SaARF7调控生长素介导檀香吸器发育的分子机制

檀香是檀香科的濒危树种，具根半寄生性。营养生长期的檀香需要通过特异的寄生器官-吸器入侵寄主根部组织吸收水分和矿物质维持生长。前期研究表明生长素可诱导吸器提前发育，但调控机制不明。生长素响应因子（ARF）是生长素信号转导途径重要的转录因子，调控多种器官的发育。檀香共有20个ARF蛋白，综合其进化特征、表达模式和对生长素的响应程度，推测SaARF7与半寄生特性有关，可能在生长素介导吸器发育中起到关键的调控作用。因此，本研究拟利用建立的遗传转化体系、原位杂交、液相色谱及转录组等技术在本体开展SaARF7的功能研究；利用染色质免疫沉淀联合组学数据筛选SaARF7下游靶基因；利用酵母单杂和凝胶迁移等技术开展SaARF7和靶基因互作的验证工作，阐明SaARF7调控生长素介导檀香吸器发育的分子机理。研究结果不仅为吸器发育机理研究奠定基础，还为科学制定檀香人工林培育计划提供理论和实践依据。

Sandalwood (Santalum album L.) is an endangered species of the family Santalaceae, with hemi-parasitic root. Sandalwood needs to absorb water and minerals from host roots through specific parasitic organ-haustoria, to maintain sandalwood growth during the vegetative phase of plant development. Our previous studies show auxin can induce haustoria development，but the molecular mechanism underlying haustoria development remains largely unknown. Auxin response factors (ARFs) are important transcription factors involved in auxin signal transduction pathway, which is responsible for ARF various organ development regulation. There are 20 ARF proteins identified in sandalwood genome. We propose that SaARF7 is related to hemi-parasitic characteristics, based on the evolution characteristics, expression pattern and the sensitivity of response of auxin SaARF7 may play an important role in regulating haustoria development mediated by auxin. Therefore, in this study, we plant to systematically study the function of SaARF7 in haustoria development through genetic transformation, in situ hybridization, liquid chromatography and transcriptome technology, etc. SaARF7 target genes screening will be achieved by ChIP-Seq and other techniques like haustoria transcriptome, and the identified SaARF7 and its target interaction will be confirmed by Y1H and EMSA, etc. These data will contribute to our current understanding of the molecular mechanism of SaARF7 regulating haustoria development mediated by auxin. The results not only lay the foundation for the haustoria development mechanism research, but also provide the theory and practice basis for sandalwood plantation cultivation.