Kaijie Zhu, first author of “Regulation of carotenoid and chlorophyll pools in hesperidia, anatomically unique fruits found only in Citrus“
Current Position: Job hunting
Education: Ph.D., Huazhong Agricultural University (HZAU), China.
Non-scientific Interests: Reading, traveling, and swimming
Brief bio: In 2013, I joined the Xiuxin Deng’ lab in the Huazhong Agricultural University (HZAU), China, and started my graduate study. With the guidance of Prof. Xiuxin Deng and other teachers in our lab, I mainly work on the project “Color Variation of Navel Orange Flavedo and Regulatory Analysis of Lycopene β-cyclase”. Domesticated citrus varieties are woody perennials and interspecific hybrid crops of global economic and nutritional importance. The citrus fruit “hesperidium” is a unique morphological innovation not found in any other plant lineage. We investigated the molecular basis of the Citrus sinensis brown flavedo mutation, which conditions flavedo that is brown instead of orange. We used a multi-omics approach to collect data from several genetic sources and plant chimeras, to successfully decipher this mutation, and further studies revealed the underlying regulatory mechanisms responsible for the temporal control of chlorophyll degradation and carotenoid biosynthesis during citrus fruit development. In addition, we are also interested in the enzyme activity diversity of chromoplast-specific lycopene β-cyclase (LCYb2) alleles, which are closely associated with the formation of citrus red traits. Some critical transcription factors that directly regulating CsLCYb2 were screened, and their functions were explored. The above studies were published in Plant Physiology, Journal of Experimental Botany, Journal of Agricultural and Food Chemistry, Phytochemistry, and Horticultural Plant Journal. The economic and nutritional value of citrus makes these findings of wide interest. The novel strategy implemented, and the results obtained, constitute an advance for agro-industry by driving opportunities for citrus crop improvement.
科研经历简介：2013年进入华中农业大学邓秀新院士课题组开启硕博连读生涯。在邓老师和课题组其他老师的悉心指导下我主要研究柑橘果实色泽变异及其调控，研究课题为“脐橙果皮色泽变异及番茄红素β-环化酶的调控研究”。柑橘类水果在世界上的种植面积和产量均居第一位，具有重要的经济价值和营养价值。柑果是芸香科柑橘属植物特有的果实类型，具有区别与其它果实的独特的形态学特征。我们一方面以新发掘的脐橙果皮色泽突变体‘宗橙’为材料，对其棕色果皮表型及其主要品质性状进行了精细分析，采用多组学和多种遗传资源整合策略挖掘到其突变位点，并结合生化手段解析了该突变体果皮叶绿素降解受阻和类胡萝卜素积累增加的突变机制。另一方面我们探究了柑橘红色性状形成关键基因——有色体特异表达番茄红素β-环化酶（LCYb2）的等位基因酶活差异，筛选到直接调控CsLCYb2 的关键转录因子，并对它们进行了系统地功能分析。上述研究初步解析了柑果类果实叶绿素和类胡萝卜素代谢的协同调控机制，为未来柑橘育种提供了重要理论依据。主要研究结果以第一或者共一作者身份发表在Plant Physiology，Journal of Experimental Botany，Journal of Agricultural and Food Chemistry，Phytochemistry，Horticultural Plant Journal等杂志上。