybenzaldehyde derived Schiff base (L). The ligand and both complexes were characterized by using elemental analysis and several other spectroscopic techniques viz; IR, 1H, 13C NMR, EPR, and ESI-MS. Furthermore, the protein-binding ability of synthesized complexes was monitored by UV-visible, fluorescence and circular dichroism techniques with a model protein, human serum albumin (HSA). Both the PtL2 and RuL2 complexes displayed significant binding towards HSA. Also, in vitro cytotoxicity assay for both complexes was carried out on human hepatocellular carcinoma cancer (HepG2) cell line. The results showed concentration-dependent inhibition of cell viability. Moreover, the generation of reactive oxygen species was also evaluated, and results exhibited substantial role in cytotoxicity.

  14. Grafting of protein-protein binding sites

    2000-01-01

    A strategy for grafting protein-protein binding sites is described. Firstly, key interaction residues at the interface of ligand protein to be grafted are identified and suitable positions in scaffold protein for grafting these key residues are sought. Secondly, the scaffold proteins are superposed onto the ligand protein based on the corresponding Ca and Cb atoms. The complementarity between the scaffold protein and the receptor protein is evaluated and only matches with high score are accepted. The relative position between scaffold and receptor proteins is adjusted so that the interface has a reasonable packing density. Then the scaffold protein is mutated to corresponding residues in ligand protein at each candidate position. And the residues having bad steric contacts with the receptor proteins, or buried charged residues not involved in the formation of any salt bridge are mutated. Finally, the mutated scaffold protein in complex with receptor protein is co-minimized by Charmm. In addition, we deduce a scoring function to evaluate the affinity between mutated scaffold protein and receptor protein by statistical analysis of rigid binding data sets.

  15. Different functions of intestinal and liver-type fatty acid-binding proteins in intestine and in whole body energy homeostasis.

    Lagakos, William Stacy; Gajda, Angela Marie; Agellon, Luis; Binas, Bert; Choi, Victor; Mandap, Bernadette; Russnak, Timothy; Zhou, Yin Xiu; Storch, Judith

    2011-05-01

    It has long been known that mammalian enterocytes coexpress two members of the fatty acid-binding protein (FABP) family, the intestinal FABP (IFABP) and the liver FABP (LFABP). Both bind long-chain fatty acids and have similar though not identical distributions in the intestinal tract. While a number of in vitro properties suggest the potential for different functions, the underlying reasons for expression of both proteins in the same cells are not known. Utilizing mice genetically lacking either IFABP or LFABP, we directly demonstrate that each of the enterocyte FABPs participates in specific pathways of intestinal lipid metabolism. In particular, LFABP appears to target fatty acids toward oxidative pathways and dietary monoacylglycerols toward anabolic pathways, while IFABP targets dietary fatty acids toward triacylglycerol synthesis. The two FABP-null models also displayed differences in whole body response to fasting, with LFABP-null animals losing less fat-free mass and IFABP-null animals losing more fat mass relative to wild-type mice. The metabolic changes observed in both null models appear to occur by nontranscriptional mechanisms, supporting the hypothesis that the enterocyte FABPs are specifically trafficking their ligands to their respective metabolic fates. PMID:21350192

  16. Heterologous expression of the bovine cardiac fatty acid-binding protein (H-FABP) in the yeast Yarrowia lipolytica: biochemical and physiological studies

    Little is known about the metabolic significance of fatty acid-binding proteins (FABPs) in lipid metabolism in vivo. The bovine cardiac FABP (H-FABP) was expressed in the yeast Y. lipolytica to investigate its function in vivo. An expression system was established using homologous LEU2 -transcription signals and characterized by applying E.coli beta-glucuronidase (beta-GUS). This marker represents a new and highly sensitive reporter system in Y. lipolytica. The heterologous H-FABP made up 0.05-0.1% of the yeast cytosolic protein. The heterologous H-FABP reacted with an antibody raised against the authentic H-FABP and had the identical size of 14 kDa. Despite its capacity to bind fatty acids (FA) in vitro, it did not affect the intracellular partitioning of incorporated radioactively labeled palmitic or oleic acid between phospholipids (PL), the free fatty acid fraction and triacylglycerols (TAG). Uptake, desaturation and beta-oxidation of the particular FA, as well as de novo biosynthesis of FA were unaffected. The investigations on intracellular partitioning of FA demonstrated different incorporation characteristics of FA in dependence of growth and temperature conditions, indicating selective mechanisms in membrane assembly. Furthermore, data suggest modification (desaturation/elongation) of FA in the PL-fraction followed by transesterification into the TAG. The investigations allowed new insights into regulatory aspects of lipid metabolism in Y. lipolytica. (author)

  17. Two crystal forms of a helix-rich fatty acid- and retinol-binding protein, Na-FAR-1, from the parasitic nematode Necator americanus

    Na-FAR-1, a fatty acid- and retinol-binding protein, was expressed in bacteria, purified and crystallized. Crystals grew in two different morphologies under the same conditions. Na-FAR-1 is an unusual α-helix-rich fatty acid- and retinol-binding protein from Necator americanus, a blood-feeding intestinal parasitic nematode of humans. It belongs to the FAR protein family, which is unique to nematodes; no structural information is available to date for FAR proteins from parasites. Crystals were obtained with two different morphologies that corresponded to different space groups. Crystal form 1 exhibited space group P432 (unit-cell parameters a = b = c = 120.80 Å, α = β = γ = 90°) and diffracted to 2.5 Å resolution, whereas crystal form 2 exhibited space group F23 (unit-cell parameters a = b = c = 240.38 Å, α = β = γ = 90°) and diffracted to 3.2 Å resolution. Crystal form 2 showed signs of significant twinning

  18. Oligomerization transforms human APOBEC3G from an efficient enzyme to a slowly dissociating nucleic acid-binding protein

    Chaurasiya, Kathy R.; McCauley, Micah J.; Wang, Wei; Qualley, Dominic F.; Wu, Tiyun; Kitamura, Shingo; Geertsema, Hylkje; Chan, Denise S. B.; Hertz, Amber; Iwatani, Yasumasa; Levin, Judith G.; Musier-Forsyth, Karin; Rouzina, Ioulia; Williams, Mark C.

    2014-01-01

    The human APOBEC3 proteins are a family of DNA-editing enzymes that play an important role in the innate immune response against retroviruses and retrotransposons. APOBEC3G is a member of this family that inhibits HIV-1 replication in the absence of the viral infectivity factor Vif. Inhibition of HIV replication occurs by both deamination of viral single-stranded DNA and a deamination-independent mechanism. Efficient deamination requires rapid binding to and dissociation from ssDNA. However, a relatively slow dissociation rate is required for the proposed deaminase-independent roadblock mechanism in which APOBEC3G binds the viral template strand and blocks reverse transcriptase-catalysed DNA elongation. Here, we show that APOBEC3G initially binds ssDNA with rapid on-off rates and subsequently converts to a slowly dissociating mode. In contrast, an oligomerization-deficient APOBEC3G mutant did not exhibit a slow off rate. We propose that catalytically active monomers or dimers slowly oligomerize on the viral genome and inhibit reverse transcription.

  19. Cloning and tissue distribution of rat hear fatty acid binding protein mRNA: identical forms in heart and skeletal muscle

    A fatty acid binding protein (FABP) as been identified and characterized in rat heart, but the function and regulation of this protein are unclear. In this study the cDNA for rat heart FABP was cloned from a λ gt11 library. Sequencing of the cDNA showed an open reading frame coding for a protein with 133 amino acids and a calculated size of 14,776 daltons. Several differences were found between the sequence determined from the cDNA and that reported previously by protein sequencing techniques. Northern blot analysis using rat heart FABP cDNA as a probe established the presence of an abundant mRNA in rat heart about 0.85 kilobases in length. This mRNA was detected, but was not abundant, in fetal heart tissue. Tissue distribution studies showed a similar mRNA species in red, but not white, skeletal muscle. In general, the mRNA tissue distribution was similar to that of the protein detected by Western immunoblot analysis, suggesting that heart FABP expression may be regulated at the transcriptional level. S1 nuclease mapping studies confirmed that the mRNA hybridized to rat heart FABP cDNA was identical in heart and red skeletal muscle throughout the entire open reading frame. The structural differences between heart FABP and other members of this multigene family may be related to the functional requirements of oxidative muscle for fatty acids as a fuel source

  20. Loss of sialic acid binding domain redirects protein σ1 to enhance M cell-directed vaccination.

    Dagmara Zlotkowska

    Full Text Available Ovalbumin (OVA genetically fused to protein sigma 1 (pσ1 results in tolerance to both OVA and pσ1. Pσ1 binds in a multi-step fashion, involving both protein- and carbohydrate-based receptors. To assess the relative pσ1 components responsible for inducing tolerance and the importance of its sialic binding domain (SABD for immunization, modified OVA-pσ1, termed OVA-pσ1(short, was deleted of its SABD, but with its M cell targeting moiety intact, and was found to be immunostimulatory and enhanced CD4(+ and CD8(+ T cell proliferation. When used to nasally immunize mice given with and without cholera toxin (CT adjuvant, elevated SIgA and serum IgG responses were induced, and OVA-pσ1(s was more efficient for immunization than native OVA+CT. The immune antibodies (Abs were derived from elevated Ab-forming cells in the upper respiratory tissues and submaxillary glands and were supported by mixed Th cell responses. Thus, these studies show that pσ1(s can be fused to vaccines to effectively elicit improved SIgA responses.

  1. Isolation of a Thiamine-binding Protein from Rice Germ and Distribution of Similar Proteins.

    Shimizu, M; Yoshida, T; Toda, T; Iwashima, A; Mitsunaga, T

    1996-01-01

    A thiamine-binding protein was purified from rice germ (Oryza sativa L.) by extraction, salting-out with ammonium sulfate, and column chromatography. From the results of molecular mass, Kd and Bmax values for thiamine-binding, binding specificity for thiamine phosphates and analog, the protein was suggested to be identical to the thiamine-binding protein in rice bran. The thiamine-binding protein w as more efficiently purified from rice germ than from rice bran. The protein was rich in glutamic acid (and/or glutamine) and glycine. The protein did not show immunological similarity to thiamine-binding proteins in buckwheat and sesame seeds. However proteins similar to the thiamine-binding protein from rice germ existed in gramineous seeds. They were suggested to have thiamine-binding activity and to be of the same molecular mass as the thiamine-binding protein. PMID:27299548

  2. Urine Liver-Type Fatty Acid-Binding Protein and Kidney Injury Molecule-1 in HIV-Infected Patients Receiving Combined Antiretroviral Treatment Based on Tenofovir

    Jabłonowska, Elżbieta; Wójcik, Kamila; Piekarska, Anna

    2014-01-01

    The aim of this study was to determine the presence of kidney tubular damage in the absence of overt evidence of glomerular dysfunction (GFR>60 ml/min without proteinuria) in HIV-infected patients receiving antiretroviral therapy. Urine kidney injury molecule-1 (KIM-1) and liver-type fatty acid-binding protein (L-FABP) levels were measured by ELISA and expressed as a ratio to creatinine. Sixty-six patients (median age 38 years) and 10 healthy controls (median age 35.5 years) were included in ...

  3. THE INTEGRITY OF THE α-HELICAL DOMAIN OF INTESTINAL FATTY ACID BINDING PROTEIN IS ESSENTIAL FOR THE COLLISION-MEDIATED TRANSFER OF FATTY ACIDS TO PHOSPHOLIPID MEMBRANES

    Franchini, G. R.; Storch, J.; Corsico, B.

    2008-01-01

    Intestinal FABP (IFABP) and liver FABP (LFABP), homologous proteins expressed at high levels in intestinal absorptive cells, employ markedly different mechanisms of fatty acid transfer to acceptor model membranes. Transfer from IFABP occurs during protein-membrane-collisional interactions, while for LFABP transfer occurs by diffusion through the aqueous phase. In addition, transfer from IFABP is markedly faster than from LFABP. The overall goal of this study was to further explore the structu...

  4. 肝型脂肪酸结合蛋白研究进展%Progress in liver type fatty acid binding protein

    王南南; 徐力致; 王亚平

    2012-01-01

    Liver fatty acid binding protein (L-FABP) which mainly expresses in liver, intestine and kidney, is an important member of FABP family. It is found that L-FABP is related to the translocation of saturated fatty acid, unsaturated fatty acid, cholesterol, bile acid and so on. Many studies have indicated that L-FABP was involved in fatty liver, cirrhosis and hepatocarcinoma. Moreover, L-FABP can be an appropriate biomarker in predicting the progression of liver injury. Recent researches have demonstrated that u-LFABP might be a new tool in the prediction of diabetic nephropathy in type 1 diabetic patients. Besides, L-FABP levels reflect the severity of diabetic nephropathy accurately in type 2 diabetes. This article aims to review the characteristics, conformation of L-FABP, and its relationship with some diseases.%肝型脂肪酸结合蛋白(liver fatty acid binding protein,L-FABP)是脂肪酸结合蛋白(fatty acid binding proteins,FABPs)家族重要的成员,在肝脏、小肠、肾脏等组织中均有表达.L-FABP在不饱和脂肪酸、饱和脂肪酸、胆固醇、胆汁酸等转运过程中扮演重要角色.目前研究显示L-FABP在脂肪肝、肝硬化以及肝癌发生发展中起到重要作用,并有望作为肝损伤的早期检测指标.此外,新近研究发现尿中L-FABP水平还可以用于预测1型糖尿病患者的临床结局.在2型糖尿病中,尿中L-FABP与糖尿病性肾病的病程有密切关系.主要就L-FABP的特性、结构及其与疾病的关系做一综述.

  5. Crystal Structures of the Staphylococcal Toxin SSL5 in Complex With Sialyl-Lewis X Reveal a Conserved Binding Site That Shares Common Features With Viral And Bacterial Sialic Acid-Binding Proteins

    Baker, H.M.; Basu, I.; Chung, M.C.; Caradoc-Davies, T.; Fraser, J.D.; Baker, E.N.

    2009-06-02

    Staphylococcus aureus is a significant human pathogen. Among its large repertoire of secreted toxins is a group of staphylococcal superantigen-like proteins (SSLs). These are homologous to superantigens but do not have the same activity. SSL5 is shown here to bind to human granulocytes and to the cell surface receptors for human IgA (Fc alphaRI) and P-selectin [P-selectin glycoprotein ligand-1 (PSGL-1)] in a sialic acid (Sia)-dependent manner. Co-crystallization of SSL5 with the tetrasaccharide sialyl Lewis X (sLe(X)), a key determinant of PSGL-1 binding to P-selectin, led to crystal structures of the SSL5-sLe(X) complex at resolutions of 1.65 and 2.75 A for crystals at two pH values. In both structures, sLe(X) bound to a specific site on the surface of the C-terminal domain of SSL5 in a conformation identical with that bound by P-selectin. Conservation of the key carbohydrate binding residues indicates that this ability to bind human glycans is shared by a substantial subgroup of the SSLs, including SSL2, SSL3, SSL4, SSL5, SSL6, and SSL11. This indicates that the ability to target human glycans is an important property of this group of toxins. Structural comparisons also showed that the Sia binding site in SSL5 contains a substructure that is shared by other Sia binding proteins from bacteria as well as viruses and represents a common binding motif.

  6. Direct Comparison of Mice Null for Liver or Intestinal Fatty Acid-binding Proteins Reveals Highly Divergent Phenotypic Responses to High Fat Feeding*

    Gajda, Angela M.; Zhou, Yin Xiu; Agellon, Luis B.; Fried, Susan K.; Kodukula, Sarala; Fortson, Walter; Patel, Khamoshi; Storch, Judith

    2013-01-01

    The enterocyte expresses two fatty acid-binding proteins (FABP), intestinal FABP (IFABP; FABP2) and liver FABP (LFABP; FABP1). LFABP is also expressed in liver. Despite ligand transport and binding differences, it has remained uncertain whether these intestinally coexpressed proteins, which both bind long chain fatty acids (FA), are functionally distinct. Here, we directly compared IFABP−/− and LFABP−/− mice fed high fat diets containing long chain saturated or unsaturated fatty acids, reasoning that providing an abundance of dietary lipid would reveal unique functional properties. The results showed that mucosal lipid metabolism was indeed differentially modified, with significant decreases in FA incorporation into triacylglycerol (TG) relative to phospholipid (PL) in IFABP−/− mice, whereas LFABP−/− mice had reduced monoacylglycerol incorporation in TG relative to PL, as well as reduced FA oxidation. Interestingly, striking differences were found in whole body energy homeostasis; LFABP−/− mice fed high fat diets became obese relative to WT, whereas IFABP−/− mice displayed an opposite, lean phenotype. Fuel utilization followed adiposity, with LFABP−/− mice preferentially utilizing lipids, and IFABP−/− mice preferentially metabolizing carbohydrate for energy production. Changes in body weight and fat may arise, in part, from altered food intake; mucosal levels of the endocannabinoids 2-arachidonoylglycerol and arachidonoylethanolamine were elevated in LFABP−/−, perhaps contributing to increased energy intake. This direct comparison provides evidence that LFABP and IFABP have distinct roles in intestinal lipid metabolism; differential intracellular functions in intestine and in liver, for LFABP−/− mice, result in divergent downstream effects at the systemic level. PMID:23990461

  7. Bombyx mori nucleopolyhedrovirus orf8 encodes a nucleic acid binding protein that colocalizes with IE1 during infection.

    Imai, N; Kurihara, M; Matsumoto, S; Kang, W-K

    2004-08-01

    This report describes the characterization of the Bombyx mori nucleopolyhedrovirus (BmNPV) orf8 gene. Immunoblot analyses demonstrated that orf8 was expressed as an early gene. The ORF8 protein accumulated in the nucleus, and was maintained at relatively constant levels from 4 to 24 h postinfection. Immunoblot analysis failed to detect ORF8 protein associated with budded virus and occlusion derived virus. In addition, immunohistochemical analysis by confocal microscopy showed that ORF8 protein colocalized with IE1 to specific nuclear foci throughout infection. To further examine the function of ORF8, a reporter gene was inserted into the orf8 reading frame. One orf8 disruption mutant (BmD8), which expressed the N-terminal half of ORF8, was isolated. However, it was not possible to isolate a null mutant, suggesting that orf8 may have an important role during viral infection. Single-step growth curves showed that BV production was reduced in BmD8 infected cells. Biochemical analyses indicated that ORF8 bound to nucleic acids. Together, these results suggest that BmNPV ORF8 may be involved in viral DNA replication and/or transcription. PMID:15290382

  8. Inhibitory effects of omega-3 fatty acids on early brain injury after subarachnoid hemorrhage in rats: Possible involvement of G protein-coupled receptor 120/β-arrestin2/TGF-β activated kinase-1 binding protein-1 signaling pathway.

    Yin, Jia; Li, Haiying; Meng, Chengjie; Chen, Dongdong; Chen, Zhouqing; Wang, Yibin; Wang, Zhong; Chen, Gang

    2016-06-01

    Omega-3 fatty acids have been reported to improve neuron functions during aging and in patients affected by mild cognitive impairment, and mediate potent anti-inflammatory via G protein-coupled receptor 120 (GPR120) signal pathway. Neuron dysfunction and inflammatory response also contributed to the progression of subarachnoid hemorrhage (SAH)-induced early brain injury (EBI). This study was to examine the effects of omega-3 fatty acids on SAH-induced EBI. Two weeks before SAH, 30% Omega-3 fatty acids was administered by oral gavage at 1g/kg body weight once every 24h. Specific siRNA for GPR120 was exploited. Terminal deoxynucleotidyl transferase dUTP nick end labeling, fluoro-Jade B staining, and neurobehavioral scores and brain water content test showed that omega-3 fatty acids effectively suppressed SAH-induced brain cell apoptosis and neuronal degradation, behavioral impairment, and brain edema. Western blot, immunoprecipitation, and electrophoretic mobility shift assays results showed that omega-3 fatty acids effectively suppressed SAH-induced elevation of inflammatory factors, including cyclooxygenase-2, monocyte chemoattractant protein-1, and inducible nitric oxide synthase. In addition, omega-3 fatty acids could inhibit phosphorylation of transforming growth factor β activated kinase-1 (TAK1), MEK4, c-Jun N-terminal kinase, and IkappaB kinase as well as activation of nuclear factor kappa B through regulating GPR120/β-arrestin2/TAK1 binding protein-1 pathway. Furthermore, siRNA-induced GPR120 silencing blocked the protective effects of omega-3 fatty acids. Here, we show that stimulation of GPR120 with omega-3 fatty acids pretreatment causes anti-apoptosis and anti-inflammatory effects via β-arrestin2/TAK1 binding protein-1/TAK1 pathway in the brains of SAH rats. Fish omega-3 fatty acids as part of a daily diet may reduce EBI in an experimental rat model of SAH. PMID:27000704

  9. Rapid Diagnosis of acute kidney injury (AKI associated with cardiac surgery, using the liver type fatty acid binding protein (L-FABP biomarker

    Mirbagheri L

    2012-01-01

    Full Text Available Background and objectives: cardiac surgery is often associated with acutekidney injury (AKI. Nowadays, AKI is typically diagnosed by an increase inserum creatinine, which is a delayed and unreliable biomarker. Recent studiesrecommended using the liver type fatty acid binding protein (L-FABP as anearly biomarker.Material and Methods: The urine samples of 18 adult patients undergoingcardiac surgery were collected in different times before (2, 4,8,24 hour andafter cardiac surgery for detection of L-FABP by Elisa.Results: The results from ELISA test show that the increasing amount of LFABPin urine samples of 4 patients is a diagnostic indicator for AKI. Themean concentration of L-FABP has increased up to 17 times at 8 hours aftercardiac surgery compared to before surgery.Conclusion: according to our findings, we speculated that the urinary L-FABPcan be a reliable and rapid biomarker for diagnosis of acute kidney injury.Key words: Acute Kidney Injury, Liver type Fatty Acid Binding Protein,Cardiac surgery

  10. Clinical relevance of drug binding to plasma proteins

    Ascenzi, Paolo; Fanali, Gabriella; Fasano, Mauro; Pallottini, Valentina; Trezza, Viviana

    2014-12-01

    Binding to plasma proteins highly influences drug efficacy, distribution, and disposition. Serum albumin, the most abundant protein in plasma, is a monomeric multi-domain macromolecule that displays an extraordinary ligand binding capacity, providing a depot and carrier for many endogenous and exogenous compounds, such as fatty acids and most acidic drugs. α-1-Acid glycoprotein, the second main plasma protein, is a glycoprotein physiologically involved in the acute phase reaction and is the main carrier for basic and neutral drugs. High- and low-density lipoproteins play a limited role in drug binding and are natural drug delivery system only for few lipophilic drugs or lipid-based formulations. Several factors influence drug binding to plasma proteins, such as pathological conditions, concurrent administration of drugs, sex, and age. Any of these factors, in turn, influences drug efficacy and toxicity. Here, biochemical, biomedical, and biotechnological aspects of drug binding to plasma proteins are reviewed.