Fig. 6
The relative expression patterns of PtrINV genes in different tissue types of P. trifoliata during low temperature. RNA was extracted from 4 °C treated leaves (CL, A), stems (CS, B) and roots (CR, C) of two-month old P. trifoliata seedlings for (0 h, 6 h, 12 h, 24 h, 48 h, 72 h) and recovered (Rec) at room temperature for a day. Real-time quantitative PCR (qRT-PCR) assay was performed using specific primers and PtrActin gene was utilized as a reference gene. The gene expression analysis for each time point was repeated for at least two times with four biological replicates and representative data are shown. The relative gene expression was calculated using the 2-∆∆CT method relatively to the initial treatment time (0 h) that set as 1. The normalized values of the expression levels were converted into Log2 of expression values and visualized by heatmap figure. Heatmap figures were constructed by TBtools based on default features: Euclidean distance method and complete cluster method. (n = 3)