Fig. 3.

Expression profiles of PtrWRKY73 in P. trichocarpa. a Semi-quantitative PCR examined-PtrWRKY73 transcript levels in different tissues. Poplar 18S expression was used as a control. Total RNA was isolated from roots (R), stems (S), xylem (X), phloem (PH), petioles (P), old leaves (OL), young leaves (YL) and sprouts (SP). PtrWRKY73 promoter driving GUS expression in various tissues of A. thaliana including roots (b), stems (c), inflorescence (d), siliques (e), young leaves (f) and old leaves (g) of 4-week-old plants