On the reported occurrence of a fusicoccin conjugate in maize cobs

The occurrence in immature maize cobs of a fusicoccin derivative, reported in 1980 by Russian workers, could not be confirmed. Extraction and fractionation procedures were identical to those used by the Soviet authors and the analysis of the fractions mainly relied on a very sensitive and specific radioimmunoassay. Possible reasons for these contradictory results are discussed.     

Presence of esterase inPinaceae pollen

General esterases, like wall heterologous enzymes, may be implicated in allergenic mechanisms. We cytochemically examined the presence of these enzymes, bearing in mind thatPinus spp. is often considered a possible cause of allergies. Positive esterase results in fungus spores were found on the strip of a volumetric sampler. Data are reported here, together with the hypothesis of a possible esterase-allergenic link regarding fungus spores.     

Sexual Reproduction in Aspergillus flavus Sclerotia: Acquisition of Novel Alleles from Soil Populations and Uniparental Mitochondrial Inheritance

Aspergillus flavus colonizes agricultural commodities worldwide and contaminates them with carcinogenic aflatoxins. The high genetic diversity of A. flavus populations is largely due to sexual reproduction characterized by the formation of ascospore-bearing ascocarps embedded within sclerotia. A. flavus is heterothallic and laboratory crosses between strains of the opposite mating type produce progeny showing genetic recombination. Sclerotia formed in crops are dispersed onto the soil surface at harvest and are predominantly produced by single strains of one mating type. Less commonly, sclerotia may be fertilized during co-infection of crops with sexually compatible strains. In this study, laboratory and field experiments were performed to examine sexual reproduction in single-strain and fertilized sclerotia following exposure of sclerotia to natural fungal populations in soil. Female and male roles and mitochondrial inheritance in A. flavus were also examined through reciprocal crosses between sclerotia and conidia. Single-strain sclerotia produced ascospores on soil and progeny showed biparental inheritance that included novel alleles originating from fertilization by native soil strains. Sclerotia fertilized in the laboratory and applied to soil before ascocarp formation also produced ascospores with evidence of recombination in progeny, but only known parental alleles were detected. In reciprocal crosses, sclerotia and conidia from both strains functioned as female and male, respectively, indicating A. flavus is hermaphroditic, although the degree of fertility depended upon the parental sources of sclerotia and conidia. All progeny showed maternal inheritance of mitochondria from the sclerotia. Compared to A. flavus populations in crops, soil populations would provide a higher likelihood of exposure of sclerotia to sexually compatible strains and a more diverse source of genetic material for outcrossing.     

The Cochlostoma (Holcopoma) westerlundi group in Italy (Caenogastropoda: Cochlostomatidae)

Currently, the Cochlostoma (Holcopoma) westerlundi (Paulucci, 1879) group includes three subspecies inhabiting southern Italy up to southeastern Sicily. C. w. westerlundi (Paulucci, 1879) is limited to southern Calabria, C. w. yapigium (Westerlund, 1885) is widespread across the Salento (the southeastern extremity of the Apulia region) and C. w. dionysii (Paulucci, 1879) is endemic to the environs of Siracusa (SE Sicily). There is also a fourth taxon, C. paganum (Westerlund, 1885) described for Otranto (LE, Apulia), considered a synonym of C. w. yapigium. Up to now, the molecular genetics of C. westerlundi s.l. have been unknown and the morphological data of several populations are still lacking. Hence, the systematic classification of the group is tentative. Aiming at filling this gap, mtDNA (16S rDNA and COI) partial sequences were investigated and, in addition, the reproductive apparatus of C. w. westerlundi was described for the first time. Molecular sequences and anatomical data were used to test the taxonomic and phylogenetic status of the examined populations. Maximum Likelihood and Bayesian analysis revealed three clusters, strongly supported, corresponding to the three taxa. For the first time, synonymy between paganum and yapigium was confirmed by molecular evidence. Genetic distances between groups (D_xyJC) ranged from 2.6% to 5% (16S rDNA) and from 6.3% to 8.3% (COI). Molecular and morphological data led us to suggest elevating the three subspecies to the species rank.     

Triterpene glycosides with in vitro anti-inflammatory activity from Cyclamen repandum tubers

A new triterpene glycoside, repandoside (1) was isolated together with six known saponins (2-7) from the methanol extract of Cyclamen repandum tubers. The isolated saponins were characterized by high resolution mass spectrometry and both 1D and 2D NMR experiments. The in vitro effect of saponins on LPS-induced IL-8 and TNF-α mRNA level (by quantitative RT-PCR) and protein release (by ELISA) was evaluated in human THP-1 macrophages. We found that compounds 1 (repandoside), 2 (deglucocyclamin) and 4 (anagalloside B) at 100 μM inhibited the LPS-induced IL-8 and TNF-α expressions.     

Functional annotation of genes overlapping copy number variants in autistic patients: focus on axon pathfinding

We have used Gene Ontology (GO) and pathway analyses to uncover the common functions associated to the genes overlapping Copy Number Variants (CNVs) in autistic patients. Our source of data were four published studies [1-4]. We first applied a two-step enrichment strategy for autism-specific genes. We fished out from the four mentioned studies a list of 2928 genes overall overlapping 328 CNVs in patients and we first selected a sub-group of 2044 genes after excluding those ones that are also involved in CNVs reported in the Database of Genomic Variants (enrichment step 1). We then selected from the step 1-enriched list a sub-group of 514 genes each of which was found to be deleted or duplicated in at least two patients (enrichment step 2). The number of statistically significant processes and pathways identified by the Database for Annotation, Visualization and Integrated Discovery and Ingenuity Pathways Analysis softwares with the step 2-enriched list was significantly higher compared to the step 1-enriched list. In addition, statistically significant GO terms, biofunctions and pathways related to nervous system development and function were exclusively identified by the step 2-enriched list of genes. Interestingly, 21 genes were associated to axon growth and pathfinding. The latter genes and other ones associated to nervous system in this study represent a new set of autism candidate genes deserving further investigation. In summary, our results suggest that the autism's "connectivity genes" in some patients affect very early phases of neurodevelopment, i.e., earlier than synaptogenesis.     

Outer membrane vesicles from group B Neisseria meningitidis delta gna33 mutant: proteomic and immunological comparison with detergent-derived outer membrane vesicles

We compared the proteome of detergent-derived group B Neisseria meningitidis (MenB) outer membrane vesicles (DOMVs) with the proteome of outer membrane vesicles (m-OMVs) spontaneously released into culture supernatant by MenB delta gna33, a mutant in which the gene coding for a lytic transglycosylase homologous to the E. coli MltA was deleted. In total, 138 proteins were identified in DOMVs by 1- and 2-DE coupled with MS; 64% of these proteins belonged to the inner membrane and cytoplasmic compartments. By contrast, most of the 60 proteins of m-OMVs were classified by PSORT as outer membrane proteins. When tested for their capacity to elicit bactericidal antibodies, m-OMVs elicited a broad protective activity against a large panel of MenB strains. Therefore, the identification of mutations capable of conferring an OMV-releasing phenotype in bacteria may represent an attractive approach to study bacterial membrane composition and organization, and to design new efficacious vaccine formulations.     

TFG binds LC3C to regulate ULK1 localization and autophagosome formation

The early secretory pathway and autophagy are two essential and evolutionarily conserved endomembrane processes that are finely interlinked. Although growing evidence suggests that intracellular trafficking is important for autophagosome biogenesis, the molecular regulatory network involved is still not fully defined. In this study, we demonstrate a crucial effect of the COPII vesicle‐related protein TFG (Trk‐fused gene) on ULK1 puncta number and localization during autophagy induction. This, in turn, affects formation of the isolation membrane, as well as the correct dynamics of association between LC3B and early ATG proteins, leading to the proper formation of both omegasomes and autophagosomes. Consistently, fibroblasts derived from a hereditary spastic paraparesis (HSP) patient carrying mutated TFG (R106C) show defects in both autophagy and ULK1 puncta accumulation. In addition, we demonstrate that TFG activity in autophagy depends on its interaction with the ATG8 protein LC3C through a canonical LIR motif, thereby favouring LC3C‐ULK1 binding. Altogether, our results uncover a link between TFG and autophagy and identify TFG as a molecular scaffold linking the early secretion pathway to autophagy.