Control of cell cycle checkpoint mediated by mammalian target of rapamycin

雷帕霉素哺乳动物靶标介导的细胞周期检查点的控制

基本信息

批准号：
10680609
负责人：
YONEZAWA Kazuyoshi
金额：
$ 2.11万
依托单位：
Kobe University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10680609/
关键词：
amino acid leucine mitogen rapamycin mTOR protein synthesis p70 S6 kinase eIF4E binding protein インスリン mTORキナーゼ細胞増殖 eIF-4E BP-1

项目摘要

Rapamycin is a lipophilic macrolide compound and binds to FKBP12 in mammalian cells. The mTOR (mammalian target of rapamycin) protein was identified as a target of FKBP12-rapamycin complex. This protein has a calculated molecular weight of 289 kDa and contains a kinase-like domain at its carboxyl-terminus. In this study, we obtained following findings.(1)mTOR participates in nutrient-sensing, especially amino acid-sensing, in mammalian cells and regulates translational effectors, such as p70S6 kinase α (p70α) and eIF4E binding protein (4EBP).(2)Activation of amino acid-mTOR signaling pathway is indispensable for mitogen-induced protein synthesis. In other words, amino acid-mTOR signaling is a priming signal for mitogen-induced protein synthesis.(3)Among amino acids, leucine has the most potent ability to activate phosphorylation of p70α.(4)p70α, extracted in inactive forms from rapamycin-treated cells, can be directly phosphorylated by the mTOR kinase at the rapamycin-sensitive site Thr-412. mTOR-catalyzed p70α phosphorylation in vitro is accompanied by a substantial restoration in p70α kinase activity.(5)Sequential phosphorylation of p70α by mTOR and 3-phosphoinositide-dependent protein kinase 1 in vitro results in a synergistic stimulation of p70α activity to levels similar to that attained by serum stimulation in vivo.(6)Several candidates of binding partners of mTOR were identified using conventional biochemical methods and yeast-two hybrid system and detailed analyses are now in progress.(7)Some of leucine derivatives were found to have the ability to inhibit p70α activation and T cell proliferation. This analysis is also now in progress.

雷帕霉素是一种亲脂性大环内化合物，与哺乳动物细胞中的FKBP12结合。 MTOR（雷帕霉素的哺乳动物靶标）蛋白被鉴定为FKBP12-宽霉素复合物的靶标。该蛋白质的分子量为289 kDa，并在其羧基末端包含一个类似激酶的结构域。在这项研究中，我们获得了遵循发现。（1）MTOR参与哺乳动物细胞中的营养 - 氨基酸 - 氨基酸 - 敏感性，并调节翻译作用，例如p70s6激酶α（p70α）（p70α）和eIF4E EIF4E结合蛋白（4EEBP）（4EEBP）。 other words, amino acid-mTOR signaling is a priming signal for mitogen-induced protein synthesis.(3)Among amino acids, leucine has the most potential ability to activate phosphorylation of p70α.(4)p70α, extracted in active forms from rapamycin-treated cells, can be directly phosphorylated by the mTOR kinase at the rapamycin-sensitive site Thr-412. MTOR催化的p70α磷酸化体外伴随着p70α激酶活性中的二次恢复。（5）MTOR对p70α的顺序磷酸化，MTOR和3-磷酸固醇依赖性的蛋白依赖性蛋白激酶1中的几个刺激在Viv刺激中，在Viv刺激中，在Viv刺激中，在Viv刺激中相似。使用常规的生化方法和酵母 - 两种混合动力系统鉴定了MTOR结合伙伴的候选者，现在正在进行详细的分析。（7）发现某些亮氨酸衍生物具有抑制p70α激活和T细胞增殖的能力。该分析也正在进行中。