A salivary chitinase of Varroa destructor influences host immunity and mite's survival

This dataset represents raw data underlying the findings (and the figures) reported in the manuscript "A salivary chitinase of Varroa destructor influences host immunity and mite’s survival".

Fig 2A. Salivary gland expression of putative host regulation factors present found in the predicted secretome of Varroa destructor. (A) Relative expression data of 3 selected candidates are presented as mean fold changes of 3-4 independent biological replicates. Each replicate consisted of a pool of 5-10 mites and comprised , from which the RNA was extracted from,two samples: salivary glands (SG), and from the rest of the whole body, deprived of salivary glands (Whole Body – SG). Values on Y-axis are reported in Log₁₀ scale. Error bars represent standard error of the meandeviation (SD). Statistically significant differences are denoted with an asterisk (P < 0.005).

Fig 4. Survival of Varroa. destructor as affected by RNAi-mediated silencing of the gene encoding VdCHIsal. (A) Relative expression of Vd-CHIsal after mite soaking in a dsRNA solution. qRT-PCR data are presented as mean fold changes of 2-67 independent biological replicates. Each replicate consisted in a pool of 2-3 mites. Each time point was separately analyzed and the 0.9% NaCl 0.9% control sample was used as calibrator. Mean dCt values within each time point were compared by Student’s t-testone-way ANOVA followed by Tukey’s post-hoc test. Mean values denoted with different letters are significantly different. Error bars represent standard deviation (the standard error of the meanSD). Mean values denoted with asterisks are significantly different (*p<0.05; ** p<0.01). (B) Kaplan-Meier survival curves of mites soaked in a solution of dsRNA targeting Vd-CHIsal. Saline controls (0.9% NaCl), GFP dsRNA and Vd-CHIsal dsRNA soaked mites (blue rhombus, green circles and orange squares, respectively) were individually maintained on the same host pupa throughout the whole duration of the assayP. Subjects at risk were 18, 30 and 45 for 0.9% NaCl, GFP dsRNA and Vd-CHIsal dsRNA treatments, respectively. Survival curve of dsVd-CHIsal was significantly different from dsGFP (log rank test: X₂= 6.086; P=0.0136) and from NaCl 0.9 (log rank test: X₂=6.611; P=0.0101), while no difference was observed between dsGFP and NaCl 0.9% (log rank test: X₂= 0.46; P=0.49). Statistical significance was set at 0.016 (Bonferroni correction). aIn a separateconcurrent set of trials, host pupae were replaced every 24 h for both saline controls (0.9% NaCl) and Vd-CHIsal dsRNA soaked mites (violet  down-pointing and red up-pointing triangles, respectively). Subjects at risk were 29 and 22 for 0.9% NaCl and Vd-CHIsal dsRNA, respectively. Host pupae were maintained throughout the feeding or replaced every 24 h. Survival curve of dsVd-CHIsal was significantly different from  (log rank test: X₂= 18.21; P<0.0001), Statistical significance was set at 0.05.Statistical details are in the text. Error bars represent the standard error of the mean.

Fig 5.  Differentially expressed genes in honey bee pupae artificially infested with mites delivering saliva with the full repertoire of proteins or lacking Vd-CHIsal. (A) Differential expression of 13 honey bee genes, as affected by presence of Vd-CHIsal in the saliva (KD/WS). DESeq2 adjusted P was < 0.05 and FDR was set at 5%. Log transformed mean FPKM values are reported on Y axis. For each Each group representsexperimental condition  3 individually analyzedseparate  pupae were analyzed. Error bars represent SEMSD. Summary tables data sheets of differential expression analysis are presented in S2 and S3 Tables. (B) Relative expression of immune-related genes in honey bee pupae as affected by Vd-CHIsal expression in Varroa destructor infesting mites. Each groupmean value  representsis obtained on 7-10 individually analyzed pupae, individually analyzed. Results of qRT-PCR are presented as mean fold changes relative to non-infested pupae used as calibrator. Values on Y axis are reported in Log₁₀ scale. Error bars represent standard deviation (the standard error of the meanSD). Mean values were compared by one-way ANOVA, followed by Tukey post-hoc test, and values statistically different are denoted with different letters (P<0.05). Detailed resultsDetails of statistical analyses are presented in S4 Table. NP: non-parasitized controls; WS: pupae infested with mites soaked in saline solution; KD: pupae infested with mites soaked in a solution of dsRNA Vd-CHIsal dsRNA dsRNA solution.

S1 File. Table resulting from Trinotate in-house annotation of the putatively secreted components of Varroa destructor predicted proteome. The annotation was performed following the protocol described in Materials and Methods section. Content of columns is hereafter described. A: GenBank accession number of the original transcript of V. destructor; B:  GenBank accession number of the matching  protein in V. destructor; C: ID name assigned by Transdecoder software; D: coordinates of the translation; E: top BLASTp hits in Swiss-Prot db;  F: top BLASTp hits in the database of Hymenoptera venom; G: top BLASTp hits in the database of Acarina saliva; H: Pfam hits; I,: SignalP results indicating the presence of the signal peptide; J: TMHMM results indicating the presence of transmembrane domains; K: eggnog db hits; L: Kegg db hits; M: gene ontology retrieved from BLASTp; N: gene ontology retrieved from Pfam.