Zero degrees: geographies of the prime meridian

Amino acid alignments of the species-specific OBPs clade in the E. balteatus and E. corollae. The motif of six conserved cysteines are marked with asterisks at the top. (JPEG 3067 kb

Additional file 2: Fig. S1. of Chemosensory genes in the antennal transcriptome of two syrphid species, Episyrphus balteatus and Eupeodes corollae (Diptera: Syrphidae)

(A) Species distribution and annotation summaries in the E. balteatus (Ebal) and E. corollae (Ecor) antennal transcriptome assembly. (B) Gene ontology classifications of the E. balteatus and E. corollae unigenes with Blast2GO program, including categories with biological process, molecular function and cellular component. (TIFF 3397 kb

Fumigant toxicity of <i>M</i>. <i>alternifolia</i> essential oil against <i>S</i>. <i>zeamais</i> adults.

<p>Fumigant toxicity of <i>M</i>. <i>alternifolia</i> essential oil against <i>S</i>. <i>zeamais</i> adults.</p

Overview of aerobic respiration and energy synthesis in the mitochondrial respiratory chain upon essential oil exposure.

<p>The complex I is a target-recognizing domain. The blue dotted arrowed line represents that essential oil affects the hydrogen carrier to block the electron flow. The genes encoding complex II-IV were down-regulated. The genes encoding tricarboxylic acid cycle (TCA), lipid, polysaccharide, and protein metabolism were up-regulated at different expression levels. CoASH, CoA, NADH, NAD⁺, CoQ, Cytc, ATP, ADP, Pi, H⁺, and e^- represent the hydrogensulfide coenzyme A, coenzyme A, nicotinamide adenine dinucleotide, nicotinamide, coenzyme Q, cytochrome C, adenosine triphosphate, adenosine diphosphate, phosphonates, hydrogenion, and electron, respectively.</p

Distribution of unigenes in different public databases.

<p>Distribution of unigenes in different public databases.</p

Top 11 enriched KEGG pathways between oil-fumigated and control samples.

<p>Top 11 enriched KEGG pathways between oil-fumigated and control samples.</p

Effect of <i>M</i>. <i>alternifolia</i> essential oil fumigation at different concentrations on acetylcholinesterase (AChE) (A), glutathione S-transferase (GST) (C), and carboxylesterase (CarE) (E), and at different times with sub-lethal concentration (LC₅₀) of oil (6.78 mg/L at 24 h) on AChE (B), GST (D), and CarE (F) in adult <i>S</i>. <i>zeamais in vivo</i>.

<p>CK represents the control groups. Results are reported as mean ± SE (calculated from three independent experiments). Different minor case letters at the top of the columns mean significant differences of essential oil at a <i>p</i> value of 0.05.</p

Summary statistics of the Illumina sequence reads of <i>S</i>. <i>zeamais</i> transcriptome and the corresponding assembly.

<p>Summary statistics of the Illumina sequence reads of <i>S</i>. <i>zeamais</i> transcriptome and the corresponding assembly.</p

GO (A) and KEGG (B) pathway analysis of DEGs of <i>S</i>. <i>zeamais</i> after oil- fumigation.

<p>GO (A) and KEGG (B) pathway analysis of DEGs of <i>S</i>. <i>zeamais</i> after oil- fumigation.</p

Functional Characterizations of Chemosensory Proteins of the Alfalfa Plant Bug <em>Adelphocoris lineolatus</em> Indicate Their Involvement in Host Recognition

<div><p>Insect chemosensory proteins (CSPs) have been proposed to capture and transport hydrophobic chemicals from air to olfactory receptors in the lymph of antennal chemosensilla. They may represent a new class of soluble carrier protein involved in insect chemoreception. However, their specific functional roles in insect chemoreception have not been fully elucidated. In this study, we report for the first time three novel CSP genes (<em>AlinCSP1-3</em>) of the alfalfa plant bug <em>Adelphocoris lineolatus</em> (Goeze) by screening the antennal cDNA library. The qRT-PCR examinations of the transcript levels revealed that all three genes (<em>AlinCSP1-3</em>) are mainly expressed in the antennae. Interestingly, these CSP genes <em>AlinCSP1-3</em> are also highly expressed in the 5^th instar nymphs, suggesting a proposed function of these CSP proteins (AlinCSP1-3) in the olfactory reception and in maintaining particular life activities into the adult stage. Using bacterial expression system, the three CSP proteins were expressed and purified. For the first time we characterized the types of sensilla in the antennae of the plant bug using scanning electron microscopy (SEM). Immunocytochemistry analysis indicated that the CSP proteins were expressed in the pheromone-sensitive sensilla trichodea and general odorant-sensitive sensilla basiconica, providing further evidence of their involvement in chemoreception. The antennal activity of 55 host-related semiochemicals and sex pheromone compounds in the host location and mate selection behavior of <em>A. lineolatus</em> was investigated using electroantennogram (EAG), and the binding affinities of these chemicals to the three CSPs (AlinCSP1-3) were measured using fluorescent binding assays. The results showed several host-related semiochemicals, (<em>Z</em>)-3-hexen-1-ol, (<em>E</em>)-2-hexen-1-al and valeraldehyde, have a high binding affinity with AlinCSP1-3 and can elicit significant high EAG responses of <em>A. lineolatus</em> antennae. Our studies indicate the three antennae-biased CSPs may mediate host recognition in the alfalfa plant bug <em>A. lineolatus</em>.</p> </div