Data from: Gene expression and drought response in an invasive thistle

Identification of the molecular changes associated with successful invasions can offer clues regarding the mechanistic basis of such hypotheses, even in non-model organisms. To complement studies of phenotypic variation, we investigate gene expression during drought response that might underlie variation in drought tolerance between native and introduced populations of diffuse knapweed (Centaurea diffusa), and possibly contribute to invasion success.

Using species-specific microarrays and tissue sampled under drought and control conditions at three time points, we identified genes whose expression either varied constitutively or responded to drought stress differently between ranges. Further, we functionally investigate these genes. Based on these data, invasive populations have constitutively higher levels of expression relating to energy production and lower levels of signal transduction expression relative to native populations.

Under drought conditions, invasive populations may maintain energy production and react less strongly to drought than native populations, which may allow them to maintain fitness across moderate environmental variation. This supports the expectation of invasive populations consisting of generalist genotypes capable of fitness homeostasis, which may have facilitated the successful invasion of many environments in North America.

Usage notes

Supplementary tables and figures Cdiff_expression_supmat_BiolInv.docx TableS3_LRTs LRTsandTAIRaccessions.xlsx TableS5GOresults_Drought GOresults_sigTrt_pc.xlsx PreprocessedMicroarrayData knn_xys.zip Full_LRTs_Results Cdifexprs_lme4dat.txt ProcessedExpressionDataMatrix Cdif_exprs_matrix.txt Code repository Github repository storing R scripts used in this paper. Raw gene expression data RawData_Cdifexprs.zip.gz