脑缺氧缺血后激活的信号转导通路

 脑缺氧缺血后,神经元和星形胶质细胞中调节细胞存活与死亡的信号转导通路被激活,主要包括：MAPK信号转导通路,PI3-K/Akt信号转导通路,JAK-STAT信号转导通路和转录因子NF- κB参与的信号转导通路等.在缺氧缺血的神经元和星形胶质细胞中,同一信号转导通路的激活表现出不同的时程变化,作用也不尽相同,这可能是这两种细胞对抗缺氧缺血损伤能力差异的基础.深入分析比较信号转导通路的细节差异,将为我们理解损伤/保护机理,寻求保护神经细胞的策略提供实验依据     

真核生物的MAPK级联信号传递途径

MAPK级联途径在真核生物细胞的信号传递过程中起着重要的作用.MAPK级联途径由MAPK、MAPKK和MAPKKK三类酶蛋白组成.这三类蛋白质的结构非常保守,通过磷酸化作用传递各种信号.在酵母和动、植物细胞中已经发现了一系列的MAPK级联途径成员,使真核生物的信号传递途径逐渐得到阐明.     

Histidine Phosphotransfer Proteins in Fungal Two-Component Signal Transduction Pathways

The histidine phosphotransfer (HPt) protein Ypd1 is an important participant in the Saccharomyces cerevisiae multistep two-component signal transduction pathway and, unlike the expanded histidine kinase gene family, is encoded by a single gene in nearly all model and pathogenic fungi. Ypd1 is essential for viability in both S. cerevisiae and in Cryptococcus neoformans. These and other aspects of Ypd1 biology, combined with the availability of structural and mutational data in S. cerevisiae, suggest that the essential interactions between Ypd1 and response regulator domains would be a good target for antifungal drug development. The goal of this minireview is to summarize the wealth of data on S. cerevisiae Ypd1 and to consider the potential benefits of conducting related studies in pathogenic fungi.     

G蛋白及其偶联信号传导途径的研究进展

G蛋白偶联信号传导系统是一类重要的细胞跨膜信号传导途径之一。在有关生化及药理的医学研究中发现许多药剂都是通过G蛋白偶联信号传导途径对动物起作用的。对G蛋白结构与功能的系统研究是新型药剂研制与开发的基础。G蛋白在物种进化过程中具有高度保守性,植物和昆虫中的G蛋白及其偶联组份研究将有助于明确作物抗病虫机理以及昆虫毒理。     

生长因子及细胞因子的两条重要信号转导通路

业已发现的大部分生长因子受体具有酪氨酸激酶活性,其信号传递以Ras通路为主;而多数细胞因子受体本身缺乏酪氨酸激酶活性,其信号传递过程通过JAKs及STATs两个重要的蛋白质家族的介导得以实现．信号转导通路的研究,对于认识各种生长因子及细胞因子的作用机制具有重要意义．     

Calmodulin-Mediated Signal Transduction Pathways in Arabidopsis Are Fine-Tuned by Methylation

Calmodulin N-methyltransferase (CaM KMT) is an evolutionarily conserved enzyme in eukaryotes that transfers three methyl groups to a highly conserved lysyl residue at position 115 in calmodulin (CaM). We sought to elucidate whether the methylation status of CaM plays a role in CaM-mediated signaling pathways by gene expression analyses of CaM KMT and phenotypic characterization of Arabidopsis thaliana lines wherein CaM KMT was overexpressed (OX), partially silenced, or knocked out. CaM KMT was expressed in discreet spatial and tissue-specific patterns, most notably in root tips, floral buds, stamens, apical meristems, and germinating seeds. Analysis of transgenic plants with genetic dysfunction in CaM KMT revealed a link between the methylation status of CaM and root length. Plants with suppressed CaM methylation had longer roots and CaM KMT OX lines had shorter roots than wild type (Columbia-0). CaM KMT was also found to influence the root radial developmental program. Protein microarray analyses revealed a number of proteins with specificity for methylated forms of CaM, providing candidate functional intermediates between the observed phenotypes and the target pathways. This work demonstrates that the functionality of the large CaM family in plants is fine-tuned by an overarching methylation mechanism.     

植物对盐胁迫响应的信号转导途径

植物通过调控复杂的信号网络来应对盐胁迫。近年来,随着植物基因工程技术的发展,对植物在盐胁迫下信号转导系统的研究取得了一定进展。本文以拟南芥为代表,对盐胁迫下参与调控植物耐盐生理响应的两大类主要信号转导途径——Ca2＋依赖型信号转导通路和丝裂原活化蛋白激酶（MAPK）级联反应途径的研究进展进行综述,主要介绍参与各信号转导通路的组件及诱发的耐盐生理响应等方面,并对该研究领域存在的问题及今后可能的研究方向进行展望。     

雌激素受体介导的快速信号通路的研究进展

除了经典的基因组效应以外,雌激素还可以通过细胞内信号转导途径在几分钟甚至是几秒钟内产生快速生物学效应,被称为雌激素的非基因组效应.这种雌激素的非基因组效应与基因组效应一样,也存在着组织、细胞的特异性.本文将对雌激素膜受体存在的依据、以膜ER为核心的多分子复合物的特性及其介导的信号通路以及雌激素快速生物学效应的组织/细胞特异性作一综述.     

Arabidopsis Contains at Least Four Independent Blue-Light-Activated Signal Transduction Pathways

We have investigated the stomatal and phototropic responses to blue light of a number of single and double mutants at various loci that encode proteins involved in blue-light responses in Arabidopsis. The stomatal responses of light-grown mutant plants (cry1, cry2, nph1, nph3, nph4, cry1cry2, and nph1cry1) did not differ significantly from those of their wild-type counterparts. Second positive phototropic responses of etiolated mutant seedlings, cry1, cry2, cry1cry2, and npq1-2, were also similar to those of their wild-type counterparts. Although npq1 and single and double cry1cry2 mutants showed somewhat reduced amplitude for first positive phototropism, threshold, peak, and saturation fluence values for first positive phototropic responses of etiolated seedlings did not differ from those of wild-type seedlings. Similar to the cry1cry2 double mutants and to npq1-2, a phyAphyB mutant showed reduced curvature but no change in the position or shape of the fluence-response curve. By contrast, the phototropism mutant nph1-5 failed to show phototropic curvature under any of the irradiation conditions used in the present study. We conclude that the chromoproteins cry1, cry2, nph1, and the blue-light photoreceptor for the stomatal response are genetically separable. Moreover, these photoreceptors appear to activate separate signal transduction pathways.     

MAPKs信号通路在动脉粥样硬化发生发展中的调控作用

丝裂原激活蛋白激酶(mitogen-activated protein kinases,MAPKs)信号通路是生物体内重要的信号传导通路,其主要参与调控细胞的增殖、生长、分化、凋亡和炎症反应等多种生理病理过程。MAPKs信号通路在多种心血管疾病的病理过程中起着重要调控作用。动脉粥样硬化(athrosclerosis,AS)所致的各种急重症严重危害人类的健康,发病率呈逐年上升的趋势,但是动脉粥样硬化发生发展的分子机制尚不完全清楚。近年来,MAPKs信号通路在动脉粥样硬化(athrosclerosis,AS)的发生发展中的作用已成为是研究的热点。     

罂粟科植物自交不亲和反应中信号转导的研究进展

自交不亲和性是植物特异性地识别并拒绝自花或亲缘关系很近的花粉的一种遗传机制,该特异性受S基因座控制.在前人的研究基础上总结了罂粟科植物自交不亲和反应过程中信号转导的研究进展,将参与其信号级联反应的信号分子分为与S-位点连锁(包括花柱S-蛋白和花粉S-受体)和不连锁的信号分子(Ca2+、p26、p68、MAPK、细胞骨架以及PCD),并综述了各个信号分子之间的相互作用.     

植物中丛枝菌根形成的信号途径研究进展

丛枝菌根(arbuscular mycorrhizal, AM)共生是丛枝菌根真菌与大多数陆地植物的根系之间形成的一种互利共生关系。植物给菌根真菌提供碳水化合物; 作为回报, 菌根真菌能够增强植物对矿质营养元素(尤其是磷)的吸收。菌根的形成过程是一系列信号交换和转导的结果, 具有严格并且一致的顺序。本文以植物中菌根形成的信号途径为主线, 对菌根真菌的形成过程和信号转导途径及其方式进行了分析和讨论。高等植物中菌根形成的信号途径与豆科植物的结瘤信号途径部分共享, 并且与钙离子信号途径相关, 但前者更为广泛。尽管该途径中很多过程目前还不十分清楚, 但是相信在不久的将来就可以揭开菌根形成过程中的众多谜团。     

植物中丛枝菌根形成的信号途径研究进展

丛枝菌根(arbuscular mycorrhizal,AM)共生是丛枝菌根真菌与大多数陆地植物的根系之间形成的一种互利共生关系。植物给菌根真菌提供碳水化合物;作为回报,菌根真菌能够增强植物对矿质营养元素(尤其是磷)的吸收。菌根的形成过程是一系列信号交换和转导的结果,具有严格并且一致的顺序。本文以植物中菌根形成的信号途径为主线,对菌根真菌的形成过程和信号转导途径及其方式进行了分析和讨论。高等植物中菌根形成的信号途径与豆科植物的结瘤信号途径部分共享,并且与钙离子信号途径相关,但前者更为广泛。尽管该途径中很多过程目前还不十分清楚,但是相信在不久的将来就可以揭开菌根形成过程中的众多谜团。     

Environmental Sensing and Signal Transduction Pathways Regulating Morphopathogenic Determinants of Candida albicans

Candida albicans is an opportunistic fungal pathogen that is found in the normal gastrointestinal flora of most healthy humans. However, under certain environmental conditions, it can become a life-threatening pathogen. The shift from commensal organism to pathogen is often correlated with the capacity to undergo morphogenesis. Indeed, under certain conditions, including growth at ambient temperature, the presence of serum or N-acetylglucosamine, neutral pH, and nutrient starvation, C. albicans can undergo reversible transitions from the yeast form to the mycelial form. This morphological plasticity reflects the interplay of various signal transduction pathways, either stimulating or repressing hyphal formation. In this review, we provide an overview of the different sensing and signaling pathways involved in the morphogenesis and pathogenesis of C. albicans. Where appropriate, we compare the analogous pathways/genes in Saccharomyces cerevisiae in an attempt to highlight the evolution of the different components of the two organisms. The downstream components of these pathways, some of which may be interesting antifungal targets, are also discussed.