MYB转录因子介导FHT调控马铃薯块茎愈伤的分子机制研究

愈伤是马铃薯块茎的重要采后特性，通过在伤口表面积累软木脂可有效抑制块茎失水、减轻病原物的侵染。脂肪ω-羟基酸/脂肪醇羟基肉桂酰转移酶（FHT）参与催化软木脂单体的交联，马铃薯StFHT在块茎愈伤中的功能已被证实，但相关转录调控机制尚不明确。我们近期研究发现，马铃薯MYB24和MYB144显著激活了StFHT启动子活性，是参与调控块茎愈伤过程中软木脂积累的关键转录因子。本项目拟在前期工作基础上，采用酵母单杂交、凝胶阻滞等方法深入分析StMYB24/144对StFHT的转录调控方式。进一步利用转基因技术结合采后病理学、生物化学等方法，鉴定马铃薯StMYB24和StMYB144在块茎愈伤中的功能，并分析二者是否存在功能的冗余或互补。旨在阐明MYB参与调控马铃薯块茎愈伤的分子机制，为利用生物技术手段调控马铃薯采后愈伤过程提供新理论。

Wound healing is an important postharvest characteristic of potato tuber. The accumulation of suberin on the wound surface can effectively inhibit the tuber from losing water and reduce the infection of pathogen. Fatty ω-hydroxyacid/fatty alcohol hydroxycinnamoyl transferase (FHT) could catalyze the cross-linking of suberin monomers and the role of StFHT in potato tuber wound healing has been demonstrated. However, the transcriptional regulation mechanism is still unclear. Recently, we found that potato MYB24 and MYB144 significantly activated the StFHT promoter, which should be key transcription factors in regulating the suberin accumulation during tuber wound healing. On the basis of previous results, this project intends to deeply analyse the transcriptional regulation of StMYB24/144 on StFHT by Yeast one hybrid and EMSA. The functions of StMYB24 and StMYB144 during tuber wound healing are further identified by transgenic technology combined with postharvest pathology and biochemistry. Furthermore, the redundant or complementary functional relationship between StMYB24 and StMYB144 is also analyzed. The purpose of this study is to elucidate the MYB regulatory mechanism in potato tuber wound healing, which will provide a new theory for the regulation of potato postharvest wound healing by biotechnology.