Discovery of thiadiazoles as a novel structural class of potent and selective PDE7 inhibitors. Part 2: metabolism-directed optimization studies towards orally bioavailable derivatives

The synthesis and optimization of pharmacokinetic parameters of structurally novel small PDE7 inhibitors is discussed.     

Genetic map of artichoke × wild cardoon: toward a consensus map for <Emphasis Type="Italic">Cynara cardunculus</Emphasis>

An integrated consensus linkage map is proposed for globe artichoke. Maternal and paternal genetic maps were constructed on the basis of an F₁ progeny derived from crossing an artichoke genotype (Mola) with its progenitor, the wild cardoon (Tolfa), using EST-derived SSRs, genomic SSRs, AFLPs, ten genes, and two morphological traits. For most genes, mainly belonging to the chlorogenic acid pathway, new markers were developed. Five of these were SNP markers analyzed through high-resolution melt technology. From the maternal (Mola) and paternal (Tolfa) maps, an integrated map was obtained, containing 337 molecular and one morphological markers ordered in 17 linkage groups (LGs), linked between Mola and Tolfa. The integrated map covers 1,488.8 cM, with an average distance of 4.4 cM between markers. The map was aligned with already existing maps for artichoke, and 12 LGs were linked via 31 bridge markers. LG numbering has been proposed. A total of 124 EST-SSRs and two genes were mapped here for the first time, providing a framework for the construction of a functional map in artichoke. The establishment of a consensus map represents a necessary condition to plan a complete sequencing of the globe artichoke genome.     

Evolutionarily conserved paired immunoglobulin-like receptor α (PILRα) domain mediates its interaction with diverse sialylated ligands

Paired immunoglobulin-like receptor (PILR) α is an inhibitory receptor that recognizes several ligands, including mouse CD99, PILR-associating neural protein, and Herpes simplex virus-1 glycoprotein B. The physiological function(s) of interactions between PILRα and its cellular ligands are not well understood, as are the molecular determinants of PILRα/ligand interactions. To address these uncertainties, we sought to identify additional PILRα ligands and further define the molecular basis for PILRα/ligand interactions. Here, we identify two novel PILRα binding partners, neuronal differentiation and proliferation factor-1 (NPDC1), and collectin-12 (COLEC12). We find that sialylated O-glycans on these novel PILRα ligands, and on known PILRα ligands, are compulsory for PILRα binding. Sialylation-dependent ligand recognition is also a property of SIGLEC1, a member of the sialic acid-binding Ig-like lectins. SIGLEC1 Ig domain shares ～22% sequence identity with PILRα, an identity that includes a conserved arginine localized to position 97 in mouse and human SIGLEC1, position 133 in mouse PILRα and position 126 in human PILRα. We observe that PILRα/ligand interactions require conserved PILRα Arg-133 (mouse) and Arg-126 (human), in correspondence with a previously reported requirement for SIGLEC1 Arg-197 in SIGLEC1/ligand interactions. Homology modeling identifies striking similarities between PILRα and SIGLEC1 ligand binding pockets as well as at least one set of distinctive interactions in the galactoxyl-binding site. Binding studies suggest that PILRα recognizes a complex ligand domain involving both sialic acid and protein motif(s). Thus, PILRα is evolved to engage multiple ligands with common molecular determinants to modulate myeloid cell functions in anatomical settings where PILRα ligands are expressed.     

The classical nuclear localization signal receptor, importin-alpha, is required for efficient transition through the G1/S stage of the cell cycle in Saccharomyces cerevisiae

There is significant evidence linking nucleocytoplasmic transport to cell cycle control. The budding yeast, Saccharomyces cerevisiae, serves as an ideal model system for studying transport events critical to cell cycle progression because the nuclear envelope remains intact throughout the cell cycle. Previous studies linked the classical nuclear localization signal (cNLS) receptor, importin-alpha/Srp1, to the G(2)/M transition of the cell cycle. Here, we utilize two engineered mutants of importin-alpha/Srp1 with specific molecular defects to explore how protein import affects cell cycle progression. One mutant, Srp1-E402Q, is defective in binding to cNLS cargoes that contain two clusters of basic residues termed a bipartite cNLS. The other mutant, Srp1-55, has defects in release of cNLS cargoes into the nucleus. Consistent with distinct in vivo functional consequences for each of the Srp1 mutants analyzed, we find that overexpression of different nuclear transport factors can suppress the temperature-sensitive growth defects of each mutant. Studies aimed at understanding how each of these mutants affects cell cycle progression reveal a profound defect at the G(1) to S phase transition in both srp1-E402Q and srp1-55 mutants as well as a modest G(1)/S defect in the temperature-sensitive srp1-31 mutant, which was previously implicated in G(2)/M. We take advantage of the characterized defects in the srp1-E402Q and srp1-55 mutants to predict candidate cargo proteins likely to be affected in these mutants and provide evidence that three of these cargoes, Cdc45, Yox1, and Mcm10, are not efficiently localized to the nucleus in importin-alpha mutants. These results reveal that the classical nuclear protein import pathway makes important contributions to the G(1)/S cell cycle transition.     

Desmosomal adhesion: structural basis,molecular mechanism and regulation (Review)

Desmosomes are adhesive intercellular junctions of epithelia and cardiac muscle. They have an essential function in maintaining the integrity of tissues, which is compromised in human genetic and autoimmune disease that targets desmosomal components. Recent evidence (1) suggests new roles for the function of desmosomal adhesion in tissue morphogenesis, (2) gives new insights into the molecular mechanism of adhesion, (3) indicates that the desmosomal adhesion molecules, desmocollin and desmoglein, may contribute to the regulation of epidermal diffentiation, and (4) shows that the affinity of desmosomal adhesion is regulated by protein kinase C.     

Klinische,pathologisch-anatomische,thermographische und radiologische Befunde bei einer Giraffe mit chronischer Arthritis

Chronic arthritis is a known medical problem in many species also in artiodactyla. The moist coldness that exists in the latitudes of Germany enhances this condition in animals that are accustomed to dry coldness in their natural habitats. This case report shows that thermography can be used for the assessment of arthritis in giraffes. Post-mortem results of pathology and computed tomography confirm the diagnosis based on thermography. Thermal imaging is a practical, non-invasive diagnostic tool for examining animals without stress and anesthesia.     

A rapid (one day), sensitive real-time polymerase chain reaction assay for detecting Escherichia coli O157:H7 in ground beef

The purpose of this study was to apply our rapid, integrated double enrichment 5' nuclease real-time polymerase chain reaction assay for the detection of Escherichia coli O157:H7 and evaluate its efficacy. The assay targeted ground beef, an important vehicle in disease epidemiology. The assay reliably determined in 8 h the presence of E. coli O157:H7 in ground beef at the level of 1 colony-forming unit (CFU)/g. The sensitivity and specificity of the assay were compared with that of standard enrichment diagnostic techniques. A correlation of 100% in detection was achieved to the limit of 1 CFU/g. This assay can be used as a rapid, automatic process for identification of E. coli O157:H7 in ground beef or can be integrated with standard culture procedures, resulting in considerable cost and time savings.     

Plant Chitinases: Genetic Diversity and Physiological Roles

Chitinase proteins are widely distributed across diverse biological systems. Chitinases hydrolyze chitin, chitosan, lipochitooligosaccharides, peptidoglycan, arabinogalactan and glycoproteins containing N-acetylglucosamine. Analyses of genome-wide sequence and microarray expression profilings show that chitinase genes are represented by large families and the individual member genes are expressed in diverse conditions. Chitinase proteins are members in the group of the pathogenesis-related proteins that are strongly induced when host plant cells are challenged by pathogen stress and thus chitinases constitute an important arsenal of plants against fungal pathogens. Transgenic plants have been produced that overexpress chitinases alone or in conjunction with other defense-related proteins. The phenotype analyses of such plants have shown enhanced disease resistance in large number of cases. Apart from defense against pathogen stress, chitinases are implicated in relationships between plant cells and fungi (e.g., mycorrhizae associations) and bacteria (e.g., legume/Rhizobium associations). Chitinases are also involved in plant abiotic stress responses as noted for osmotic, salt, cold, wounding and heavy metal stresses. Chitinases play a role in developmental aspects of plants too (i.e., regulation of plant embryogenesis process). A detailed account of the genetic diversity and functional aspects of plant chitinases is presented in this review.