22 research outputs found
Hippo信号通路:器官大小与组织稳态调控器
复杂机体如何控制器官大小是发育生物学最基本问题之一,其调控机制的解析也是生命科学领域长期存在的一大难题。Hippo信号通路是21世纪初利用果蝇遗; 传学研究发现并命名的,它可以通过调控细胞增殖、凋亡和干细胞的自我更新与分化,在器官大小决定、组织稳态维持与重塑等生命活动过程中发挥关键作用。由于; Hippo信号通路在物种间高度保守,它的发现为人们研究生物个体器官发育大小及再生的调控机制提供了可能,这是利用果蝇遗传学研究解决重大科学问题的又; 一个经典范例。在过去的十几年中,针对Hippo信号通路的研究逐渐成为国际上又一新兴的研究热点
Menin Deficiency Leads to Depressive-like Behaviors in Mice by Modulating Astrocyte-Mediated Neuroinflammation
厦门大学医学院、神经科学研究所张杰教授团队发现了抑郁症新的致病基因MEN1,并阐明了MEN1调控星形胶质细胞炎症导致抑郁发生发展的新机制,为抑郁症的诊治提供了新靶点和方向。抑郁症是严重威胁人类健康的重大神经系统疾病,危及全球30%的人口。但对其发病机制并不清楚。张杰教授团队发现,在慢性不可预测以及LPS处理的模拟抑郁小鼠模型中,多发性内分泌肿瘤蛋白(menin)在大脑中的表达显著降低,并且在星形胶质细胞中降低最明显。为了研究menin是否参与了小鼠抑郁表型的产生,研究团队制作了多种神经系统menin条件性敲除小鼠。通过对这些小鼠行为学的检测,锁定了只有在星形胶质细胞中敲除menin后,小鼠才会表现出抑郁样表型。证实了menin可能是通过调控星形胶质细胞的功能促进了抑郁的发生。
MEN1基因的突变会导致多发性内分泌肿瘤,而内分泌的紊乱和抑郁等精神疾病有着密切的联系。下丘脑-垂体-肾上腺轴(HPA轴)的功能紊乱直接参与了抑郁的产生。基于此研究团队推测MEN1的基因突变是否也会导致抑郁的发生。通过和中国医学科学院基础所的许琪教授合作,研究团队对1000多例重度抑郁患者和800多例对照人群进行了MEN1基因的外显子测序。通过测序发现MEN1的一个SNP s375804228和抑郁的发生有着显著关联。该SNP导致menin第503位的氨基酸由G突变成D。通过功能研究进一步证实该突变可以阻断menin和p65的结合,从而过度激活NF-κB-IL-1β通路,导致神经炎症的发生。
张杰,厦门大学特聘教授、博士生导师。国家优秀青年科学基金;教育部新世纪优秀人才;福建省杰出青年科学基金;厦门市五四青年奖章等获得者。2011年8月加入厦门大学医学院神经科学研究所担任教授至今。张杰博士主要从事重大神经系统疾病(老年痴呆、帕金森、抑郁症、自闭症、术后认知障碍、胶质瘤)等的发病机制和药物开发研究。至今以第一作者或者通讯作者在国际知名期刊发表研究论文21篇。其中回国独立开展研究工作以后,作为通讯作者在 Neuron,Cell Reports, PNAS, The Journal of Neuroscience, Clinical Cancer Research,Cell Death and Disease, JBC, Chemistry,Chem. Biol. Drug Des.等杂志上发表多篇研究论文。【Abstract】Astrocyte dysfunction and inflammation are associated with the pathogenesis of major depressive disorder (MDD). However, the mechanisms underlying these effects remain largely unknown. Here, we found that multiple endocrine neoplasia type 1 (Men1; protein: menin) expression is attenuated in the brain of mice exposed to CUMS (chronic unpredictable mild stress) or lipopolysaccharide. Astrocyte-specific reduction of Men1 (GcKO) led to depressive-like behaviors in mice. We observed enhanced NF-κB activation and IL-1β production with menin deficiency in astrocytes, where depressive-like behaviors in GcKO mice were restored by NF-κB inhibitor or IL-1β receptor antagonist. Importantly, we identified a SNP, rs375804228, in human MEN1, where G503D substitution is associated with a higher risk of MDD onset. G503D substitution abolished menin-p65 interactions, thereby enhancing NF-κB activation and IL-1β production. Our results reveal a distinct astroglial role for menin in regulating neuroinflammation in depression, indicating that menin may be an attractive therapeutic target in MDD.We thank Prof. Guanghui Jin (Xiamen University) and Prof. Xianxin Hua (University of Pennsylvania) for providing the Men1-floxp mice. This work was supported by the National Natural Science Foundation of China (grants 81522016, 81271421, and 31571055 to J.Z.; 81625008 and 31430048 to Q.X.; 81630026 to Z.Y.; 81771163 and U1405222 to H.X.; U1505227 to G.B.; 81472725 to W.M.), the Natural Science Foundation of Fujian Province of China (grant 2013J01147 and 2014J06019 to J.Z.), the Fundamental Research Funds for the Central Universities (grants 20720150062 and 20720180049 to J.Z.), the National Key Research and Development Program of China (2016YFC1305903), and CAMS Innovation Fund for Medical Sciences (grant 2016I2M1004 to Q.X.).研究工作得到国家自然科学基金项目(81522016、81271421、31571055)以及厦门大学校长基金等资助
CDK5-dependent BAG3 degradation modulates synaptic protein turnover
阿尔茨海默病(AD)是严重威胁人类健康的重大神经系统疾病,AD的发生发展与衰老密切相关,目前临床治疗方法十分有限。因此迫切需要从AD致病早期入手,发现和鉴定导致AD神经功能紊乱的机制和靶点,为AD的早期防治提供基础。张杰教授及其团队从高通量磷酸化蛋白质组学入手,系统研究了CDK5在神经细胞中的磷酸化底物,鉴定出了在蛋白质量控制中发挥重要功能的BAG3蛋白是CDK5的全新底物。课题组从磷酸化蛋白质组学入手,发现和阐明了细胞周期蛋白激酶5(CDK5)通过调控BAG3在维持突触蛋白水平调控中的作用机制,及其在阿尔茨海默病(AD)发生发展中的机理。
该研究是多个团队历时8年合作完成的,香港中文大学的周熙文教授、美国匹兹堡大学的Karl Herrup教授、美国Sanford-Burnham研究所的许华曦教授、美国梅奥医学中心的卜国军教授,厦门大学医学院的文磊教授、张云武教授、赵颖俊教授、薛茂强教授,军事医学科学院的袁增强教授等都参与了该工作。
厦门大学医学院2012级博士生周杰超等为文章的第一作者,张杰教授为通讯作者。Background
Synaptic protein dyshomeostasis and functional loss is an early invariant feature of
Alzheimer’s disease (AD), yet the unifying etiological pathway remains largely unknown.
Knowing that cyclin-dependent kinase 5 (CDK5) plays critical roles in synaptic formation
and degeneration, its phosphorylation targets were re-examined in search for candidates with
direct global impacts on synaptic protein dynamics, and the associated regulatory network
was also analyzed.
Methods
Quantitative phospho-proteomics and bioinformatics analyses were performed to identify
top-ranked candidates. A series of biochemical assays were used to investigate the associated
regulatory signaling networks. Histological, electrochemical and behavioral assays were
performed in conditional knockout, shRNA-mediated knockdown and AD-related mice
models to evaluate its relevance to synaptic homeostasis and functions.
Results
Among candidates with known implications in synaptic modulations, BCL2-associated
athanogene-3 (BAG3) ranked the highest. CDK5-mediated phosphorylation on
Ser297/Ser291 (Mouse/Human) destabilized BAG3. Loss of BAG3 unleashed the selective
protein degradative function of the HSP70 machinery. In neurons, this resulted in enhanced
degradation of a number of glutamatergic synaptic proteins. Conditional neuronal knockout of
Bag3 in vivo led to impairment of learning and memory functions. In human AD and
related-mouse models, aberrant CDK5-mediated loss of BAG3 yielded similar effects on
synaptic homeostasis. Detrimental effects of BAG3 loss on learning and memory functions
were confirmed in these mice, and such were reversed by ectopic BAG3 re-expression.
Conclusions
Our results highlight that neuronal CDK5-BAG3-HSP70 signaling axis plays a critical
role in modulating synaptic homeostasis. Dysregulation of the signaling pathway directly
contributes to synaptic dysfunction and AD pathogenesis.This work was supported by the National Science Foundation in China (Grant: 31571055, 81522016, 81271421 to J.Z.; 81801337 to L.L; 81774377 and 81373999 to L.W.); Fundamental Research Funds for the Central Universities of China-Xiamen University (Grant: 20720150062, 20720180049 and 20720160075 to J.Z.); Fundamental Research Funds for Fujian Province University Leading Talents (Grant JAT170003 to L.L); Hong Kong Research Grants Council (HKUST12/CRF/13G, GRF660813, GRF16101315, AoE/M-05/12 to K.H.; GRF16103317, GRF16100718 and GRF16100219 to H.-M,C.); Offices of Provost, VPRG and Dean of Science, HKUST (VPRGO12SC02 to K.H.); Chinese University of Hong Kong (CUHK) Improvement on Competitiveness in Hiring New Faculty Funding Scheme (Ref. 133), CUHK Faculty Startup Fund and Alzheimer’s Association Research Fellowship (AARF-17-531566) to H.-M, C.
该研究受到了国家自然科学基金、厦门大学校长基金、福建省卫生教育联合攻关基金等的资助
中国海及邻近区域碳库与通量综合分析
中国海总面积约470万平方公里,纵跨热带、亚热带、温带、北温带等多个气候带.其中,南海北依\"世界第三极\"青藏高原、南邻\"全球气候引擎\"西太平洋暖池,东海拥有全球最宽的陆架之一,跨陆架物质运输显著,黄海是冷暖流交汇区域,渤海则是受人类活动高度影响的内湾浅海.中国海内有长江、黄河、珠江等大河输入,外邻全球两大西边界流之一的黑潮.这些鲜明的特色赋予了中国海碳储库和通量研究的典型代表意义.文章从不同海区(渤海、黄海、东海、南海)、不同界面(陆-海、海-气、水柱-沉积物、边缘海-大洋等),以及不同生态系统(红树林、盐沼湿地、海草床、海藻养殖、珊瑚礁、水柱生态系统等)多层面对海洋碳库与通量进行了较系统地综合分析,初步估算了各个碳库的储量与不同碳库间的通量.就海气通量而言,渤海向大气中释放CO2约0.22Tg Ca-1,黄海吸收CO2约1.15Tg Ca-1,东海吸收CO2约6.92~23.30Tg Ca-1,南海释放CO2约13.86~33.60Tg Ca-1.如果仅考虑海-气界面的CO2交换,中国海总体上是大气CO2的\"源\",净释放量约6.01~9.33Tg Ca-1.这主要是由于河流输入以及邻近大洋输入所致.河流输入渤黄海、东海、南海的溶解无机碳(DIC)分别为5.04、14.60和40.14Tg Ca-1,而邻近大洋输入DIC更是高达144.81Tg Ca-1,远超中国海向大气释放的碳量.渤海、黄海、东海、南海的沉积有机碳通量分别为2.00、3.60、7.40、7.49Tg Ca-1.东海和南海向邻近大洋输送有机碳通量分别为15.25~36.70和43.39Tg Ca-1.就生态系统而言,中国沿海红树林、盐沼湿地、海草床有机碳埋藏通量为0.36Tg Ca-1,海草床溶解有机碳(DOC)输出通量为0.59Tg Ca-1;中国近海海藻养殖移出碳通量0.68Tg Ca-1,沉积和DOC释放通量分别为0.14和0.82Tg Ca-1.总计,中国海有机碳年输出通量为81.72~103.17Tg Ca-1.中国海的有机碳输出以DOC形式为主,东海向邻近大洋输出的DOC通量约15.00~35.00Tg Ca-1,南海输出约31.39Tg Ca-1.综上,尽管从海-气通量看中国海是大气CO2的\"源\",但考虑了河流、大洋输入、沉积输出以及微型生物碳泵(DOC转化输出)作用后,中国海是重要的储碳区.需要指出的是,文章数据是基于中国海各海区碳循环研究报道,鉴于不同研究方法上的差异,所得数据难免有一定的误差范围,亟待将来统一方法标准下的更多深入研究和分析.国家重点研发计划项目(编号:2016YFA0601400);;国家自然科学基金项目(批准号:91751207、91428308、41722603、41606153、41422603);;中央高校基础研究项目(编号:20720170107);;中海油项目(编号:CNOOC-KJ125FZDXM00TJ001-2014、CNOOCKJ125FZDXM00ZJ001-2014)资
重离子注入生物材料质量沉积效应评述
前人曾用重离子束注入生物小分子 ,借助先进的仪器分析手段 ,对重离子注入质量沉积进行了初步研究 ,但质量沉积对处于生命状态下的活生物体组织细胞和生物大分子所带来的生物学效应 ,即质量沉积效应的研究还未见报道。将来可用放射性重离子束注入活细胞和生物分子 ,借助放射自显影示踪、放射性测量和分子生物学等研究技术对重离子注入质量沉积效应开展进一步研
