## 3 Results
### The Effect of Different Hormones on the Color and Quality Traits of Grape Berry
#### 3.1.4 Effects of Different Hormones on Grape Volatile Compound
Among these five groups, the number of light-related elements was the largest, which might be due to the important role of light in photosynthesis for plant growth and development, followed by the hormone-related elements, whereas the number of cis-elements, responsive tissue-specific and circadian-related, were detected to be less. These motifs could indicate the corresponding miRNAs and potential functions of genes. The promoter vectors (pBI121-VvmiRR156b/c/d-35 SCsaMV) were conducted as shown in Figure 3A. After GUS histochemical staining, it was found that full-length promoter vectors of VvmiR156b/c/d (pBI121-VvmiRR156b/c/d-35 SCsaMV) were stained blue, and the positive control (pBI121 carrier with 35 SCsaMV promoter) also appeared blue, while the negative control (pBI121 carrier without 35 SCsaMV promoter) did not show a blue color, indicating that the promoter of VvmiR156b/c/d (pBI121-VvmiRR56b/c/d-35 SCsaMV) had GUS activity. After GA, ABA, MeJA, and NAA treatments, GUS staining of the VvmiR156b/c/d promoter vectors (pBI121-VvmiRR156b/c/d-35 SCsaMV) deepened and GUS activities were enhanced to a certain extent, while the positive control (pBI121 carrier with 35 SCsaMV promoter) remained almost unchanged (Figure 3B,C). Our results show that the VvmiR156b/c/d promoter regions contained multi-hormone cis-elements and responded to multi-hormone signals. The Expression Characteristics of VvmiRR156b/c/d and VvSPL9 Responsive to Various Hormones in the Modulation of Grape Color Formation  
3.3.1. Short-Term Response of VvmiR156b/c/d and _VvSPL9_ to Exogenous Hormones in 'Wink' Leaves  
To identify the transient induction effect of exogenous hormones on VvmiR156b/c/d and _VvSPL9_, the treated grape leaves with GA, ABA, MeJA, and NAA were used to detect the expression of VvmiR156b/c/d and _VvSPL9_. As Figure 4 shows, in the control samples, VvmiR156b/c/d exhibited lower expression levels at 1 HAT and 3 HAT, while showed higher expression levels at 5 HAT and 7 HAT; conversely, their targets showed the opposite expression modes, indicating the potential negative regulatory roles of VvmiR156b/c/d on _VvSPL9_. Furthermore, we revealed that among the four hormone treatments, GA significantly upregulated the expressions of VvmiR156b/c/d at 7 HAT and decreased _VvSPL9_ at the corresponding stage, thereby enhancing their negative correlation at the expression levels, which suggests that GA promoted the negative regulatory roles of VvmiR156b/c/d on _VvSPL9_. Although the other three hormone treatments nearly downregulated the expression levels of VvmiR156b/c/d and VvSPL9 at all times, the expression levels of VvmiR156b/c/d and VvSPL9 under the ABA, MeJA, and Auxin hormones treatments could still maintain a negative correlation, implying that these hormones mediate the  
Figure 3: GUS staining analysis of VvMIR156b/c/d promoters in response to exogenous hormones. (**A**) The promoter vector construction. (**B**) GUS staining. (**C**) GUS activity analysis. negative regulatory roles of VvmiR156b/c/d on VvSPL9. Meanwhile, the results suggest that these modules had a stronger response to GA than the remaining three hormones ABA, MeJA, and Auxin, similar to the GUS stain results above (Figure 3).