FUNCTION OF AN INTERFERON INDUCED UBIQUITIN HOMOLOG

干扰素诱导的泛素同系物的功能

基本信息

批准号：
6920554
负责人：
ARTHUR L HAAS
金额：
$ 1.26万
依托单位：
LSU HEALTH SCIENCES CENTER
依托单位国家：
美国
项目类别：
财政年份：
1992
资助国家：
美国
起止时间：
1992-04-01 至 2006-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6920554
关键词：
biological signal transduction chemical conjugate enzyme mechanism gene induction /repression interferons mass spectrometry posttranslational modifications protein isoforms protein localization protein protein interaction protein sequence protein structure function proteomics tissue /cell culture transfection ubiquitin yeast two hybrid system

项目摘要

DESCRIPTION (adapted from applicant's abstract): Interferons induce broad pleiotropic effects including growth inhibition, antitumor activity, hematopoietic regulation, control of cellular/humoral immune responses, and activity against viral and parasitic infection, accounting for interest in these cytokines as potential therapeutic agents. The induction of the ISG15 gene to generate the 17.1 kDa polypeptide ISG15 is one of the earliest responses to Type 1 interferons. ISG15 (formerly termed UCRP, the Ubiquitin Cross Reactive Protein) is the archetype of a recently discovered class of ubiquitin-like proteins that appear to regulate cellular function rather than to target susceptible proteins for degradation by the 26S proteasome. In contrast to the other ubiquitin-like proteins, ISG15 is not present in lower eukaryotes and thus represents a relatively recent evolutionary divergence. The biological effects of ISG15 are exerted through its covalent ligation to a small population of cellular targets that is distinct from those targeted by other ubiquitin-like proteins. Two-hybrid screens have recently identified a small class of highly conserved late interferon-induced proteins collectively termed the 1-8 family. The ca 14 kDa polypeptides bear remarkable yet cryptic sequence similarity to the conserved catalytic domain of ubiquitin conjugating enzymes (Ubc). The present proposal comprises three specific aims. Specific Aim 1 will test the hypothesis that 1-8 isoforms represent ISG15-specific conjugating enzymes through in vitro assays and stable cell transfections of active and dominant mutant forms of the polypeptides. Other studies will concentrate on functional differences among the different isoforms with respect to potential substrate specificity and cellular localization. Specific Aim 2 will focus on the 9-27/Leu13 isoform and its role in transducing antiproliferative and homotypic adhesion signals. Other studies will map protein-protein interaction motifs between 9-27 and the ubiquitous tetraspanin CD81 and their functional interactions with CD19-CD21. Specific Aim 3 will exploit recent advances in proteomics and mass spectroscopic protein fingerprinting to identify time-dependent changes in populations of targets for ISG15 conjugation in quiescent and interferon induced states. These studies are the first concerted functional survey of ISG15 conjugation and the enzymology of this modification.

描述（改编自申请人的摘要）：干扰素引起广泛多效性影响包括生长抑制，抗肿瘤活性，造血调节，控制细胞/体液免疫反应以及针对病毒和寄生虫感染的活动，考虑到兴趣这些细胞因子是潜在的治疗剂。 ISG15的诱导基因生成17.1 kDa多肽ISG15是最早的对1型干扰素的响应。 ISG15（以前称为UCRP，泛素交叉反应性蛋白）是最近发现的一类的原型泛素样蛋白似乎调节细胞功能，而不是靶向26S蛋白酶体降解易感蛋白。在与其他泛素样蛋白形成鲜明对比，ISG15不存在于较低真核生物，因此代表了相对较新的进化差异。这 ISG15的生物学作用是通过其共同结扎与A施加的少量的细胞靶标不同于针对的靶标其他类似泛素的蛋白质。两个杂交屏幕最近已经确定了一小部分高度保守的晚期干扰素诱导的蛋白称为1-8家族。 CA 14 kDa多肽具有显着而神秘的序列与泛素结合的保守催化结构域相似酶（UBC）。本提案包括三个具体目标。具体目标 1将检验1-8同工型代表ISG15特异性的假设通过体外测定和稳定的细胞转染结合酶的共轭酶多肽的活性和显性突变形式。其他研究也会专注于不同同工型之间的功能差异潜在的底物特异性和细胞定位。具体目标2 将重点放在9-27/LEU13同工型上，及其在传输中的作用抗增生和同型粘附信号。其他研究将映射蛋白质 - 蛋白质相互作用基序在9-27和无处不在的四叠腺苷之间 CD81及其与CD19-CD21的功能相互作用。具体的目标3将利用蛋白质组学和质谱蛋白的最新进展指纹识别以确定目标人群的目标变化 ISG15静止和干扰素诱导状态中的共轭。这些研究是 ISG15共轭和酶学的首次协同功能调查此修改。