Cloning, molecular characterization and tissue exPression of an octoPamine/tyramine recePtor from sPotted wing drosoPhila (DROSOPHILA SUZUKII)

Spotted wing Drosophila (Drosophila suzukii) is a polyphagous pest arrived in Europe in 2009 able to infest a growing number of fruit and vine species, causing considerable economic damage. D. suzukii grows very rapidly (seven to fifteen generations per year) and shows a remarkable ability to adapt to climatic conditions and to new host plants. These characteristics make its populations particularly difficult to control. Octopamine (OA) and tyramine (TA) biogenic amines are present in traces in vertebrates, while in invertebrates they act as substitutes for adrenaline and noradrenaline. Indeed, these amines regulate numerous physiological processes in insects. They exert their effects by binding to specific receptor proteins that belong to the superfamily of G-protein coupled receptors (GPCRs). In this work, we have isolated complementary DNA (cDNA) coding for an amine receptor from Drosophila suzukii (DsTyr). The cloned cDNA is about 1.8kb long and encodes for a 601 amino acids protein. This polypeptide presents the classical seven transmembrane domains as revealed by hydropathic profile analysis. BLAST analysis of the sequence shows a high identity (>98%) to the octopamine/tyramine receptor from Drosophila melanogaster. DsTyr1 deduced sequence will be compared to the amino acid sequence of octopamine/tyramine receptors from other insects. Furthermore, the various receptor sequences will be characterized by phylogenetic analysis. The expression level of the receptor will be studied by qRT-PCR analysis in different parts of D. suzukii male and female body (head, thorax and abdomen). With this work, we present a first structural and functional description of an octopamine/tyramine receptor from Drosophila suzukii

Mating behaviour and dual mode communication of Pear Psylla CACOPSYLLA PYRI

Cacopsylla pyri (L.) (Hemiptera, Psyllidae) is one of the most important pests of European pear, and its management generally depends on the use of chemical insecticides, but C. pyri outbreaks are sometime observed. Ecological control strategies should be desirable and the knowledge of mating behavior is crucial to develop new ones. A multi-approaches research aimed to acquire knowledges about C. pyri mate finding. Electroantennographic (EAG) analyses and olfactometric bioassays were used to evaluate the activity of intraspecific semiochemicals on C. pyri. The EAG amplitudes revealed that volatile compounds, present in female cuticular extracts, elicited dose-dependent responses in males, indicating that these compounds were able to stimulate the male olfactory system. In behavioral bioassays, living females and female cuticular extracts, attracted summerform males in a highly significant manner. Gas chromatography-mass spectrometry revealed that 13-methylheptacosane, 11,13-dimethylheptacosane, 2-methylheptacosane and 3-methylheptacosane were found in larger amounts in female extracts than in male ones, which suggests their role in male attraction. In addition, a laser vibrometer device was used to detect a male-female substrate-born vibrations pattern during pre-copulatory period. The female vibrational signal was recorded as mp3 and conveyed, in loop using a minishaker, on pear shoots with C. pyri virgin pairs to interfere with the mating by masking the natural communications

Mining genes involved in indoxacarb resistance of Lobesia botrana (Denis and Schifferm\ufcller) by de novo transcriptome assembly and differential expression analysis.

Lobesia botrana (Denis and Schifferm\ufcller) (Lepidoptera: Tortricidae) is one of the most important grapevine pests in Europe but, being a non-model organism, only limited genomic and transcriptomic resources are available for functional studies at the molecular level, such as those relevant to insecticide resistance and pest control. Hence, to gain insight into the mechanism of indoxacarb resistance, a blocker of insect voltage-gated sodium channels (NaV), we analysed the transcriptome and expression profile in 2nd instars of L. botrana from susceptible and field selected populations (LC50 resistance ratio 72). De novo transcriptome assembly using Trinity resulted in 141,581 isoforms clustered in 94,290 putative genes. The transcriptome completeness was supported by BUSCO: 92% of conserved orthologs (n= 1,658) were retrieved as a complete sequence, 6.3% displayed fragmented ORFs, and only 1.7% were missing. 36,250 genes were preliminary annotated relaying on the longest isoform per gene, by running Annocript pipeline against non-redundant protein databases (Nr), gene ontology (GO), cluster of orthologous groups of proteins (COG), KEGG orthology (KO) and long non-coding RNAs (lncRNAs). Conditional Reciprocal Best BLAST analysis of protein isoforms performed on Lepidoptera proteomes identified putative orthologs of multigene family members potentially involved in metabolic resistance (61 cytochrome P450 monooxygenases, 25 glutathione S-transferases, 13 carboxylesterases, 25 UDP-glucuronosyltransferases) as well as alternatively spliced isoforms of the NaV gene. Among 263 upregulated and annotated genes in the resistant population, functional GO enrichment analysis revealed overrepresentation of terms for cytochrome P450, due to up-regulation of CYP6B and CYP9A subfamily members as well as increased transcript level for UGT genes. Hydrolases were, on the contrary, overrepresented in 293 annotated genes, downregulated in the resistant population. These data tentatively suggest the reduced susceptibility to indoxacarb might be related to an increase of Phase I and II detoxification along with reduced bioactivation of the insecticide

X-linked heterochromatin distribution in the holocentric chromosomes of the green apple aphid Aphis pomi

Chromatin organization in the holocentric chromosomes of the green apple aphid Aphis pomi has been investigated at a cytological level after C-banding, NOR, Giemsa, fluorochrome staining and fluorescent in situ hybridization (FISH). C-banding technique showed that heterochromatic bands are exclusively located on X chromosomes. This data represents a peculiar feature that clearly contradicts the equilocal distribution of heterochromatin typical of monocentric chromosomes. Moreover, silver staining and FISH carried out with a 28S rDNA probe localized rDNA genes on one telomere of each X chromosome; CMA(3) staining reveals that these silver positive telomeres are, the only GC-rich regions among A. pomi heterochromatin, whereas all other C-positive bands are DAPI positive thus containing AT-rich DNA

Distribution of heterochromatin and rDNA on the holocentric chromosomes of the aphids Dysaphis plantaginea and Melanaphis pyraria (Hemiptera: Aphididae)

The structure of the holocentric chromosomes of the rosy apple aphid, Dysaphis plantaginea (2n = 12), and pear-grassaphid, Melanaphis pyraria (2n = 8), was studied using C-banding, NOR, Giemsa and fluorochrome staining, and fluorescent in situhybridization (FISH). Contrary to the equilocal distribution of heterochromatin typical of monocentric chromosomes, in both species C-banding evidenced a tendency of highly repetitive DNAs to be restricted to the X chromosomes. Silver staining and FISH, using a 28S rDNA probe, located rDNA genes on one telomere of each X chromosome, the only brightly fluorescent C-positive sites revealed by CMA3 staining, whereas all other heterochromatic C-bands were DAPI positive. Both species showed a noticeable amount of rDNA heteromorphism. Mitotic recombination is proposed as a possible mechanism responsible for the variation in size of rDNA

Candidate Acetic Acid Bacteria Strains for Levan Production

In this study, twelve strains of acetic acid bacteria (AAB) belonging to five different genera were tested for their ability to produce levan, at 70 and 250 g/L of sucrose concentration, respectively. The fructan produced by the bacterial strains was characterized as levan by NMR spectroscopy. Most of the strains produced levan, highlighting intra- and inter-species variability. High yield was observed for Neoasaia chiangmaiensis NBRC 101099 T, Kozakia baliensis DSM 14400 T and Gluconobacter cerinus DSM 9533 T at 70 g/L of sucrose. A 12-fold increase was observed for N. chiangmaiensis NBRC 101099 T at 250 g/L of sucrose concentration. Levan production was found to be affected by glucose accumulation and pH reduction, especially in Ko. baliensis DSM 14400 T. All the Gluconobacter strains showed a negative correlation with the increase in sucrose concentration. Among strains of Komagataeibacter genus, no clear effect of sucrose on levan yield was found. Results obtained in this study highlighted the differences in levan yield among AAB strains and showed interdependence between culture conditions, carbon source utilization, and time of incubation. On the contrary, the levan yield was not always related to the sucrose concentration

Interplay of Chimeric Mating-Type Loci Impairs Fertility Rescue and Accounts for Intra-Strain Variability in Zygosaccharomyces rouxii Interspecies Hybrid ATCC42981

The pre-whole genome duplication (WGD) Zygosaccharomyces clade comprises several allodiploid strain/species with industrially interesting traits. The salt-tolerant yeast ATCC42981 is a sterile and allodiploid strain which contains two subgenomes, one of them resembling the haploid parental species Z. rouxii. Recently, different mating-type-like (MTL) loci repertoires were reported for ATCC42981 and the Japanese strain JCM22060, which are considered two stocks of the same strain. MTL reconstruction by direct sequencing approach is challenging due to gene redundancy, structure complexities, and allodiploid nature of ATCC42981. Here, DBG2OLC and MaSuRCA hybrid de novo assemblies of ONT and Illumina reads were combined with in vitro long PCR to definitively solve these incongruences. ATCC42981 exhibits several chimeric MTL loci resulting from reciprocal translocation between parental haplotypes and retains two MATa/MAT\u3b1 expression loci, in contrast to MAT\u3b1 in JCM22060. Consistently to these reconstructions, JCM22060, but not ATCC42981, undergoes mating and meiosis. To ascertain whether the damage of one allele at the MAT locus regains the complete sexual cycle in ATCC42981, we removed the MAT\u3b1 expressed locus by gene deletion. The resulting MATa/- hemizygous mutants did not show any evidence of sporulation, as well as of self- and out-crossing fertility, probably because incomplete silencing at the chimeric HML\u3b1 cassette masks the loss of heterozygosity at the MAT locus. We also found that MAT\u3b1 deletion switched off a2 transcription, an activator of a-specific genes in pre-WGD species. These findings suggest that regulatory scheme of cell identity needs to be further investigated in Z. rouxii protoploid yeast

Draft Genome Sequences of the Highly Halotolerant Strain Zygosaccharomyces rouxii ATCC 42981 and the Novel Allodiploid Strain Zygosaccharomyces sapae ATB301T Obtained Using the MinION Platform

Here, we report draft genome sequences of the halotolerant and allodiploid strains Zygosaccharomyces rouxii ATCC 42981 and Zygosaccharomyces sapae ABT301T. Illumina and Oxford Nanopore MinION sequencing revealed genome sizes of 20.9 and 24.7\u2009Mb, respectively. This information will be useful for deciphering the genetics of hybrid adaptation to high salt and sugar concentrations in nonconventional yeasts