## 2 Results
### Expression Profiles of McJAZ Genes in Response to JA and ABA Treatments  
Numerous reports have shown that MeJA and ABA play a vital role in regulating plant development, stress response, and various physiological processes through controlling the expression patterns of downstream genes [8; 18; 68; 69]. Hence, to next investigate the potential roles of _McJAZ_ genes in response to MeJA and ABA, qRT-PCR was performed to analyze the relative expression profiles of these _McJAZ_ genes in _M. canadensis_ that had been treated with MeJA or ABA. Based on qRT-PCR results, we found that the expres  
Figure 4: **Tissue-specific expression patterns of _M. canadensis McJAZ_ genes. (A) The different tissues used for total RNA extraction, including Root (R), Stem (S), Young Leaf (L) and Flower (F). The red arrow indicates the position at which root and leaf tissues were collected. (B) Quantitative real-time (qRT)-PCR analysis of each _McJAZ_ gene expression in the indicated _M. canadensis_ tissues. The expression level of each _McJAZ_ gene was normalized to _β-actin_ gene and relative expression values are compared in root. Data are presented as means \(\pm\) SE of three independent replicates, and significant differences between the expression level of each _McJAZ_ gene in root tissue versus other tissue was analyzed by Student’s _t_-test (* \(p\) < 0.05 or ** \(p\) < 0.01). sion pattern of each _McJAZ_ gene was variable under MeJA or ABA treatment (Figure 5). Under MeJA treatment, the transcript levels of seven _McJAZ_ genes were distinctly upregulated (Figure 5A), similar to previously reported transcriptome data (Supplemental Figure S1) [67]. In general, _McJAZ1_, _McJAZ2_, _McJAZ6_, and _McJAZ7_ transcript levels displayed a rapid increase, peaking at 1 h after MeJA exposure, and then gradually decreased at 3, 6, and 12 h, and returned to approximately control levels (CK 0 h) after prolonged MeJA exposure (24 h). In contrast, _McJAZ3_, _McJAZ4_, and _McJAZ5_ expression increased at 1 h after MeJA exposure, and significantly increased until a peak after 3 h, then gradually decreased after prolonged MeJA exposure (6, 12, and 24 h) (Figure 5A). In addition, we found that except for _McJAZ4_, the transcripts of _McJAZ_ genes were also dynamically affected by exogenous ABA treatment. Among them, _McJAZ2_, _McJAZ5_, and _McJAZ6_ transcript levels were significantly up-regulated at 1, 3, and 24 h for _McJAZ2_, at 1, 12, and 24 h for _McJAZ5_, and at 1 and 24 h for _McJAZ6_ after ABA exposure (Figure 5B). In particular, the expression levels of _McJAZ2_, _McJAZ5_, and _McJAZ6_ reached their highest levels at 14, 21, and 7 times higher than the control (CK 0 h) at 1 h respectively. Additionally, the expression of _McJAZ1_ was slightly up-regulated at 1 h, but down-regulated subsequently (3, 6, 12, and 24 h), and reached its lowest level at 6 h after ABA exposure. The transcript level of _McJAZ3_ was not obvious different at 1, 3, and 24 h, but was down-regulated at 6 and 12 h, compared with control (CK 0 h). _McJAZ7_ expression was slightly decreased after 1, 3, 6, and 12 h of ABA exposure, and then returned to a level comparable to that seen at the control time point (CK 0 h). These results revealed that _McJAZ_ genes  
Figure 5: **Expression profiles of _McJAZ_ genes under phytohormone MeJA and ABA treatments. Quantitative real-time (qRT)-PCR analysis of the expression levels of _McJAZ1_, _McJAZ2_, _McJAZ3_, _McJAZ4_, _McJAZ5_, _McJAZ6_, and _McJAZ7_ in the two-week-old _M.__candensis_ seedlings under 100 uM Methyl Jasmonate (MeJA) (**A**) or 20 uM abscisic Acid (ABA) (**B**) treatments for 0, 1, 3, 6, 12, and 24 h, respectively. The relative expression level of each _McJAZ_ gene was normalized to _βactin_ gene and compared with CK (0 h) as reference using the 2\({}^{-\Delta\Delta\text{CK}}\) method. Data are presented as means \(\pm\) SE of three independent replicates from three propagated cuttings.