Extracellular aspartic protease SAP2 of Candida albicans yeast cleaves human kininogens and releases proinflammatory peptides, Met-Lys-bradykinin and des-Arg(9)-Met-Lys-bradykinin

Bradykinin-related peptides, universal mediators of inflammation collectively referred to as the kinins, are often produced in excessive amounts during microbial infections. We have recently shown that the yeast Candida albicans, the major fungal pathogen to humans, can exploit two mechanisms to enhance kinin levels at the sites of candidial infection, one depending on adsorption and activation of the endogenous kinin-generating system of the host on the fungal cell wall and the other relying on cleavage of kinin precursors, the kininogens, by pathogen-secreted proteases. This work aimed at assigning this kininogenase activity to the major secreted aspartic protease of C. albicans (SAP2). The purified SAP2 was shown to cleave human kininogens, preferably the low molecular mass form (LK) and optimally in an acidic environment (pH 3.5-4.0), and to produce two kinins, Met-Lys-bradykinin and its derivative, {[}Hydroxyproline(3)]-Met-Lys-bradykinin, both of which are capable of interacting with cellular bradykinin receptors of the B2 subtype. Additionally, albeit with a lower yield, des-Arg(9)-Met-Lys-bradykinin, an effective agonist of B1-subtype receptors, was released. The pathophysiological potential of these kinins and des-Arg-kinin was also proven by presenting their ability to stimulate human promonocytic cells U937 to release proinflammatory interleukin 1 beta (IL-1 beta) and IL-6

Kinin-generating cellular model obtained from human glioblastoma cell line U-373

Kinins, a group of important pro-inflammatory peptides, are abundantly found in tissues and biological fluids of cancer patients. Bradykinin, the major representative of kinins, induces vascular permeability and, in consequence, promotes tumor expansion. Additionally, the kinin-induced inflammatory responses, especially those mediated by kinin metabolites without the C-terminal arginine residue, lead to enhanced tumor growth. The present study aimed at analyzing the ability of the human glioblastoma cell line U-373, derived from a malignant tumor, to produce kinin peptides. The proteins involved in kinin generation, i.e., the kininogens and the kallikreins, were shown to be expressed in these cells. Moreover, tumor necrosis factor α, a proinflammatory cytokine that mediates tumorigenesis, was found to enhance the expression of enzymes associated with kinin production. The strong binding of kininogen to the cell surface and the enzymatic degradation of this protein by cells suggest the activation of kinin-generating systems. Indeed, glioblastoma cells, pre-treated with tumor necrosis factor α, released kinin peptides from exogenous kininogen. The expression of kinin receptors in these cells was also shown to increase under the influence of this cytokine. Our results suggest that the human glioblastoma cell line U-373 constitutes a good cellular model that can be helpful in cancer research focused on kinin-induced inflammation. Furthermore, our findings can contribute to new approaches in cancer treatment with the use of kinin receptor antagonists and inhibitors of kinin production

DiagHunter and GenoPix2D: programs for genomic comparisons, large-scale homology discovery and visualization

The DiagHunter and GenoPix2D applications work together to enable genomic comparisons and exploration at both genome-wide and single-gene scales. DiagHunter identifies homologous regions (synteny blocks) within or between genomes. DiagHunter works efficiently with diverse, large datasets to predict extended and interrupted synteny blocks and to generate graphical and text output quickly. GenoPix2D allows interactive display of synteny blocks and other genomic features, as well as querying by annotation and by sequence similarity

An Ultra-High-Density, Transcript-Based, Genetic Map of Lettuce.

We have generated an ultra-high-density genetic map for lettuce, an economically important member of the Compositae, consisting of 12,842 unigenes (13,943 markers) mapped in 3696 genetic bins distributed over nine chromosomal linkage groups. Genomic DNA was hybridized to a custom Affymetrix oligonucleotide array containing 6.4 million features representing 35,628 unigenes of Lactuca spp. Segregation of single-position polymorphisms was analyzed using 213 F7:8 recombinant inbred lines that had been generated by crossing cultivated Lactuca sativa cv. Salinas and L. serriola acc. US96UC23, the wild progenitor species of L. sativa The high level of replication of each allele in the recombinant inbred lines was exploited to identify single-position polymorphisms that were assigned to parental haplotypes. Marker information has been made available using GBrowse to facilitate access to the map. This map has been anchored to the previously published integrated map of lettuce providing candidate genes for multiple phenotypes. The high density of markers achieved in this ultradense map allowed syntenic studies between lettuce and Vitis vinifera as well as other plant species

The low-temperature sol-gel synthesis of metal-oxide films on polymer substrates and the determination of their optical and dielectric properties

Photoactive, optically transparent heterostructures from silver nanowires and titanium dioxide were obtained by the sol-gel method on the surface of a polyethylene terephthalate film. The characteristics of optical transmission on the wavelength and those of dielectric permittivity, conductivity and dissipation on frequency in the range of 25–1,000,000 Hz were investigated

Global expression analysis of nucleotide binding site-leucine rich repeat-encoding and related genes in Arabidopsis

<p>Abstract</p> <p>Background</p> <p>Nucleotide binding site-leucine rich repeat (NBS-LRR)-encoding genes comprise the largest class of plant disease resistance genes. The 149 NBS-LRR-encoding genes and the 58 related genes that do not encode LRRs represent approximately 0.8% of all ORFs so far annotated in Arabidopsis ecotype Col-0. Despite their prevalence in the genome and functional importance, there was little information regarding expression of these genes.</p> <p>Results</p> <p>We analyzed the expression patterns of ~170 NBS-LRR-encoding and related genes in Arabidopsis Col-0 using multiple analytical approaches: expressed sequenced tag (EST) representation, massively parallel signature sequencing (MPSS), microarray analysis, rapid amplification of cDNA ends (RACE) PCR, and gene trap lines. Most of these genes were expressed at low levels with a variety of tissue specificities. Expression was detected by at least one approach for all but 10 of these genes. The expression of some but not the majority of NBS-LRR-encoding and related genes was affected by salicylic acid (SA) treatment; the response to SA varied among different accessions. An analysis of previously published microarray data indicated that ten NBS-LRR-encoding and related genes exhibited increased expression in wild-type Landsberg <it>erecta </it>(L<it>er</it>) after flagellin treatment. Several of these ten genes also showed altered expression after SA treatment, consistent with the regulation of <it>R </it>gene expression during defense responses and overlap between the basal defense response and salicylic acid signaling pathways. Enhancer trap analysis indicated that neither jasmonic acid nor benzothiadiazole (BTH), a salicylic acid analog, induced detectable expression of the five NBS-LRR-encoding genes and one TIR-NBS-encoding gene tested; however, BTH did induce detectable expression of the other TIR-NBS-encoding gene analyzed. Evidence for alternative mRNA polyadenylation sites was observed for many of the tested genes. Evidence for alternative splicing was found for at least 12 genes, 11 of which encode TIR-NBS-LRR proteins. There was no obvious correlation between expression pattern, phylogenetic relationship or genomic location of the NBS-LRR-encoding and related genes studied.</p> <p>Conclusion</p> <p>Transcripts of many NBS-LRR-encoding and related genes were defined. Most were present at low levels and exhibited tissue-specific expression patterns. Expression data are consistent with most Arabidopsis NBS-LRR-encoding and related genes functioning in plant defense responses but do not preclude other biological roles.</p

Sampling nucleotide diversity in cotton

<p>Abstract</p> <p>Background</p> <p>Cultivated cotton is an annual fiber crop derived mainly from two perennial species, <it>Gossypium hirsutum </it>L. or upland cotton, and <it>G. barbadense </it>L., extra long-staple fiber Pima or Egyptian cotton. These two cultivated species are among five allotetraploid species presumably derived monophyletically between <it>G. arboreum </it>and <it>G. raimondii</it>. Genomic-based approaches have been hindered by the limited variation within species. Yet, population-based methods are being used for genome-wide introgression of novel alleles from <it>G. mustelinum </it>and <it>G. tomentosum </it>into <it>G. hirsutum </it>using combinations of backcrossing, selfing, and inter-mating. Recombinant inbred line populations between genetics standards TM-1, (<it>G. hirsutum</it>) × 3-79 (<it>G. barbadense</it>) have been developed to allow high-density genetic mapping of traits.</p> <p>Results</p> <p>This paper describes a strategy to efficiently characterize genomic variation (SNPs and indels) within and among cotton species. Over 1000 SNPs from 270 loci and 279 indels from 92 loci segregating in <it>G. hirsutum </it>and <it>G. barbadense </it>were genotyped across a standard panel of 24 lines, 16 of which are elite cotton breeding lines and 8 mapping parents of populations from six cotton species. Over 200 loci were genetically mapped in a core mapping population derived from TM-1 and 3-79 and in <it>G. hirsutum </it>breeding germplasm.</p> <p>Conclusion</p> <p>In this research, SNP and indel diversity is characterized for 270 single-copy polymorphic loci in cotton. A strategy for SNP discovery is defined to pre-screen loci for copy number and polymorphism. Our data indicate that the A and D genomes in both diploid and tetraploid cotton remain distinct from each such that paralogs can be distinguished. This research provides mapped DNA markers for intra-specific crosses and introgression of exotic germplasm in cotton.</p