## 3 Results and Discussion
### In Silico Evaluation Results
#### 3.2.2 Docking Between IAA7 and the Ligands IAA and FCF  
The binding energy for the interaction between the auxin receptor IAA7 and its endogenous ligand IAA (IAA7-IAA) was \(-5.0\) kcal/mol, involving interactions with amino acids ARG12, LYS13, VAL8, and ASN10. Conversely, docking analysis between IAA7 and FCF revealed a binding energy of \(-5.4\) kcal/mol involving residues ARG12, LYS13, PRO6, ASN10, and TYR11. This indicates that IAA7 exhibits a slightly higher affinity for FCF than its endogenous ligand, underscoring the potential of FCF as an alternative ligand.  
Figure 7 illustrates the 3D interaction models of the IAA7 receptor with (a) its endogenous ligand IAA and (b) FCF, as well as the corresponding 2D interaction maps (c,d).  
These results suggest that FCF has a marginally higher affinity than the endogenous ligand and could potentially modulate the action mechanisms of the IAA7 receptor. Therefore, it is proposed that FCF may be recognized by the auxin (IAA7) and gibberellin (GA3 Ox2) receptors, potentially eliciting a response in plants supporting root elongation and vegetative growth.  
Table 3 summarizes the affinity energy and the amino acids involved in the interactions between each receptor and its ligands. Notably, amino acids HIS27 and ILE119 demonstrate recurrent interactions with the GA3 Ox2 receptor, while ARG12, LYS13, and ASN10 typically interact with the IAA7 receptor, highlighted in bold.  
Figure 6: Docking results with the GA3 Ox2 receptor. Interaction spheres with (**a**) GA3 and (**b**) FCF, and 2D interaction maps with (**c**) GA3 and (**d**) FCF.  
As [PERSON] et al. [42] noted, the gibberellin receptor (GA3 Ox2) stimulates cell elongation, stem and root growth, seed germination, and dwarf plant development. The interaction with its endogenous ligand GA3 shows a higher affinity energy (\(-9.2\) kcal/mol) than FCF (\(-7.8\) kcal/mol), suggesting that while FCF binds with moderate affinity, it could still activate the receptor. Two of the interacting amino acids are shared between GA3 and FCF (bold in Table 3).  
In contrast, the auxin receptor (IAA7) is associated with polar transport, callus formation, root initiation, delayed leaf abscission, and parthenocarpy induction [42]. The similar binding energies for the endogenous ligand and FCF (\(-5.0\) and \(-5.4\) kcal/mol, respectively) imply that FCF could effectively bind to IAA7, sharing three of the five essential interacting amino acids.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Receptor**} & \multirow{2}{*}{**Ligand**} & \multirow{2}{*}{\begin{tabular}{c} **Affinity Energy** \\ **(kcal/mol)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Amino Acid of** \\ **Interaction** \\ \end{tabular} } \\ \multirow{2}{*}{GA3 Ox2} & GA3 & \(-9.2\) & \begin{tabular}{c} HIS208, **HIS227**, PHE310, THR206, SER230, \\ ARG337, **ILE119**, PRO118, MET334 \\ \end{tabular} \\ \multirow{2}{*}{GA3 Ox2} & FCF & \(-7.8\) & \begin{tabular}{c} ASN210, ARG295, ASP229, **HIS227**, **ILE119**, LEU224, PHE301, SER297, TYR212, VAL236 \\ \end{tabular} \\ \multirow{2}{*}{IAA7} & IAA & \(-5.0\) & \
\begin{tabular}{c} **ARG12**, **LYS13**, PRO6, **ASN10**, TYR11** \\ \end{tabular} \\ \multirow{2}{*}{IAA7} & FCF & \(-5.4\) &
\begin{tabular}{c} **ARG12**, **LYS13**, VAL8, **ASN10** \\ \end{tabular} \\ \hline \hline \end{tabular}  
* **Note:** Endogenous ligands are shaded gray, and repeated amino acids in interactions are highlighted in bold.  
\end{table}
Table 3: Affinity energy and amino acid of interactions from docking GA3 Ox2 and IAA7.  
Figure 7: Docking analysis with the IAA7 receptor. Interaction spheres with (**a**) IAA and (**b**) FCF, and 2D interaction maps with (**c**) IAA and (**d**) FCF.  
FCF shows molecular affinity for both GA3 Ox2 and IAA7 receptors, suggesting its binding to the protein-ligand complex. A molecular dynamics study has been conducted to confirm the stability of the interaction over time.