ADENYLYL CYCLASE BY ADENOSINE 3'-PHOSPHATES

3-磷酸腺苷产生腺苷酸环化酶

基本信息

批准号：
6634929
负责人：
Roger A Johnson
金额：
$ 40.95万
依托单位：
STATE UNIVERSITY NEW YORK STONY BROOK
依托单位国家：
美国
项目类别：
财政年份：
1986
资助国家：
美国
起止时间：
1986-09-01 至 2005-03-31
项目状态：
已结题

项目摘要

DESCRIPTION (Verbatim from Applicant's Abstract): Adenylyl cyclases are central to one of the most important transmembrane signal transduction pathways in virtually all biological systems and constitute a family of isozymes catalyzing the formation of adenosine 3': 5'-monophosphate (cAMP) from 5'ATP. Mammalian forms of the enzyme are stimulated or inhibited by hormones via G-protein-linked cell-surface receptors and are inhibited by intracellular adenine nucleoside 3'-phosphates via an enzyme conformation that is distinct from that through which catalysis occurs. The proposal is based on observations made with and unique applications for conformation-specific inhibitors of adenylyl cyclases we have synthesized: a) competitive inhibitors targeting the pre-transition, catalytically competent conformation, exemplified by b-L-2',3'-dideoxyadenosine-5'-triphosphate (IC50 about 24nM), and b) non-competitive inhibitors targeting the post-transition product leaving conformation, exemplified by 2',5'-dideoxyadenosine-3'-triphosphate (IC50 about 40nM). The goals of the proposed investigations include: i) to use these ligands and derivatives of them to define structural differences between pre- and post-transition configurations of adenylyl cyclase and differences among selected wild type and mutated adenylyl cyclase isozymes, by biochemical and biophysical techniques; ii) to establish in intact cells and tissues the consequences of adenylyl cyclase inhibition by prodrug derivatives of these nucleotides; iii) to identify and quantify naturally occurring adenine nucleoside 3'-polyphosphates and to identify the pathways of their synthesis and degradation; and iv) to isolate other enzymes through which they may act to alter cell function. The proposed approaches build on the applicant's experience with adenylyl cyclases, with its regulation by adenine nucleotides, and with the synthesis of unique, labeled and unlabeled nucleotide derivatives targeted to specific configurations of this key transmembrane signal transduction enzyme. The proposed studies will provide unique ligands and approaches to address key questions regarding the structure and regulation of adenylyl cyclases, will establish previously unexplored links between cell-initiated regulation of adenylyl cyclases and 3'-nucleotide metabolism, and will lead to the identification of other target proteins with which adenine nucleoside 3'-polyphosphates interact and regulate.

描述（逐字研究来自申请人的摘要）：腺苷酸循环酶是中心到最重要的跨膜信号转导通路之一几乎所有生物系统，构成同工酶催化的家族腺苷3'：5'ATP的形成5'ATP。哺乳动物酶的形式被激素通过 G蛋白连接的细胞表面受体，细胞内抑制腺嘌呤核苷3'-磷酸盐通过酶构象不同由此通过催化。该提案基于观察与特定于构象特异性抑制剂的独特应用我们已经合成的腺苷酸循环酶：a）针对的竞争性抑制剂预先过渡，催化胜任构象，例证了 B-l-2'，3'-二氧添加性5'-三磷酸（IC50约24nm），B），B）针对过渡后产品的非竞争性抑制剂离开构象，以2'，5'-二氧乙烯果碱-3'-triphosphate（关于IC50的IC50）为例 40nm）。拟议调查的目标包括：i）使用这些它们的配体和衍生物是定义前的结构差异和腺苷环酶的过渡后配置以及之间的差异通过生化和生物物理技术； ii）在完整的细胞和组织中建立前药衍生物抑制腺苷酸环化酶的后果核苷酸； iii）识别和量化天然存在的腺嘌呤核苷3'-聚球并识别其合成的途径和退化； iv）隔离其他酶，它们可以采取行动改变单元功能。拟议的方法建立在申请人的基础上具有腺苷循环酶的经验，并由腺嘌呤核苷酸调节，并合成独特，标记和未标记的核苷酸衍生物针对此关键跨膜信号的特定配置转导酶。拟议的研究将提供独特的配体，并解决有关结构和调节的关键问题的方法 adenylyl循环酶将建立以前未开发的链接细胞引发的腺苷酸环酶和3'-核苷酸代谢的调节，并将导致鉴定腺嘌呤的其他靶蛋白核苷3'-聚磷酸盐相互作用并调节。