Signal Transduction in Immunocytes

Inflammation Research -     

整合素及其信号传导通路

整合素是位于细胞表面的重要黏附分子,通过其双向信号传导通路,介导细胞与细胞外基质及细胞与细胞间的黏附。整合素由胞外域、跨膜域和胞内域3部分组成。胞内域与细胞内信号分子结合,启动胞内-胞外信号传导激活整合素,提高与相应配体亲合力。而胞外域与相应配体结合后,通过胞外-胞内信号传导,调节细胞生存、增殖、黏附、分化功能。近年研究显示,整合素结构功能及信号传导通路异常与多种疾病有关。     

Signal Transduction and Targeted Therapy

正Springer-nature is announcing the call for submissions for the new open access journal Signal Transduction and Targeted Therapy. The journal will go live on www.nature.com/sigtrans.Signal Transduction and Targeted Therapy aims to publish original research articles and review articles related to     

PB1结构域与细胞信号转导

PB1(Phox and Bem1)结构域是一种约由80个氨基酸残基组成的功能性结构域,主要有3种类型。它存在于许多信号转导蛋白中,并介导这些蛋白之间的二聚化。这些PB1结构域蛋白主要参与两条信号转导通路,即丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路和细胞核因子κB(NF-κB)信号通路。同时,PB1结构域与许多肿瘤如乳腺癌、肺癌的发生发展密切相关。     

Wnt抑制因子-1与Wnt通路和肿瘤发生

Wnt抑制因子-1(WntInhibitoryFactor-1,WIF-1)是近年发现的一种Wnt信号抑制分子。WIF-1的结构已基本清楚,其在生物体内的分布因种属和不同发育时期而异。目前认为,WIF-1可能是Wnt的负反馈调节因子,它可与WNT蛋白直接结合并阻断Wnt信号的传递,而Wnt信号也可通过反馈机制对WIF-1的表达和分布进行调节。研究证实,Wnt通路紊乱可引起肿瘤,在多种存在Wnt通路紊乱的肿瘤中均存在WIF-1表达下调或缺失,WIF-1表达下调的原因是由于wif-1基因启动子区发生高甲基化,采用去甲基化等方法恢复WIF-1的正常表达后可抑制相关肿瘤细胞的生长,甚至导致凋亡。     

细胞信号转导与可变剪接调控

大多数真核基因能够发生可变剪接,其调控对于生理和病理状态下细胞功能的实现至关重要,而异常可变剪接则可导致多种疾病.虽然已知可变剪接能够在转录后水平调节基因表达,然而目前仍不清楚特定的可变剪接模式是如何被调控的.越来越多的研究发现细胞信号和外界环境刺激能够调控靶基因的剪接模式,并且已发现一些与可变剪接调控有关的信号转导通路,而后者能够通过修饰剪接因子进而改变剪接因子的亚细胞定位或者活性,从而实现对靶基因可变剪接模式的调控.由细胞信号转导通路所构成的网络能够灵活多样地调控基因剪接,一条信号通路可调控多个基因剪接,而多条信号通路也可调控同一基因剪接,对于理解信号转导过程的分子机制具有重要意义.     

Signal Transduction via MHC Class-I Molecules in T cells

The data reviewed in this paper, suggest that besides their role in presentation of antigenic pcptides to T cells, MHC-I molecules may play an important role in the fine-tuning of signal transmission across the cell membrane by their associations with a variety of cell-surface receptors regulating cell growth and differentiation.     

Defective Calcium-Dependent Signal Transduction in T Lymphocytes of Ataxia-Telangiectasia

T-cell functions of two patients with ataxia-telangiectasia were investigated. Patients with ataxia-telangiectasia had reduced percentages of circulating CD3⁺ cells and CD4⁺ cells, although neither patient had a reduced percentage of circulating CD8⁺ cells. The proliferative responses and interleukin-2 production of peripheral blood mononuclear cells to T-cell mitogens were reduced in the patients. The intracellular calcium concentration in T cells or CD4⁺ cells from both patients was only slightly increased after phytohaemagglutinin stimulation. Moreover, the concentration after OKT3 stimulation was not or only slightly increased in T cells or CD4⁺ cells from both patients. Our results suggest that the functional defect of T cells is caused by defective Ca²⁺-dependent signal transduction through the CD3 complex of the surface in T cells of ataxia-telangiectasia.     

肝纤维化中星状细胞信号转导通路

肝星状细胞活化增殖是肝纤维化发生的关键。肝星状细胞在活化增殖过程中受多种细胞因子或蛋白的调控,通过表面受体激活信号转导网络系统,促使肝纤维化的发生发展。这些表面受体和信号转导通路成为研究的靶向,为纤维化的发生和逆转提供理论依据。     

胃泌素的生物活性及其信号传导通路

胃泌素 (Gastrin)是一种由消化道G细胞分泌的胃肠激素 ,对调节消化道功能和维持其结构完整具有重要作用。通过对其信号传导机制的研究 ,将有助于我们了解其生物学活性的本质。胃泌素是一类主要由胃肠道G细胞合成、释放的肽类激素。胃泌素的合成经历了前胃泌素 (progastrin)、甘氨酸延伸型胃泌素(glycine extendedgastrin ,G Gly)和成熟胃泌素 (gastrinamide)三个阶段。前两种胃泌素是胃泌素合成、加工过程中的中间产物 ,是未酰氨化的胃泌素 (non amidatedgastrin ,NAG) ,而成熟胃泌素是酰氨化胃泌素 (amidatedgastrin)。胃泌素家族成员既有各自的生物学活性 ,彼此之间也相互协调促进 ,共同发挥功能。众多学者对胃泌素发挥生物作用的细胞内信号传导通路进行了广泛而深入的研究。本文就胃泌素的合成释放、生物活性及信号传导通路作一综述。