c-Jun,the most extensively studied protein of the activator protein-1(AP-1)complex,is involved in numerous cell activities,such as proliferation,apoptosis,survival,tumorigenesis and tissue morphogenesis.Earlier studie...c-Jun,the most extensively studied protein of the activator protein-1(AP-1)complex,is involved in numerous cell activities,such as proliferation,apoptosis,survival,tumorigenesis and tissue morphogenesis.Earlier studies focused on the structure and function have led to the identification of c-Jun as a basic leucine zipper(bZIP)transcription factor that acts as homo-or heterodimer,binding to DNA and regulating gene transcription.Later on,it was shown that extracellular signals can induce post-translational modifications of c-Jun,resulting in altered transcriptional activity and target gene expression.More recent work has uncovered multiple layers of a complex regulatory scheme in which c-Jun is able to crosstalk,amplify and integrate different signals for tissue development and disease.One example of such scheme is the autocrine amplification loop,in which signal-induced AP-1 activates the c-Jun gene promoter,while increased c-Jun expression feedbacks to potentiate AP-1 activity.Another example of such scheme,based on recent characterization of gene knockout mice,is that c-Jun integrates signals of several developmental pathways,including EGFR-ERK,EGFR-RhoA-ROCK,and activin B-MAP3K1-JNK for embryonic eyelid closure.After more than two decades of extensive research,c-Jun remains at the center stage of a molecular network with mysterious functional properties,some of which are yet to be discovered.In this article,we will provide a brief historical overview of studies on c-Jun regulation and function,and use eyelid development as an example to illustrate the complexity of c-Jun crosstalking with signaling pathways.展开更多
文摘淋巴细胞活化基因3(lymphocyte-activation gene 3,LAG-3)又称CD223,是一种由LAG-3基因编码的含有498个氨基酸的I型穿膜蛋白,由胞外区、穿膜区和胞内区三部分组成。LAG-3主要通过胞外区与配体结合,负向调控T淋巴细胞,避免T细胞过度激活引发自身免疫。与程序性死亡蛋白-1(programmed cell death 1,PD-1)和细胞毒性T淋巴细胞抗原4(cytotoxic T lymphocyte antigen 4,CTLA-4)一样,LAG-3是体内重要的免疫检查点,对人体免疫系统起到平衡调控作用。肿瘤细胞通过高表达LAG-3配体逃避机体免疫系统的监视。随着免疫检查点的研究逐渐深入,LAG-3成为继PD-1和CTLA-4之后新一代的免疫治疗靶点。本文主要对LAG-3的结构、功能及其抑制剂在肿瘤免疫治疗中的应用进行综述,以期为LAG-3的进一步研究提供参考。
文摘c-Jun,the most extensively studied protein of the activator protein-1(AP-1)complex,is involved in numerous cell activities,such as proliferation,apoptosis,survival,tumorigenesis and tissue morphogenesis.Earlier studies focused on the structure and function have led to the identification of c-Jun as a basic leucine zipper(bZIP)transcription factor that acts as homo-or heterodimer,binding to DNA and regulating gene transcription.Later on,it was shown that extracellular signals can induce post-translational modifications of c-Jun,resulting in altered transcriptional activity and target gene expression.More recent work has uncovered multiple layers of a complex regulatory scheme in which c-Jun is able to crosstalk,amplify and integrate different signals for tissue development and disease.One example of such scheme is the autocrine amplification loop,in which signal-induced AP-1 activates the c-Jun gene promoter,while increased c-Jun expression feedbacks to potentiate AP-1 activity.Another example of such scheme,based on recent characterization of gene knockout mice,is that c-Jun integrates signals of several developmental pathways,including EGFR-ERK,EGFR-RhoA-ROCK,and activin B-MAP3K1-JNK for embryonic eyelid closure.After more than two decades of extensive research,c-Jun remains at the center stage of a molecular network with mysterious functional properties,some of which are yet to be discovered.In this article,we will provide a brief historical overview of studies on c-Jun regulation and function,and use eyelid development as an example to illustrate the complexity of c-Jun crosstalking with signaling pathways.
