Lipid Transfer Proteins

Plant lipid transfer proteins, a widespread family of proteins, have been recently identified as important food allergens. Their common structural features, such as eight conserved cysteines forming disulfide bridges, basic isoelectric point and high similarity in amino acid sequence, are the basis of allergic clinical cross‐reactivity. This has been demonstrated for the LTP allergens of the Prunoideae subfamily, whose similarity is about 95% as demonstrated for the purified allergens of peach, apricot, plum and apple. A relevant aspect is the existence of sequence homology of LTPs of botanically unrelated foods, as demonstrated for LTPs of maize and peach. A class of food allergens of well recognized clinical importance is that of seed storage 2S albumins. They have been identified in the most diffused edible seeds and nuts, such as mustard, sesame, Brazil nut, walnut and peanut. In particular, a strong correlation between IgE‐binding to these proteins and food‐induced anaphylaxis ...

Apolipoprotein E (apoE) enters the plasma as a component of discoidal HDL and is subsequently incorporated into spherical HDL, most of which contain apoE as the sole apolipoprotein. This study investigates the regulation, origins, and structure of spherical, apoE-containing HDLs and their remodeling by cholesteryl ester transfer protein (CETP). When the ability of discoidal reconstituted high density lipoprotein (rHDL) containing apoE2 [(E2)rHDL], apoE3 [(E3)rHDL], or apoE4 [(E4)rHDL] as the sole apolipoprotein to act as substrates for LCAT were compared with that of discoidal rHDL containing apoA-I [(A-I)rHDL], the rate of cholesterol esterification was (A-I)rHDL .. (E2)rHDL z (E3)rHDL . (E4)rHDL. LCAT also had a higher affinity for discoidal (A-I)rHDL than for the apoEcontaining rHDL. When the discoidal rHDLs were incubated with LCAT and LDL, the resulting spherical (E2)rHDL, (E3)rHDL, and (E4)rHDL were larger than, and structurally distinct from, spherical (A-I)rHDL. Incubation of the apoE-containing spherical rHDL with CETP and IntralipidT generated large fusion products without the dissociation of apoE, whereas the spherical (A-I)rHDLs were remodeled into small particles with the formation of lipid-poor apoA-I. In conclusion, i) apoE activates LCAT less efficiently than apoA-I; ii) apoE-containing spherical rHDLs are structurally distinct from spherical (A-I)rHDL; and iii) the CETPmediated remodeling of apoE-containing spherical rHDL differs from that of spherical (A-I)rHDL.-Rye, K-A., R.

Chamaemelum nobile, or Roman chamomile, is a plant containing anti-inflammatory and antimicrobial properties. Antimicrobial peptides (AMPs) are part of the plant defense system including lipid transfer peptides (LPTs). Our objective is to identify a LTP-related protein from C. nobile (cnLTP). PCR was performed on C. nobile DNA for identifying cnLTP gene. Bioinformatics was used for their characterization, and a sensitivity test was carried out on Rhizoctonia solani. cnLTP has 99 amino acids, 9.8 kDa, isoelectric point of 9.39, 33 aliphatic residues, aliphatic index of 85, hydropathicity of 0.127, four alpha-helices and four disulfide bridges. An inhibitory activity of apoplastic fluid of C. nobile was determined at 1 µg/mL on R. solani. This study contributes in the knowledge of a novel and non-characterized LTP using in silico and experimental related approaches.

The understanding of the role of sphingolipid metabolism in cancer has tremendously increased in the past ten years. Many tumors are characterized by imbalances in sphingolipid metabolism. In many cases, disorders of sphingolipid metabolism are also likely to cause or at least promote cancer. In this review, sphingolipid transport proteins and the processes catalyzed by them are regarded as essential components of sphingolipid metabolism. There is much to suggest that these processes are often rate-limiting steps for metabolism of individual sphingolipid species and thus represent potential target structures for pharmaceutical anticancer research. Here, we summarize empirical and biochemical data on different proteins with key roles in sphingolipid transport and their potential role in cancer.

Italian patients with maize anaphylaxis have been shown to have IgE toward two major maize allergens: an alpha-amylase inhibitor and a 9-kDa LTP. A complete study on maize food allergens in patients with positive maize double-blind, placebo-controlled food challenge (DBPCFC) is lacking. The objective was to utilize the three maize protein fractions to identify and characterize the most relevant IgE-binding proteins recognized by the sera of Italian and Swiss patients with either a positive maize-DBPCFC or a history of maizeinduced anaphylaxis. Osborne's protein fractions of maize were extracted to obtain water-soluble, total zein, and total protein fractions. Protein IgE-binding capacity was investigated by SDS-PAGE immunoblotting using the sera from DBPCFC-positive patients and from patients with maize-induced anaphylaxis. Purified maize LTP was used to inhibit the IgE immunoblotting of the three protein fractions. IgE immunoblotting demonstrated that the 9-kDa LTP was recognized by all the Italian patients and by none of the Swiss patients. Other allergens were: 14-kDa α-amylase inhibitor, 30-kDa endochitinases A and -B, 19 kDa zein-β precursor, and 26kDa zein-α precursor; a newly described allergen, the globulin-2 precursor, identified in the total protein fraction. It is noteworthy that maize LTP and endochitinase were cross-reactive with grape LTP and one grape endochitinase. LTP was found to be the only major allergen in Italian patients with either positive maize challenge or a history of maize-induced anaphylaxis. We have identified other maize allergens in subjects with maize food allergy, as grape cross-reactive endochitinase, however, the clinical significance of these proteins needs to be investigated in larger groups of patients with allergy to these food items. Keywords Maize allergens . Grape allergens . Grape crossreactivity . Double-blind placebo-controlled food challenge . Maize anaphylaxis . Lipid transfer proteins . LTP

SUMMARYMembrane contact sites (MCSs) between organelles are heterogeneous in shape, composition and dynamics. Despite this diversity, VAP proteins act as receptors for multiple FFAT motif-containing proteins and drive the formation of most MCSs involving the endoplasmic reticulum (ER). Although the VAP‒FFAT interaction is well characterized, no model explains how VAP adapts to its partners in various MCSs. We report here that VAP-A localization to different MCSs depends on its intrinsically disordered regions (IDRs). We show that VAP-A interaction with PTPIP51 and VPS13A at ER‒mitochondria MCS conditions mitochondria fusion by promoting lipid transfer and cardiolipin buildup. VAP-A also enables lipid exchange at ER‒Golgi MCS by interacting with OSBP and CERT. However, removing IDRs from VAP-A restricts its distribution and function to ER‒ mitochondria MCS, at the expense of ER‒Golgi MCS. Our data suggest that IDRs of VAP-A do not modulate its preference towards specific partners, bu...

A given amino acid sequence can be encoded by a huge number of different nucleic acid sequences. These sequences, however, prove not to be equally useful. The choice of sequence can significantly impact the expression of an encoded protein. As regards the importance of protein-coding sequence and promising industrial and medicinal applications of Clostridium histolyticum collagenase, this study examined the codon optimization of the Col H gene so as to enhance collagenase expression in Escherichia coli (E. coli). The coding region of mature Col H gene was optimized according to the codon usage of E. coli using Gene Designer software (DNA 2.0). The results revealed that relative frequency of codon usage in Col H gene was adapted to the most preferred triplets in E. coli in such a way that codon usage bias in E. coli was enhanced after codon optimization. Similarly, the higher level of collagenase expression was more likely the result of substituting rare codons with optimal codons. A...

Background Plasma cholesteryl ester transfer (CET), reflecting transfer of cholesteryl esters from high density lipoproteins (HDL) towards apolipoprotein B-containing lipoproteins, may promote atherosclerosis development, and is elevated in Type 2 diabetes mellitus (T2DM). We determined the extent to which the relationship of plasma CET with very low density lipoprotein (VLDL) and low density lipoprotein (LDL) subfractions is modified in T2DM. Materials and methods Plasma CET, cholesteryl ester transfer protein (CETP) mass, as well as VLDL and LDL subfractions (nuclear magnetic resonance spectroscopy) were determined in 62 patients with T2DM and 53 nondiabetic subjects. Results Plasma CET and CETP mass were increased in T2DM, coinciding higher triglycerides and large VLDL particles (all P < 0Á02). Plasma CET was positively related to the VLDL and the LDL particle concentration in age-, sex-and diabetes status-adjusted analysis (both P < 0Á001). Multivariable linear regression analysis demonstrated an independent positive interaction between the presence of T2DM and the VLDL concentration on plasma CET (b = 0Á238, P = 0Á033). The relationship of plasma CET with the VLDL concentration was also positively modified by plasma glucose (b = 0Á211, P = 0Á004) and glycated haemoglobin (b = 0Á190, P = 0Á012). Of the individual VLDL subfractions, a positive interaction of diabetes status with large VLDL on plasma CET was observed (b = 0Á280, P = 0Á003). Neither the relationship of the LDL particle concentration nor of CETP mass with plasma CET was modified by the presence of T2DM (P > 0Á15). Conclusion Abnormalities in the concentration and composition of large VLDL particles are likely to contribute to elevated plasma CET in T2DM.

Objective measurement of real-world fall events by using body-worn sensor devices can improve the understanding of falls in older people and enable new technology to prevent, predict, and automatically recognize falls. However, relative to the required recording time, these events are rare and hence challenging to capture. Therefore, the FARSEEING (FAll Repository for the design of Smart and sElf-adapaive Environments prolonging INdependent livinG) consortium and associated partners established a meta-database of signals from real-world falls. Until the end of 2014, 397 falls were measured and reported. This includes falls data from several settings and disease groups, mainly geriatric rehabilitation, Parkinson's disease, cerebellar and sensory ataxia. Seventy-five per cent of the falls were measured with a sampling rate of 100 Hz with devices including at least accelerometers and gyroscopes. To date more than 100 of these real-world falls have been validated and finally processed for data analyses. The observed signal patterns showed a high heterogeneity and differed considerably from those of simulated falls. Preliminary analyses of the available real-world falls data with two different fall-detection approaches using wavelets as well as temporal and mechanical thresholds considerably improved the detection performance. The FARSEEING consortium will continue to increase the number of measured real-world falls in the meta-database beyond the end of the project. External users can request data access on the FARSEEING website.

Elle consomme d'autres variétés d'agrume sans réaction. Les prick-tests (PT) sont réalisés avec le jus, la pulpe et le zeste de citron, orange, pamplemousse, mandarine, yuzu utilisé dans les plats, 2 cultivars de yuzu (B2 et 846), 2 cultivars de mandarine (Citrus mandarina et reticulata), Citrus ichangensis et les aliments consommés lors des repas incriminés. Résultats Les PT sont positifs pour le jus (8 mm) et la pulpe (7 mm) du yuzu utilisé dans la préparation du plat, le jus du Citrus junos B2 (10 mm), le jus (5 mm) et la pulpe (8 mm) du Citrus mandarina. Ils sont négatifs pour les autres agrumes et aliments. La recherche d'IgE spécifiques (ImmunoCap, Thermofisher) aux jus et pulpe de citron, orange, pamplemousse, mandarine, clémentine, thon rouge, rPru p3 est négative. Discussion L'allergie alimentaire aux agrumes est rare en dépit de leur grande consommation. Les cas rapportés concernent principalement l'orange et le citron. Notre patiente présente une allergie alimentaire sélective au yuzu mais peut consommer les autres agrumes. Il est à noter une différence de réactivité entre les différents cultivars de yuzu comme cela est rapporté avec d'autres fruits [1]. Le yuzu B2, qui est la variété la plus consommée, est le plus réactif en test cutané. Déclaration d'intérêts Les auteurs n'ont pas transmis de déclaration de conflits d'intérêts. Références [1] Le TM, Fritsche P, Bublin M, et al. Differences in the allergenicity of 6 different kiwifruit cultivars analyzed by prick-to prick-testing, open food challenges, and Elisa.

Background. Non-specific Lipid Transfer Proteins (nsLTPs) are widely distributed in the plant kingdom and constitute a superfamily of related proteins. More than 800 different sequences have been characterized so far, but their biological functions remain unclear. It has been clear for years that they present a certain interest for agronomic and nutritional issues. Deciphering their functions means collecting and analyzing a variety of data from gene sequence to protein structure, from cellular localization to the physiological role. As a huge and growing number of new protein sequences are available nowadays, extracting meaningful knowledge from sequence-structure-function relationships calls for the development of new tools and approaches. As nsLTPs show high evolutionary divergence, but a conserved common right-handed superhelix structural fold, and as they are involved in a large number of key roles in plant development and defense, they are a stimulating case study for validating such an approach. Methods. In this study, we comprehensively investigated 797 nsLTP protein sequences, including a phylogenetic analysis on canonical protein sequences, three-dimensional (3D) structure modeling and functional annotation using several well-established bioinformatics programs. Additionally, two integrative methodologies using original tools were developed. The first was a new method for the detection of i) conserved amino acid residues involved in structure stabilization and ii) residues potentially involved in ligand interaction. The second was a structure-function classification based on the Evolutionary Trace Display method using a new tree visualization interface. We also present a new tool for visualizing phylogenetic trees. Results. Following this new protocol, an updated classification of the nsLTP superfamily was established and a new functional hypothesis for key residues is suggested. Lastly, this work allows a better representation of the diversity of plant nsLTPs in terms of sequence, structure, and function.

La pêche est un fruit répandu en région méditerranéenne. Il appartient à la famille des Rosacées qui comprend outre les pêches, les pommes, les cerises, les poires, les abricots, les framboises, les fraises, les noisettes et les amandes. Bien que la fréquence réelle de l'allergie à la pêche soit méconnue, cette dernière semble en augmentation. L'allergène majeur est une protéine de transfert lipidique très répandue dans le règne végétal et intervient dans la défense des plantes contre les agressions extérieures. Une allergie croisée avec les autres fruits de la famille des Rosacées et avec les pollens de bouleau et de graminées est fréquente. Nous faisons le point sur cette pathologie à travers l'étude de cinq observations de patients présentant une allergie alimentaire à la pêche ainsi qu'une revue de la littérature.

Background: The cultivation of Bt maize (maize genetically modified with Bacillus thuringiensis) continues to expand globally. Arbuscular mycorrhizal fungi (AMF), a kind of beneficially microbial community, closely related to soil fertility and plant nutrition, may influence the resistance risk of Bt crops against target lepidopteran pests. Methods: In this study, transgenic Bt maize (Line IE09S034 with Cry1Ie vs. its parental line of non-Bt maize cv. Xianyu335) was inoculated with a species of AMF, Glomus caledonium (GC) and its outcomes on the food utilization, reproduction and development of armyworm, Mythimna separata were conducted in a potted experiment from 2017 to 2018. Results: AMF inoculation showed favorable influence on the GC colonization of both modified and non-modified maize, and marked increase in the grain weight per plant and 1000-grain weight of modified and non-modified maize. Meanwhile, the cultivation of Bt maize didn’t significantly affected the AMF colonizat...

Movement in proteins requires energy. To this end, natural selection has selected phosphate as the principal energy currency in cells. On the other hand, depicting the state of transcription could come in the form of epigenetic markers, which are modifications on nucleotide residues. But, what are the deeper evolutionary forces that underpin the selection of phosphorylation as a key process for translating molecular information of cellular state into specific phenotype in movement and metabolism at the cellular level? From another perspective, what are the factors that guide the selection of particular phosphosites as principal phosphorylation sites? Seeking answers to the latter question, Villen and coworkers (“Evolution of protein phosphorylation across 18 fungal species”, Science, Link ) used mass spectrometry to profile the phosphoproteome of 18 fungal species and employed discovery science approaches to elucidate specific phosphosite highly conserved for particular functions su...

The immune checkpoint plays an important role in keeping immune cells in check for protecting tissues and organs from attack by the body’s own immune system. Similar concepts also apply in how cancer cells managed to fool immune cells through the surface display of particular antigens that mimic those exhibited by normal body cells. Specifically, cancer cells display antigens that bind to receptors on immune cells that subsequently prevent an attack on the cancer cells. Such binding between cancer antigens and immune cell receptors can be prevented through the use of checkpoint inhibitors antibodies specific for particular receptors on immune cells; thereby, unleashing immune cells to mount an immune response against cancer cells. While demonstrating good remissions in many patients where tumours shrunk substantially after administration of checkpoint inhibitors, cases exist where an overactivated immune system cause harm to organs and tissues culminating in multiple organ failure. ...

Bacterial cells utilize a variety of nanomachines to secrete proteins and other molecules into the extracellular environment or target cells. One example is the Type VI secretion system (T6SS) in Gram-negative bacteria. Armed with a contractile mechanism similar to that used by bacteriophages to inject phage DNA into bacterial cells, the T6SS shares a common evolutionary origin with tail associated proteins of bacteriophages at both the structural and protein composition levels. Specifically, proteins constituting the T6SS are known to share provenance with those of the phage tail protein. More importantly, the T6SS is strikingly similar to the phage tail protein in both structure and function. However, a more important question concerns whether the T6SS evolved from the phage tail protein and if yes, what is the mechanism responsible for its development? One possibility could be the co-opt of the tail protein structure by bacterial cells through integration of the genes encoding th...

FASTA file format is a common file type for distributing proteome information, especially those obtained from Uniprot. While MATLAB could automatically read fasta files using the built-in function, fastaread, important information such as protein name and organism name remain enmeshed in a character array. Hence, difficulty exists in automatic extraction of protein names from fasta proteome file to help in building a database with fields comprising protein name and its amino acid sequence. The objective of this work was in developing a MATLAB software that could automatically extract protein name and amino acid sequence information from fasta proteome file and assign them to a new database that comprises fields such as protein name, amino acid sequence, number of amino acid residues, molecular weight of protein and nucleotide sequence of protein. Information on number of amino acid residues came from the use of the length built-in function in MATLAB analyzing the length of the amino...

Gram-negative bacteria such as Escherichia coli and Salmonella enterica possess two phospholipid bilayer membranes in the cell envelope. Known as the inner and outer membrane, proteins encased in the outer membrane as well as surface moieties displayed by the membrane play important roles in host-cell recognition, cell-cell interactions and triggering of immune response in host. One such molecule that partakes in triggering immune responses in human is lipopolysaccharides that constitute the outer leaflet of the outer membrane of Gram-negative bacteria. Specifically, recent research has added new details and mechanisms for the elaborate choreographed enzymatic reactions that synthesize lipopolysaccharides. In particular, lipopolysaccharides are synthesized in the inner membrane and transported to the outer membrane through a dedicated protein channel formed by proteins of the same lipopolysaccharide synthesis pathway. In short, significant amount of proteins and cellular resources a...

Different microbes grow at different optimal growth temperature. But, what defines this metabolic adaptation at the molecular and genetic level? And, more importantly, how different metabolic and signalling networks interact to yield a cellular system able to achieve maximal growth rate at a specific temperature? Molecular knowledge of such interacting components could provide a template on which modifications could be made to help adapt a microbe to another optimal growth temperature. However, given the large number of genes, proteins and pathways involved, efforts to re-adapt a microbe to another optimal growth temperature is likely difficult through a rational design approach. On the other hand, laboratory evolution approach might do the trick, but significant efforts are needed to understand the biochemical and physiological logic of the re-adaption. Using the genetically tractable Escherichia coli as model organism, this work aims to explore the possibility of using a rational ...

Ribosomes are highly conserved macromolecular machines whose critical function is protein synthesis. However, existence of unique molecular mass of the same type of ribosomal protein for individual species in the same domain of life raises the interesting question concerning the interaction between natural selection forces and the conservation of structure and function of ribosomal proteins. Thus, given differentiated molecular mass and sequence of ribosomal proteins across species, the structures of ribosomes are correspondingly differentiated even though the general structure and function of the macromolecular machine is conserved across species in the same domain of life. The collection of molecular mass of all ribosomal proteins in the large and small ribosome subunits can be understood as the ribosomal protein mass fingerprint of the species useful for gaining fundamental knowledge of ribosomal proteins, as well as serving as tools for species identification through comparison ...

Background: Glioblastoma multiforme (GBM) is a grade IV brain tumor that arises from star-shaped glial cells supporting neural cells called astrocytes. The survival of GBM patients remains poor despite many specific molecular targets that have been developed and used for therapy. Tousled-like kinase 1 (TLK1), a serine-threonine kinase, was identified to be overexpressed in cancers such as GBM. TLK1 plays an important role in controlling chromosomal aggregation, cell survival and proliferation. In vitro studies suggested that TLK1 is a potential target for some cancers; hence, the identification of suitable molecular inhibitors for TLK1 is warranted as a new therapeutic agents in GBM. To date, there is no structure available for TLK1. In this study, we aimed to create a homology model of TLK1 and to identify suitable molecular inhibitors or compounds that are likely to bind and inhibit TLK1 activity via in silico high-throughput virtual screening (HTVS) protein-ligand docking. Method...

Alternative splicing enables a single gene to produce multiple mRNA isoforms by varying splice site selection. In animals, alternative splicing of mRNA isoforms between cell types is widespread and supports cellular differentiation. In plants, at least 20% of multi-exon genes are alternatively spliced, but the extent and significance of tissue-specific splicing is less well understood, partly because it is difficult to isolate cells of a single type. Pollen is a useful model system to study tissue-specific splicing in higher plants because pollen grains contain only two cell types and can be collected in large amounts without damaging cells. Previously, we identified pollen-specific splicing patterns by comparing RNA-Seq data from Arabidopsis pollen and leaves. Here, we used semi-quantitative PCR to validate pollenspecific splicing patterns among genes where RNA-Seq data analysis indicated splicing was most different between pollen and leaves. PCR testing confirmed eight of nine alternative splicing patterns, and results from the ninth were inconclusive. In four genes, alternative transcriptional start sites coincided with alternative splicing. This study highlights the value of the low-cost PCR assay as a method of validating RNA-Seq results.

Italian patients with maize anaphylaxis have been shown to have IgE toward two major maize allergens: an alpha-amylase inhibitor and a 9-kDa LTP. A complete study on maize food allergens in patients with positive maize double-blind, placebo-controlled food challenge (DBPCFC) is lacking. The objective was to utilize the three maize protein fractions to identify and characterize the most relevant IgE-binding proteins recognized by the sera of Italian and Swiss patients with either a positive maize-DBPCFC or a history of maizeinduced anaphylaxis. Osborne's protein fractions of maize were extracted to obtain water-soluble, total zein, and total protein fractions. Protein IgE-binding capacity was investigated by SDS-PAGE immunoblotting using the sera from DBPCFC-positive patients and from patients with maize-induced anaphylaxis. Purified maize LTP was used to inhibit the IgE immunoblotting of the three protein fractions. IgE immunoblotting demonstrated that the 9-kDa LTP was recognized by all the Italian patients and by none of the Swiss patients. Other allergens were: 14-kDa α-amylase inhibitor, 30-kDa endochitinases A and-B, 19 kDa zein-β precursor, and 26kDa zein-α precursor; a newly described allergen, the globulin-2 precursor, identified in the total protein fraction. It is noteworthy that maize LTP and endochitinase were cross-reactive with grape LTP and one grape endochitinase. LTP was found to be the only major allergen in Italian patients with either positive maize challenge or a history of maize-induced anaphylaxis. We have identified other maize allergens in subjects with maize food allergy, as grape cross-reactive endochitinase, however, the clinical significance of these proteins needs to be investigated in larger groups of patients with allergy to these food items. Keywords Maize allergens. Grape allergens. Grape crossreactivity. Double-blind placebo-controlled food challenge. Maize anaphylaxis. Lipid transfer proteins. LTP

Le diagnostic d'allergie alimentaire à la noisette a récemment bénéficié des dosages sériques d'IgE spécifiques vis-à-vis des fractions Cor a 1 et Cor a 8 dont la présence orienterait vers la bénignité pour la fraction Cor a 1 et la gravité pour la fraction Cor a 8. Nous rapportons quatre cas pour lesquels cette notion est contredite. Le test de provocation oral (TPO) à la noisette a provoqué des réactions cliniques importantes chez ces enfants, et une forte augmentation de la tryptasémie au terme du TPO. Le dosage sérique d'IgE spécifiques recombinantes vis-à-vis de la fraction Cor a8 était négatif (ou très bas). Celui de la fraction recombinante Cor a 1 était soit très élevé, soit bas. Nous discutons la pertinence clinique de cet aphorisme répandu (Cor a 1 = bénignité ; Cor a 8 = gravité), dont l'application doit être modulée pour la pratique clinique. D'autres fractions allergéniques pourraient rendre compte de ces observations.

Up to the present, only one major allergen had been univocally identified by chemical analysis (N-terminal sequencing) in the salt-extractable (cytoplasmic) protein fraction of maize kernels (Zea mays): the lipid transfer protein (Pastorello et al., Allergy Clin. Immunol. 2000;106:744-751). In the present study, two-dimensional maps of kernel flour have been set up, the proteins transferred to nitrocellulose membranes and confronted with sera of various patients allergic to maize proteins. Via spot excision and Orbitrap mass analysis, the following new allergens have been identified: vicilin, globulin-2, 50 kDa gamma-zein, endochitinase, thioredoxin and trypsin inhibitor. Vicilin was found to be composed of a string of six spots, all of them allergenic; also globulin-2 was composed of a string of five spots, exhibiting equivalent allergenicity. The 50 kDa gamma-zein, found here in the maize flour soluble fraction, is identical to the 50 kDa allergen reported by Pasini et al. (Allergy 2002; 57:98-106), but present in the insoluble fraction and solubilized via-S-S-reducing agents. However, the form here described might be a truncated species, since it exhibits an apparent Mr, in SDS-PAGE, of ca. 35 kDa. The homology of three of them (vicilin, globulin-2 and thioredoxin) with other vegetable systems has been investigated via BLAST analysis, the ones with highest homology belonging to rice, wheat and barley. The present data add a non-negligible amount of previously unreported allergens to the scanty panorama of maize proteins.

Background: Glioblastoma multiforme (GBM) is a grade IV brain tumor that arises from star-shaped glial cells supporting neural cells called astrocytes. The survival of GBM patients remains poor despite many specific molecular targets that have been developed and used for therapy. Tousled-like kinase 1 (TLK1), a serine-threonine kinase, was identified to be overexpressed in cancers such as GBM. TLK1 plays an important role in controlling chromosomal aggregation, cell survival and proliferation. In vitro studies suggested that TLK1 is a potential target for some cancers; hence, the identification of suitable molecular inhibitors for TLK1 is warranted as a new therapeutic agents in GBM. To date, there is no structure available for TLK1. In this study, we aimed to create a homology model of TLK1 and to identify suitable molecular inhibitors or compounds that are likely to bind and inhibit TLK1 activity via in silico high-throughput virtual screening (HTVS) protein-ligand docking. Method...

Lipid membranes are found in most intracellular organelles, and their heterogeneities play an essential role in regulating the organelles’ biochemical functionalities. Here we report a Spectrum and Polarization Optical Tomography (SPOT) technique to study the subcellular lipidomics in live cells. Simply using one dye that universally stains the lipid membranes, SPOT can simultaneously resolve the membrane morphology, polarity, and phase from the three optical-dimensions of intensity, spectrum, and polarization, respectively. These high-throughput optical properties reveal lipid heterogeneities of ten subcellular compartments, at different developmental stages, and even within the same organelle. Furthermore, we obtain real-time monitoring of the multi-organelle interactive activities of cell division and successfully reveal their sophisticated lipid dynamics during the plasma membrane separation, tunneling nanotubules formation, and mitochondrial cristae dissociation. This work sugg...

Eukaryotic cells have regions of interaction between two organelles where some proteins, which act as tether, bring both membranes closer (10-30 nm) without fusion, named membrane contact sites (MCS). Two organelles that can form MCS are endoplasmic reticulum (ER) and plasma membrane (PM). ER-PM CS play important metabolic functions such as communication between both membranes, lipid homeostasis and Ca 2+ influx. Our group has identified that AtDGK1 and AtDGK2 (Diacylglycerol kinase 1, AT5G07920 and Diacylglycerol kinase 2, At5g63770) form a complex with a well-known protein located at ER-PM CS, Synaptotagmin1 (SYT1, At2g20990). Upon perception of stress, phospholipase C (PLC) is activated at the plasma membrane to hydrolyse PIP(4,5)P2 or PI4P in order to generate DAG and inositol phosphates. Diacylglycerol (DAG) is phosphorylated by diacylglycerol kinases (DGKs) to produce phosphatidic acid (PA). DAG and PA are important cell signalling molecules. There are seven DGKs encoded in Arabidopsis thaliana genome, but only DGK1 and DGK2 have a transmembrane domain that anchors them to the endoplasmic reticulum, the rest are cytoplasmic. DGK1 and DGK2 appear to play a role in stress response as both are induced by exposure to low temperatures and wounding. Also, we found that dgk2 knockout mutant produces lower resistance to freezing. Using confocal microscopy, we have analysed the subcellular localization of these two proteins and investigated their interaction with SYT1 and between them using FRET and co-immunoprecipitation studies. Additionally, we report that the mutation of DGK1 is lethal in homozygosity. Our studies suggest that DGK1 and DGK2 act in concert with SYT1 to regulate the production of PA at ER-PM CS and highlight the importance of these proteins for the correct response to stress tolerance.

Nodulated bean plants were exposed to mild salt stress or water deficit in such a way that the nodule's nitrogen-fixing activity was reduced to about 25-30% that of controls. Water-deprived plants showed a slight decrease in the weight of the aerial part, whereas the photosynthetic parameters were not significantly affected. In contrast, saltstressed plants displayed a reversible decrease in the quantum yield of photosystem II photochemistry. Five waterdeficit responsive cDNA clones encoding one lipid transfer protein, two late-embryogenesis abundant (LEA) proteins and two proline-rich proteins (PRPs) showed different organ-specific expression patterns depending on the kind of stress applied. PRPs and one LEA protein, PvLEA-18, exhibited the highest expression in nodules. Anti-PvLEA-18 antibodies were used to immunolocalize the protein in the nodule. PvLEA-18 was localized in the cytoplasm and nucleus of nodule cortex cells, and preferentially in cells of the vascular bundles, showing enhanced accumulation under water deficit. To our knowledge, this is the first time that a LEA protein has been identified in legume nodules.

Nodulated bean plants were exposed to mild salt stress or water deficit in such a way that the nodule's nitrogen-fixing activity was reduced to about 25-30% that of controls. Water-deprived plants showed a slight decrease in the weight of the aerial part, whereas the photosynthetic parameters were not significantly affected. In contrast, saltstressed plants displayed a reversible decrease in the quantum yield of photosystem II photochemistry. Five waterdeficit responsive cDNA clones encoding one lipid transfer protein, two late-embryogenesis abundant (LEA) proteins and two proline-rich proteins (PRPs) showed different organ-specific expression patterns depending on the kind of stress applied. PRPs and one LEA protein, PvLEA-18, exhibited the highest expression in nodules. Anti-PvLEA-18 antibodies were used to immunolocalize the protein in the nodule. PvLEA-18 was localized in the cytoplasm and nucleus of nodule cortex cells, and preferentially in cells of the vascular bundles, showing enhanced accumulation under water deficit. To our knowledge, this is the first time that a LEA protein has been identified in legume nodules.

Peptides fulfill a plethora of functions in plant growth, development, and stress responses. They act as key components of cell-to-cell communication, interfere with signaling and response pathways, or display antimicrobial activity. Strikingly, both the diversity and amount of plant peptides have been largely underestimated. Most characterized plant peptides to date acting as small signaling peptides or antimicrobial peptides are derived from nonfunctional precursor proteins. However, evidence is emerging on peptides derived from a functional protein, directly translated from small open reading frames (without the involvement of a precursor) or even encoded by primary transcripts of microRNAs. These novel types of peptides further add to the complexity of the plant peptidome, even though their number is still limited and functional characterization as well as translational evidence are often controversial. Here, we provide a comprehensive overview of the reported types of plant pep...

Background: Arterial thrombosis causes heart attacks and strokes and constitutes one of the leading causes of morbidity and mortality in the world and few therapies are available for its treatment. Thus, new therapeutic approaches in the prevention and treatment of arterial thrombosis are needed. Protein disulfide isomerase (PDI) has been shown to be expressed on vascular cells following injury and to be involved in regulating thrombus formation in vivo. Since inhibition of PDI prevents platelet accumulation and fibrin generation, it makes it a valuable target for the development of new antithrombotics. Rutin, a flavonol glycoside derivative of Quercetin, was previously described for displaying decent potency against PDI, and it inhibited the agonist-induced platelets aggregation in vivo, however its utility is limited by its low solubility and its off-target activity. Rutin was recently reported to bind specifically to the b’ domain of PDI affecting protein flexibility which result...

Here, we present the proteome profiling of low-molecular weight (< 50 kDa) proteins of seven different lentil cultivars developed by Bangladesh Agricultural Research Institute. A total of 2873 peptides corresponding to 180 unique proteins were identified wherein > 24% of them were described lentil allergens. Comparative relative quantitation showed differences in protein abundance of major allergen proteins such as Len c 1.0101, Len c 1.0102, and lipid transfer proteins (LTPs), indicating qualitative and quantitative variations in allergen proteins in lentil cultivars. In this report, for the first-time, the amino acid sequence of LTPs in lentil has been confirmed by high resolution mass spectrometry. In addition, ideal peptides of Len c 1.0101, Len c 1.0102, and LTPs allergens were further determined with multiple reaction monitoring (MRM) analysis. Therefore, this data could provide a great resource for further development of targeted, proteomics-based assays for quantification of lentil allergens.

Wheat beer is a traditional light coloured top-fermenting beer brewed with at least 50% of malted (e.g. German Weissbier) or unmalted (e.g. Belgian Witbier) wheat (Triticum aestivum) as adjunct to barley (Hordeum vulgare) malt. For the first time we explored the proteome of three Weissbier samples, using both two-dimensional electrophoresis (2DE)-based and 2DE-free strategies. Overall, 58 different gene products arising from barley, wheat and yeast (Saccharomyces spp.) were identified in the protein fraction of a representative Weissbier sample analyzed in detail. Analogously to all barley malt beers (BMB), barley and wheat Z-type serpins and non-specific lipid transfer proteins dominated the proteome of Weissbier. Several -amylase/trypsin inhibitors also survived the harsh brewing conditions. During brewing, hundreds of peptides are released into beer. By liquid chromatography-electrospray tandem mass spectrometry (LC-ESI MS/MS), we characterized 167 peptides belonging to 44 prote...

Background: Glioblastoma multiforme (GBM) is a grade IV brain tumor that arises from star-shaped glial cells supporting neural cells called astrocytes. The survival of GBM patients remains poor despite many specific molecular targets that have been developed and used for therapy. Tousled-like kinase 1 (TLK1), a serine-threonine kinase, was identified to be overexpressed in cancers such as GBM. TLK1 plays an important role in controlling chromosomal aggregation, cell survival and proliferation. In vitro studies suggested that TLK1 is a potential target for some cancers; hence, the identification of suitable molecular inhibitors for TLK1 is warranted as a new therapeutic agents in GBM. To date, there is no structure available for TLK1. In this study, we aimed to create a homology model of TLK1 and to identify suitable molecular inhibitors or compounds that are likely to bind and inhibit TLK1 activity via in silico high-throughput virtual screening (HTVS) protein-ligand docking. Method...

Le syndrome oral est une manifestation fréquente de l'allergie alimentaire aux rosacées s'intégrant plus largement dans une allergie croisée avec le bouleau. Jusqu'à aujourd'hui, le traitement reposait sur une éviction totale de ces fruits crus. Nous présentons ici une nouvelle approche thérapeutique, permettant d'initier une induction de tolérance orale (ITO) aux rosacées chez l'adulte et l'enfant par l'intermédiaire de la pomme « Golden » crue avec la peau mise en place dans le service d'allergologie de l'hôpital Lyon-Sud et les résultats d'une étude réalisée grâce à cette technique portant sur 52 patients effectuées par des allergologues de ville formés à cette technique.

The technology of docking molecules in-silico has evolved significantly in recent years and has become a crucial component of the drug discovery tool process that includes virtual screening, lead optimization, and side-effect predictions. To date over 43,000 abstracts/papers have been published on docking, thereby highlighting the importance of this computational approach in the context of drug development. Considering the large amount of genomic and proteomic consortia active in the public domain, docking can exploit this data on a correspondingly ‘large scale’ to address a variety of research questions. Over 160 robust and accurate molecular docking tools based on different algorithms have been made available to users across the world. Further, 109 scoring functions have been reported in the literature till date. Despite these advancements, there continue to be several bottlenecks during the implementation stage. These problems or issues range from choosing the right docking algor...

Polyamines (PAs) are natural aliphatic amines involved in many physiological processes in almost all living organisms, including responses to abiotic stresses and microbial interactions. This review presents the profuse evidence that relates changes in polyamines levels during responses to biotic and abiotic stresses in model and cultivable species within Leguminosae, and examines their potential roles in the functioning of symbiotic interactions with nitrogen fixing bacteria and arbuscular mycorrhizae. The family Leguminosae constitutes an economically and ecologically key botanical group for humans, being also regarded as the most important protein source for livestock. The ability of legumes to establish symbiotic interactions with nitrogen fixing bacteria and arbuscular mycorrhizae fungi, gives to some legume species that are able to exploit their molecular machinery “pioneer” attributes, with better competition in nutrient-poor soils and higher adaptation to restricted environm...

Eukaryotic cells are characterized by their exquisite compartmentalization resulting from a cornucopia of membrane-bound organelles. Each of these compartments hosts a flurry of biochemical reactions and supports biological functions such as genome storage, membrane protein and lipid biosynthesis/degradation and ATP synthesis, all essential to cellular life. Acting as hubs for the transfer of matter and signals between organelles and throughout the cell, membrane contacts sites (MCSs), sites of close apposition between membranes from different organelles, are essential to cellular homeostasis. One of the now well-acknowledged function of MCSs involves the non-vesicular trafficking of lipids; its characterization answered one long-standing question of eukaryotic cell biology revealing how some organelles receive and distribute their membrane lipids in absence of vesicular trafficking. The endoplasmic reticulum (ER) in synergy with the mitochondria, stands as the nexus for the biosynthesis and distribution of phospholipids (PLs) throughout the cell by contacting nearly all other organelle types. MCSs create and maintain lipid fluxes and gradients essential to the functional asymmetry and polarity of biological membranes throughout the cell. Membrane apposition is mediated by proteinaceous tethers some of which function as lipid transfer proteins (LTPs). We summarize here the current state of mechanistic knowledge of some of the major classes of LTPs and tethers based on the available atomic to near-atomic resolution structures of several "model" MCSs from yeast but also in Metazoans; we describe different models of lipid transfer at MCSs and analyze the determinants of their specificity and directionality. Each of these systems illustrate fundamental principles and mechanisms for the non-vesicular exchange of lipids between eukaryotic membrane-bound organelles essential to a wide range of cellular processes such as at PL biosynthesis and distribution, lipid storage, autophagy and organelle biogenesis.

Background: The cultivation of Bt maize (maize genetically modified with Bacillus thuringiensis) continues to expand globally. Arbuscular mycorrhizal fungi (AMF), a kind of beneficially microbial community, closely related to soil fertility and plant nutrition, may influence the resistance risk of Bt crops against target lepidopteran pests. Methods: In this study, transgenic Bt maize (Line IE09S034 with Cry1Ie vs. its parental line of non-Bt maize cv. Xianyu335) was inoculated with a species of AMF, Glomus caledonium (GC) and its outcomes on the food utilization, reproduction and development of armyworm, Mythimna separata were conducted in a potted experiment from 2017 to 2018. Results: AMF inoculation showed favorable influence on the GC colonization of both modified and non-modified maize, and marked increase in the grain weight per plant and 1000-grain weight of modified and non-modified maize. Meanwhile, the cultivation of Bt maize didn’t significantly affected the AMF colonizat...

Background: Allergy to Prunoideae fruit (plum, peach, cherry and apricot) is one of the most frequent food allergies in southern Europe. All these fruits cross-react in vivo and in vitro, as they share their major allergen, a 9 kD lipid transfer protein (LTP). Objective: The aim of the study was the identification and molecular characterization of the major allergen of plum. Methods: The IgE pattern of reactivity to plums was investigated by SDS-PAGE and immunoblotting with the sera of 23 patients. The identified major allergen was purified by HPLC, using a cationic-exchange column followed by gel-filtration. Further characterization was achieved by periodic-Schiff stain, isoelectrofocusing and N-terminal amino acid sequencing. Results and conclusions: The major allergen of plum is a 9 kD lipid transfer protein, not glycosylated and with a basic character (pI.9), highly homologous to the major allergen of peach.

Background: Allergy to apple is commonly associated with birch pollinosis because the two share homologous allergens. However, some patients have apple allergy but no birch pollinosis, suggesting that there are allergens that do not crossreact with birch. Objective: The aim of the study was to evaluate the IgE reactivity pattern to an apple extract in subjects with allergic reactions to apple, with and without birch hay fever. Methods: Forty-three patients with oral allergy syndrome for apple and positive open food challenge, skin prick test, and serum specific IgE antibodies to apple were admitted to the study. Thirty-two had birch pollinosis (documented by specific IgE for birch) and 11 were not allergic to birch. The IgE reactivity pattern to apple extract was identified by SDS-PAGE and immunoblotting. The consistent allergen, a 9-kd protein, was then purified by HPLC and characterized by periodic acid-Schiff staining, isoelectric point, and N-terminal amino acid sequencing. Results: The sera from 28% of patients allergic to apple with birch pollinosis, but from all patients allergic only to apple, recognized the 9-kd protein. This protein has an isoelectric point of 7.5 and is not glycosylated. Determination of its partial amino acid sequence showed that it belongs to the family of lipid transfer proteins, which act as major allergens in Prunoideae fruits. Conclusions: These results indicate that a lipid transfer protein is an important allergen in patients allergic to apple but not to birch pollen. The prevalent IgE reactivity to this allergen in subjects with no birch pollinosis and the physicochemical characteristics of this protein suggest that sensitization may occur through the oral route. (J Allergy Clin Immunol 1999;104:1099-106.)