报告题目：MCTP家族蛋白调控拟南芥侧根发育的分子机制研究

报告摘要：

植物激素生长素精准调控植物生长和发育的几乎所有方面。生长素响应因子ARF控制生长素响应基因的转录，可在细胞质中以凝聚物状态存在，亦可以单体形式存在于细胞核。ARF蛋白的核质分布可以调节生长素敏感性并使植物对生长素的响应调节多样化。然而，ARF蛋白核质分布的动态控制很大程度上仍不清楚。本研究表明具有C2结构域和跨膜区域的MCTP家族可调控生长素响应因子ARF蛋白的核质分配，进而决定侧根发育。MCTP蛋白在侧根中高度表达，并与ARF7/19蛋白在细胞质特异性相互作用，使ARF7/19蛋白的胞质凝聚物解聚，促进了ARF7/19蛋白在侧根原基中的核定位与侧根发育。本研究表明MCTP是调节生长素响应的关键开关，并证明了MCTP-ARF信号模块对于植物根系的建立至关重要。

报告人简介：

报告人本科毕业于南京农业大学，2016年在浙江大学获得博士学位。2016-2021年继续在浙江大学从事博士后工作，其中2018-2019年前往新加坡国立大学俞皓院士实验室做访问学者。以第一作者在Developmental Cell、Molecular Plant、Plant Cell and Environment等期刊发表SCI论文6篇,并参与发表多篇论文。主持国家自然科学基金项目、上海市农委科技兴农等项目，并获得浙江省自然科学二等奖。

【所在学科研究组研究方向】：

1. MCTP介导植物生长发育与逆境响应的平衡；
2. 光信号调控的植物生长发育。

【代表性著作】

1. Xuan, L.J., Li J.Y., Jiang Y.P., Shi M.Q., Zhu Y.K., Bao X.R. Gong Q.Q., Xue H-w., Yu H., and Liu L. (2024) MCTP controls nucleocytoplasmic partitioning of auxin response factors during lateral root development. Developmental Cell doi.org/10.1016/j.devcel.2024.09.026.

2. Xuan, L.J., Jiang Y.P., and Liu L. (2022) New insights into temperature-dependent regulation of flowering. Molecular Plant 15(11):1656-1658.

3. Xuan, L.J., Yan, T., Lu, L.Z., Zhao, X.Z., Wu, D.Z., Hua, S.J. and Jiang, L.X. (2019) Genome-wide association study reveals new genes involved in leaf trichome formation in polyploid oilseed rape (Brassica napus L.). Plant Cell and Environment 43(3):675-691

4. Xuan, L.J., Zhang, C.C., Yan, T., Wu, D.Z., Hussain, N., Li, Z.L., Chen, M.X., Pan, J.W., and Jiang, L.X. (2018) TRANSPARENT TESTA 4-mediated flavonoids negatively affect embryo fatty acid biosynthesis in Arabidopsis. Plant Cell and Environment 41(12):2773-2790.

5.Liu L., Xuan, L.J., Jiang Y.P., and Yu H. (2021) Regulation by FLOWERING LOCUS T and TERMINAL FLOWER 1 in flowering time and plant architecture. Small Structures 2(2000125): 1-20

ACADEMIC SALON (LVI)

SPEAKER: Lijie Xuan

                 Assistant Research Fellow, Department of Plant Science, SAB

TIME ：T12:40-14:00 October 30th, 2024 (Wed)

VENUE：Room 201, Building B, SAB

ORGANIZER：Office of Discipline and Science & Technology, SAB;

                        Young Teachers Association, SAB

TITLE：MCTP controls nucleocytoplasmic partitioning of AUXIN RESPONSE FACTORs during lateral root development

ABSTRACT：

The plant hormone auxin orchestrates almost all aspects of plant growth and development. AUXIN RESPONSE FACTORs (ARFs) control the transcription of auxin-responsive genes, forming cytoplasmic condensates to modulate auxin sensitivity and diversify auxin response regulation. However, the dynamic control of ARF distribution across different subcellular compartments remains largely obscure. Here, we show that three MULTIPLE C2 DOMAIN AND TRANSMEMBRANE REGION PROTEINs (MCTPs), MCTP3, MCTP4, and MCTP6, control ARF nucleocytoplasmic partitioning and determine lateral root development. MCTP3/4/6 are highly expressed in lateral roots and specifically interact with ARF7 and ARF19 to dissolve their cytoplasmic condensates. This promotes ARF nuclear localization in lateral root primordia and enhances auxin signaling during lateral root formation. Our findings confer MCTP as a key switch to modulate auxin responses and outline an MCTP-ARF signaling cascade that is crucial for the establishment of the plant root system.