Identification of drought-related co-expression modules and hub genes in potato roots based on WGCNA

Weighted gene co-expression network analysis (WGCNA) is a research method in systematic biology. It is widely used to identify gene modules related to target traits in multi-sample transcriptome data. In order to further explore the molecular mechanism of potato response to drought stress, two cultivars (C16: CIP 397077.16 and C119: CIP 398098.119) introduced from the International Potato Center were used as experimental materials, and five drought stress gradients were treated for 0 h, 2 h, 6 h, 12 h, and 24 h, with the untreated material as a control. A total of 30 samples of root system were used for transcriptome sequencing, with three biological replicates. Based on the above transcriptome data, we constructed a co-expression network of weighted genes associated with stress-resistant physiological traits by WGCNA, and obtained 15 gene co-expression modules closely related to root drought resistance. In addition, a number of hub genes involved in drought stress regulation pathways were discovered from the four modules with the highest correlation with target traits. These results provide clues for further study on the molecular genetic mechanisms of potato root drought resistance.