CaDoF10, a DNA-binding with one finger transcription factor from pepper, act as a positive regulator of cold stress...

DNA-binding with one finger (DoF) transcription factors in plants have been reported to be induced under cold stress. However, the role of DoFs in pepper (Capsicum annuum L.) under cold stress has not been fully explored. In this study, the expression analysis of 33 CaDoFs revealed that multiple CaDoFs were upregulated under cold stress. CaDoF10 showed markedly higher expression at all time points under cold stress in compared to other CaDoFs. In addition, CaDoF10 shared the highest homology with AtDoF1, which has been reported to be involved in cold stress response in Arabidopsis. Therefore, CaDoF10 was selected as a candidate gene to examine its role in cold stress response in pepper. Silencing of CaDoF10 resulted in reduced expression of the cold marker genes CaCBF1A and CaRD29A, and increased cold sensitivity in the silenced plants compared with the control. Furthermore, analysis of physiological attributes and antioxidant enzyme activities revealed reduced cold tolerance in CaDoF10-silenced plants compared with the control. On the other hand, overexpression of CaDoF10 in the transgenic Arabidopsis lines conferred improved tolerance to cold stress. Overall, the results of this study suggest that CaDoF10 acts as a positive regulator of the cold stress response, offering a potential target for genetic improvement of stress resilience in pepper.