Isocitrate dehydrogenase (IDH) mutations as drivers of organelle stress and dysfunction"

异柠檬酸脱氢酶 (IDH) 突变是细胞器应激和功能障碍的驱动因素"

基本信息

批准号：
10653827
负责人：
Christal Dyane Sohl
金额：
$ 37.63万
依托单位：
SAN DIEGO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2025-06-30
项目状态：
未结题

项目摘要

ABSTRACT/SUMMARY The consequences of mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 in cancer are unusual. Though these mutations confer a loss of function of the normal activity of the NADP+-dependent conversion of isocitrate to α-ketoglutarate (αKG), mutant IDH is more of an oncogene than tumor suppressor, as a neomorphic activity is also conferred: the NADPH-dependent production of oncometabolite D-2-hydroxyglutarate (D2HG) from αKG. D2HG inhibits αKG-dependent enzymes like DNA and histone demethylases, and NADPH depletion results in oxidative stress. A variety of point mutations affecting residue R132 in IDH1 can grant these catalytic properties, causing prominent structural modifications that allow mutant IDH1 to be a bona fide drug target. Indeed, a se- lective allosteric mutant IDH1 inhibitor is now in the clinic. Both mutant and WT IDH1 localize to the cytosol and peroxisomes, while IDH2 is found in the mitochondria, raising the possibility of organelle-specific consequences of IDH mutations, though this has not yet been explored. Interestingly, there is a communication pipeline between the peroxisomes and mitochondria in that they share an interconnected role in lipid processing and mitigation of oxidative stress, though the role of IDH in this communication is not yet known. To date, several limitations have restricted the rigor of mutant IDH studies. First, the catalytic and inhibition profile for R132H IDH1 is extrapolated to other disease-relevant IDH1 mutants, though we show several mutants have very unique profiles. Second, the role of NADPH depletion, and thus oxidative stress, is often overlooked in favor of studying consequences of D2HG. Third, studies focus on the global/cytosolic contributions of mutant IDH1, ignoring its role of sole NADPH and αKG producer in this organelle. However, we report evidence of dysfunctional lipid biosynthetic pathways in the peroxisomes upon introduction of cellular IDH1 mutations. The overall goal of our research program is to determine the mechanisms of metabolic enzyme catalysis, regulation, inhibition, and cellular/orga- nellular function in health and disease, from the chemical to the cellular levels. By leveraging kinetic, structural, cellular, and -omics technologies, we can establish the unique consequences of disease-relevant mutational variants in metabolic enzymes. Here, we have identified critical questions to illuminate the role of mutant IDH1 in disease: 1) How do protein dynamics affect IDH1 catalysis and inhibition? 2) What are the effects of oxidative stress on IDH1 and IDH2? 3) What are the organelle-specific consequences of IDH1 mutations? 4) What are the roles of IDH1 mutations in organelle crosstalk? Through this work, we will uncover fundamental catalytic and regulatory strategies affecting WT and mutant IDH activity, determine the role of IDH1 in the peroxisomes and identify the unique consequences of mutation at this location, and establish the role of mutant IDH1 in facilitating peroxisomal/mitochondrial lipid biosynthesis and oxidative stress signalling. Upon completing this work we will generate valuable new tools, and identify pathways or mechansims that may be therapeutically targetable.

摘要/总结异柠檬酸脱氢酶 1 (IDH1) 和 IDH2 突变对癌症的影响并不常见。这些突变导致 NADP+ 依赖性异柠檬酸转化的正常活性功能丧失对于 α-酮戊二酸 (αKG)，突变 IDH 作为一种新形态活性，更像是一种癌基因，而不是抑癌基因还被赋予：从 αKG 依赖 NADPH 产生致癌代谢物 D-2-羟基戊二酸 (D2HG)。 D2HG 抑制 αKG 依赖性酶，如 DNA 和组蛋白去甲基酶，NADPH 耗尽会导致影响 IDH1 中残基 R132 的各种点突变可以赋予这些催化特性，显着的结构修饰使突变 IDH1 成为真正的药物靶标。选择性变构突变 IDH1 抑制剂现已投入临床，突变型和 WT IDH1 均定位于细胞质。过氧化物酶体，而 IDH2 存在于线粒体中，增加了细胞器特异性后果的可能性 IDH 突变，尽管尚未对此进行探索。过氧化物酶体和线粒体，因为它们在脂质加工和缓解中具有相互关联的作用氧化应激，尽管 IDH 在这种通讯中的作用尚不清楚，但迄今为止仍存在一些局限性。首先，推断 R132H IDH1 的催化和抑制特性。与其他疾病相关的 IDH1 突变体相比，尽管我们发现一些突变体具有非常独特的特征。 NADPH 消耗的作用以及氧化应激常常被忽视，以利于研究后果第三，研究重点是突变 IDH1 的整体/胞质贡献，忽略了其唯一的作用。然而，我们报告了生物脂质合成功能障碍的证据。引入细胞 IDH1 突变后过氧化物酶体中的通路我们研究的总体目标。计划的目的是确定代谢酶催化、调节、抑制和细胞/有机的机制从化学到细胞水平，通过利用动力学、结构、细胞和组学技术，我们可以确定与疾病相关的突变的独特后果在这里，我们确定了阐明突变 IDH1 作用的关键问题。疾病中：1) 蛋白质动力学如何影响 IDH1 催化和抑制 2) 氧化的影响是什么？ IDH1 和 IDH2 的压力？ 3) IDH1 突变的细胞器特异性后果是什么？ IDH1 突变在细胞器串扰中的作用？通过这项工作，我们将揭示基本的催化和作用。影响 WT 和突变 IDH 活性的调控策略，确定 IDH1 在过氧化物酶体中的作用和确定该位置突变的独特后果，并确定突变 IDH1 在促进过氧化物酶体/线粒体脂质生物合成和氧化应激信号传导完成后，我们将。产生有价值的新工具，并确定可能具有治疗目标的途径或机制。

项目成果

期刊论文数量（3）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Capturing the Dynamic Conformational Changes of Human Isocitrate Dehydrogenase 1 (IDH1) upon Ligand and Metal Binding Using Hydrogen-Deuterium Exchange Mass Spectrometry.

使用氢-氘交换质谱法捕获配体和金属结合时人异柠檬酸脱氢酶 1 (IDH1) 的动态构象变化。

DOI：
10.1021/acs.biochem.2c00636
发表时间：
2023
期刊：
Biochemistry
影响因子：
2.9
作者：
Sabo,KaitlynA;Albekioni,Elene;Caliger,Danielle;Coleman,NalaniJ;Thornberg,Ella;AvellanedaMatteo,Diego;Komives,ElizabethA;Silletti,Steve;Sohl,ChristalD
通讯作者：
Sohl,ChristalD

Probing altered enzyme activity in the biochemical characterization of cancer.

DOI：
10.1042/bsr20212002
发表时间：
2022-02-25
期刊：
Bioscience reports
影响因子：
4
作者：
Adam MAA;Sohl CD
通讯作者：
Sohl CD

The Effects of Prune Extract on Cellular Models of Bone Cancer.

西梅提取物对骨癌细胞模型的影响。

DOI：
发表时间：
2022
期刊：
FASEB journal : official publication of the Federation of American Societies for Experimental Biology
影响因子：
0
作者：
Miller,Chelsie;Adam,Mowaffaq;Chao,Grace;Hooshmand,Shirin;Sohl,Christal
通讯作者：
Sohl,Christal