Fig. 4

Weighted gene co-expression network analysis (WGCNA) of gut-expressed transcripts in Frankliniella occidentalis to identify modules of co-expressed transcripts associated with larval development and response to tomato spotted wilt virus infection. (A) Module-trait relationships depicting significant associations (correlations, P < 0.05) between clusters (modules) of co-expressed transcripts (left-hand column of colored blocks, i.e., module eigengenes) and time-larval stages (trait). Each trait includes normalized read counts of all gut-expressed transcripts from four biological replications and two conditions (both virus-exposed and non-exposed) of the gut RNA-seq analysis, i.e., eight samples per time-stage. Asterisks indicate eight modules that are significantly associated with time-larval stages. (B) Hierarchical clustering of module eigengenes. The dendrogram depicts relationships among modules (eigengenes) of co-expressed transcripts; positively correlated eigengenes cluster within the same clade. Asterisks indicate modules that include sets of differentially-expressed transcripts (DETs) in response to tomato spotted wilt virus infection. (C) Counts of larval gut DETs across 14 modules show enrichment in the 'turquoise', 'lightcyan' and 'blue' modules. 3-L1 = cohort of first instars three hours after removal of virus inoculum after a 24-h acquisition access period; 24-L2 = same cohort of insects developed into early second instars, 24 h after removal of inoculum; and 48-L2 = same cohort of insects entering into late second instars, 48 h after removal of inoculum