类胡萝卜素是小麦营养品质的重要组成部分，而类胡萝卜素合成代谢调控机制的匮乏限制了精准的类胡萝卜素代谢工程的应用进程。项目组前期研究在小麦中干扰TaLCYB基因显著降低了β-胡萝卜素含量，证实该基因是决定小麦籽粒中β-胡萝卜素含量的关键酶基因。进一步研究发现TaLCYB基因的启动子序列含有多个ABA应答元件，TaLCYB的表达显著受ABA信号抑制。因此，我们推测转录调控是ABA信号调控TaLCYB基因表达的重要方式，但具体分子机制仍不清楚。本研究将通过鉴定TaLCYB基因启动子上的ABA响应元件和与其互作的转录因子，研究ABA应答转录因子对TaLCYB基因的调控机理，以期阐明ABA调控TaLCYB基因表达进而影响β-胡萝卜素的含量和总类胡萝卜素积累的分子机制。研究结果将加深对类胡萝卜素合成调控机制的理解，为小麦及其它植物中的类胡萝卜素遗传代谢工程提供理论依据。

Carotenoid is one of the major pigments and determines the nutritional value of wheat. However, the precise carotenoid metabolic engineering in crop plants has been hindered by limited data about the endogenous regulation of carotenogenic genes. Previously, we cloned and characterized the function of TaLCYB in wheat, which was key factor for the β-carotene accumulation in the transgenic wheat due to its high expression. There are several ABRE elements in the promoter of TaLCYB through sequence analysis. The expression of TaLCYB was down-regulated by the ABA treatment. Based on these results, we speculate that transcriptional modulation is crucial for ABA inducing the expression of TaLCYB gene. In this study, we will characterize the ABRE element in the promoter region of TaLCYB gene and their interactive transcription factors, study the roles and mechanisms involved in transcription factors modulating TaLCYB, and elucidate the molecular mechanism underlying ABA modulating the expression of TaLCYB gene to regulate the content of carotenoid. This work will be benefit for improving the understanding of the molecular mechanism of carotenoid regulation, and supply theoretical evidence for carotenoid metabolic engineering in wheat and other crops.