本课题主攻组织器官生长和尺寸控制的信号基础研究，主要通过遗传学等筛选策略系统鉴定肝、肠等组织器官生长和尺寸控制的关键信号和因子，并利用模式动物、生化结构和高通量测序等前沿技术手段，揭示组织器官生长和尺寸控制过程中关键信号的诱发与转导机制。在课题开展的第三年，本课题组成员在Hippo信号通路调控器官稳态、组织损伤修复及肿瘤生长等方面取得良好进展。一方面解析了Hippo通路核心组分LATS2激酶发生相变的分子生物学基础，发现了该组分相变异常促进肿瘤发生的作用机制；同时逐步阐释了上游调控因子NF2调控TEAD4棕榈酰化修饰的信号机理，及该通路重要细胞核内组分VGLL4参与小肠损伤修复的功能作用。另一方面，借助单细胞测序技术手段系统解析了中性粒细胞在胃癌发生发展过程中的时空异质性，发现了与肿瘤进展及免疫治疗敏感性相关的新型细胞亚型，并深入揭示了YAP/TAZ调控中性粒细胞分化及肿瘤杀伤效应的分子机制，为靶向YAP/TAZ介导的抗肿瘤免疫治疗策略提供了转化基础。此外，本课题组成员还揭示了核膜因子SUN1/2及cGAS等新型因子调控肿瘤等器官尺寸异常疾病的病理机制。最后，正在加速推进肠道类器官研究体系及新型的细胞互作体系的体内外评价，特别是基于邻近标记技术的细胞间直接互作体系取得突破性进展。在此基础上，本课题将继续按照预设目标和进度开展相关功能筛选，发现与肝、肠器官生长和尺寸控制的新型调控因子，揭示这些因子的信号感知及调控机理，为课题二和课题三提供研究基础。The focus of topic one is characterization the signal transduction cascades in mediating the tissue development and organ size control.Specifically,we aim to systemically identify the upstream signals to trigger,as well as the mediators to initiate the activation of Hippo and mTOR signaling,as both of which play crucial roles in tissue development and organ size control.Technically,we will apply a wide range of systems including model organisms,structural biology,and novel sequencing strategies to dissect the underlined mechanisms,providing the comprehensive regulatory network in controlling the organ size of both liver and intestine.On the basis of existing research,with the joint efforts of all researchers,a series of research progress has been made in 2023,and the original scientific research plan has been successfully completed.First,we revealed that LATS2,the core kinase of Hippo pathway,respond to F-actin cytoskeleton reduction and is released from adherens junction to form phase separated condensates in the cytoplasm,providing a compartmentalized and reversible platform for Hippo signaling transduction and protein stability.Moreover,we also dissected the essential roles of Hippo compeonments inlcuding NF2,VGLL4,as well as SUN1/2 and cGAS,in homostasis maintance,tissue damage repair and tumor immunity.On the other hand,we applied scRNA-Seq to decipher the tumor-associated neutrophil heterogeneity in GC,and revealed a neutrophil-specific role of YAP/TAZ signaling in exerting anti-tumor activity,deficiency of which confers resistance to immune blockade therapy.In addition,we have set up several genetic platforms and will start to screen regulators of both liver and intestine development and organ size control in vivo.Taken together,we have fully finished our goals as planned and are moving fast to the next step based on our progresses achieved in first-year.

本年度的研究工作基本按照原定计划开展，在如下各方面取得进展。(1)利用条件性敲除小鼠模型发现COP1促进结肠癌发生发展的功能。(2)发现转录因子ZBTB7B作为新的抑癌基因抑制肝癌发生。(3)发现基底膜蛋白IV型胶原蛋白α5链调控管腔型乳腺癌糖酵解。(4)解析了Hippo信号通路调控肝内胆管癌细胞转分化过程的机制。(5)发现了XAF1与AKT经由转录因子FOXO1的双向负调控机制。(6)解析了Hippo调控因子可与转录因子KLF5与协作促进三阴性乳腺癌中脂质代谢的机制。(7)解析了转录因子IRF4及DNA去甲基化酶NMAD-1的结构基础。The research has been carried out according to the original plan,and significant progress has been made at the following aspects.(1)The oncogenic role of COP1 was analyzed in colorectal cancer with conditional knockout and spontaneous tumor mouse model and patient’s samples.(2)Transcriptional factor ZBTB7B was identified as a tumor suppressor in liver cancer.(3)The mechanism of Basal membrane protein Collagen Alpha-5(IV)chain in regulating glycolysis in luminal breast cancer cells was investigated.(4)The functional mechanisms of Hippo pathway in intrahepatic cholangiocarcinoma cell trans-differentiation were analyzed.(5)We dissected the bi-directional double negative regulation feedback of AKT-FOXO1-XAF1.(6)Detailed mechanisms for lipid metabolism regulation by Hippo co-factors and KLF5 in triple negative breast cancer were analyzed.(7)The structural basis of the function for transcriptional factor IRF4 and DNA demethylase NMAD-1 was revealed.

组织器官生长和尺寸控制的机制是生命科学研究方向的重大问题。本课题聚焦组织器官生长和尺寸控制信号的感知应答与协同调控，致力于解析组织器官生长和尺寸控制过程中细胞如何感知胞内外的关键信号、应答网络、细胞间相互作用、代谢及表观遗传如何与之协同调控细胞增殖与生长等科学问题。课题执行以来，原定计划和研究任务开展顺利，人才培养等考核指标已完成，经本项目资助发表论文五篇，使用斑马鱼、小鼠等多种动物模型详尽回答了肝脏、心脏和胰腺生长发育中和尺寸控制相关的科学问题，对控制器官大小和尺寸的重要信号通路Hippo的上游调控进行了深入的研究，同时开发了新型的细胞谱系追踪技术，为未来相关科研的展开奠定了技术基础。接下来我们将围绕项目原定计划开展研究，保障本课题的顺利实施和完成。How multicellular organisms sense and control their organ size is a fundamental but unanswered question in the current biology research field.This research program focuses on the signaling network for sensing and controlling organ size during tissue growth and organ development and aims to elucidate the underlying mechanism by a series of cooperative research in the signaling pathway,cell-cell interaction,cell proliferation,metabolism,and epigenetics.Until 2022,we have completed the midterm plan and published five research papers with the support of this grant.We elucidated the mechanism of development and size control of liver,heart,and pancreases in zebrafish and mouse models,discovered new regulation mechanism of the Hippo pathway,and developed new cell lineage tracing technique.We will continue the research according to the original proposal.

本课题主攻组织器官生长和尺寸控制的信号基础研究，主要通过遗传学等筛选策略系统鉴定肝、肠等组织器官生长和尺寸控制的关键信号和因子，并利用模式动物、生化结构和高通量测序等前沿技术手段，揭示组织器官生长和尺寸控制过程中关键信号的诱发与转导机制。在课题开展的前两年，本课题组成员在Hippo信号通路调控器官稳态、组织损伤修复及肿瘤生长等方面取得良好进展，共发现5种与Hippo、mTOR等通路相关的组织器官调控因子，并揭示这些因子响应炎症因子、放化疗等刺激条件下调控尺寸信号的分子机制。同时，正在加速推进肠道类器官研究体系及新型的细胞互作体系的体内外评价，特别是基于邻近标记技术的细胞间直接互作体系取得突破性进展。在此基础上，本课题将继续按照预设目标和进度开展相关功能筛选，发现与肝、肠器官生长和尺寸控制的新型调控因子，揭示这些因子的信号感知及调控机理，为课题二和课题三提供研究基础。The focus of topic one is characterization the signal transduction cascades in mediating the tissue development and organ size control.Specifically,we aim to systemically identify the upstream signals to trigger,as well as the mediators to initiate the activation of Hippo and mTOR signaling,as both of which play crucial roles in tissue development and organ size control.Technically,we will apply a wide range of systems including model organisms,structural biology,and novel sequencing strategies to dissect the underlined mechanisms,providing the comprehensive regulatory network in controlling the organ size of both liver and intestine.In the first two years of this five-year project,we achieved great progresses in Hippo signaling regulation at diverse layers and established multiple interrelationships between dysregulation of key factors and diseases.We identified five transcriptional factors related to Hippo or mTOR signaling pathway regulating tissue development and organ size control and deciphered the mechanism.In addition,we have set up several genetic platforms and will start to screen regulators of both liver and intestine development and organ size control in vivo.Taken together,we have fully finished our goals as planned and are moving fast to the next step based on our progresses achieved in these two years.