A bHLH transcription factor from Chenopodium glaucum confers drought tolerance to transgenic maize by positive regulation of morphological and physiological performances and stress-responsive genes’ expressions

The basic helix-loop-helix (bHLH) transcription factor has been shown to play an important role in various physiological processes. However, its functions and mechanisms in drought tolerance still remain poorly understood. Here, we reported a bHLH transcription factor — CgbHLH001 — from Chenopodium glaucum, which was able to confer drought tolerance in maize. CgbHLH001-overexpressed maize lines exhibited drought-tolerant phenotype and improved ear traits by accumulating the contents of soluble sugar and proline and elevating the activities of antioxidant enzymes (SOD, POD, and CAT) under drought stress, accompanying with the upregulation of some stress-related genes, which may balance the redox and osmotic homeostasis compared with the non-transgenic and CgbHLH001-RNAi plants. These findings suggest that CgbHLH001 can confer drought tolerance and has the potential for utilization in improving drought resistance in maize breeding.