环指蛋白RING1与A型核纤层蛋白的细胞内相互作用

环指蛋白RING1能结合DNA并抑制基因的转录.采用酵母双杂交方法从人骨骼肌文库中筛选出了与A型核纤层蛋白(lamin A)结合的RING1蛋白,回复杂交酵母能在缺陷培养基上生长.RING1与绿色荧光蛋白融合载体转染HEK293细胞,激光共聚焦显微观察发现RING1能与带红色荧光蛋白的lamin A蛋白在细胞核周围共定位.免疫共沉淀结果证明RING1与lamin A能够相互作用.结果证明了一个新的lamin A结合蛋白,为揭示lamin A影响基因表达乃至细胞衰老提供了依据.     

A型核纤层蛋白的研究进展

A型核纤层蛋白由LMNA基因编码,为核纤层的主要成分,呈动态网状结构,位于核膜下层,起重要的机械支持作用,直接或间接与染色质相互作用,在维持染色质结构、转录、DNA复制和细胞凋亡等方面发挥重要作用.LMNA基因及其编码蛋白lamin A/C异常能引起一组人类遗传病,称为核纤层蛋白病.为深入了解A型核纤层蛋白的正常生理功能及其在相关核纤层蛋白病中的作用,本文就A型核纤层蛋白的结构分类、修饰组装、动力学、相互作用蛋白及相关核纤层蛋白病等方面进行综述.     

Changes in the photosynthesis properties and photoprotection capacity in rice (Oryza sativa) grown under red,blue, or white light

Photosynthesis Research - Non-photochemical quenching (NPQ) of the excited state of chlorophyll a is a major photoprotective mechanism plants utilize to survive under high light. Here, we report...     

miRNA,lncRNA与心血管疾病

近年来,心血管疾病在我国的发病率和致死率呈逐年上升趋势,已成为威胁我国公众健康的重要疾病之一.尽管长期的研究使人们对心血管疾病有了一定的了解,但是其发病机制尚未完全清楚.非编码RNA(non-coding RNA,ncRNA)是指转录组中不编码蛋白的功能性RNA分子,包括微小RNA(microRNA,miRNA)和长链非编码RNA(long non-coding RNA,lncRNA)等.miRNA是一类在进化上高度保守,具有转录后调节活性的单链非编码小分子RNA.而lncRNA是一类转录本长度超过200个核苷酸的功能性非编码RNA分子.研究表明,这些功能性ncRNA不但在细胞增殖、分化和衰老过程中发挥着重要作用,还参与了癌症、神经退行性疾病和心血管疾病等疾病的病理进程.本文将着重概述miRNA和lncRNA在心血管疾病中的作用及其最新研究进展.     

12个不同基因型冬小麦的光合能力

 研究了12个不同基因型冬小麦(Triticum aestivum)品种(其中两个为北京本地品种)的光合能力。结果表明：小偃22、陕麦897和8907-11-5三个品种的净光合速率超过20μmolCO2·m-2·s-1,均比其它实验品种高,其PSⅡ总的光化学量子产额(Yield)、光化学荧光猝灭系数(qP)和水分利用效率(WUE)也较高;而其暗呼吸速率和非光化学荧光猝灭系数(qN)较低,表现出具有良好的光合生理功能,而且这些参数具有连锁相关的趋势。因此,北京地区要引种外地具有优良光合生理功能的冬小麦作为栽培品种或育种亲本时,在所实验的10个外地品种中,上述3个品种应为首选品种。     

Yeast polyubiquitin gene <Emphasis Type="Italic">UBI4</Emphasis> deficiency leads to early induction of apoptosis and shortened replicative lifespan

Ubiquitin is a 76-amino acid protein that is highly conserved among higher and lower eukaryotes. The polyubiquitin gene UBI4 encodes a unique precursor protein that contains five ubiquitin repeats organized in a head-to-tail arrangement. Although the involvement of the yeast polyubiquitin gene UBI4 in the stress response was reported long ago, there are no reports regarding the underlying mechanism of this involvement. In this study, we used UBI4-deletion and UBI4-overexpressing yeast strains as models to explore the potential mechanism by which UBI4 protects yeast cells against paraquat-induced oxidative stress. Here, we show that ubi4Δ cells exhibit oxidative stress, an apoptotic phenotype, and a decreased replicative lifespan. Additionally, the reduced resistance of ubi4Δ cells to paraquat that was observed in this study was rescued by overexpression of either the catalase or the mitochondrial superoxide dismutase SOD2. We also demonstrated that only SOD2 overexpression restored the replicative lifespan of ubi4Δ cells. In contrast to the case of ubi4Δ cells, UBI4 overexpression in wild-type yeast increases the yeast’s resistance to paraquat, and this overexpression is associated with large pools of expressed ubiquitin and increased levels of ubiquitinated proteins. Collectively, these findings highlight the role of the polyubiquitin gene UBI4 in apoptosis and implicate UBI4 as a modulator of the replicative lifespan.     

Rab4：细胞囊泡循环运输过程的重要因子

囊泡运输是真核细胞中物质运输及信息交流的重要形式,Rab蛋白在这个过程中发挥着重要功能.Rab4是Rab蛋白家族的成员之一,参与调控早期内体的分选与内体循环途径.Rab4包括Rab4A、Rab4B和Rab4C 3个亚型.本文主要阐述了Rab4的结构特征、主要的效应蛋白和参与运输的货物蛋白以及影响细胞自噬、葡萄糖摄取、神经调节、心脏功能及肿瘤发生方面的功能.     

Exploiting the engine of C(4) photosynthesis

Ever since the discovery of C(4) photosynthesis in the mid-1960s, plant biologists have envisaged the introduction of the C(4) photosynthetic pathway into C(3) crops such as rice and soybeans. Recent advances in genomics capabilities, and new evolutionary and developmental studies indicate that C(4) engineering will be feasible in the next few decades. Furthermore, better understanding of the function of C(4) photosynthesis provides new ways to improve existing C(4) crops and bioenergy species, for example by creating varieties with ultra-high water and nitrogen use efficiencies. In the case of C(4) engineering, the main enzymes of the C(4) metabolic cycle have already been engineered into various C(3) plants. In contrast, knowledge of the genes controlling Kranz anatomy lags far behind. Combining traditional genetics, high-throughput sequencing technologies, systems biology, bioinformatics, and the use of the new C(4) model species Setaria viridis, the discovery of the key genes controlling the expression of C(4) photosynthesis can be dramatically accelerated. Sustained investment in the research areas directly related to C(4) engineering has the potential for substantial return in the decades to come, primarily by increasing crop production at a time when global food supplies are predicted to fall below world demand.