ARF family identification in <i>Tamarix chinensis</i> reveals the salt responsive expression of <i>TcARF6</i> targeted by miR167
Youju Ye, Jianwen Wang, Wei Wang, Li‐an Xu
Abstract
Auxin response factors ( ARF s) are important transcription factors (TFs) that are differentially expressed in response to various abiotic stresses. The important roles of ARF s and small RNA- ARF pathways in mediating plant growth and stress responses have emerged in several recent studies. However, no studies on the involvement of ARF s in tamarisk trees, which are resistant to salinity, have been conducted. In this study, systematic analysis revealed 12 TcARF genes belonging to five different groups in Tamarix chinensis . The microRNA response elements of miR160, which belongs to group I and miR167, which belongs to group III, were conserved in terms of their location and sequence. Moreover, digital gene expression profiles suggested that a potential miR167 target gene, TcARF6 , was rapidly expressed in response to salt stress. Cloning of TcARF6 revealed that TcARF6 could be an activation TF with a glutamine-rich region and expression pattern analysis revealed that the expression of TcARF6 was significantly downregulated specifically in the roots. A significant negative correlation in the expression pattern of tch-miR167/ TcARF6 indicated that this module may play a key role in the response to salt stress. Overall, these results provide basic information on the posttranscriptional regulation of TcARF6 for future investigations of the T. chinensis salt-stress response.