BET bromodomain inhibitors PFI-1 and JQ1 are identified in an epigenetic compound screen to enhance C9ORF72 gene expression and shown to ameliorate C9ORF72-associated pathological and behavioral abnormalities in a C9ALS/FTD model.
BET bromodomain inhibitors PFI-1 and JQ1 are identified in an epigenetic compound screen to enhance C9ORF72 gene expression and shown to ameliorate C9ORF72-associated pathological and behavioral abnormalities in a C9ALS/FTD model.
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DOI：
10.1186/s13148-021-01039-z
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发表时间：
2021-03-16
影响因子：
5.7
通讯作者：
van Zundert B
中科院分区：
文献类型：
--
作者：
Quezada E;Cappelli C;Diaz I;Jury N;Wightman N;Brown RH Jr;Montecino M;van Zundert B
C9 ORF 72基因中的内含子GGGGCC（G4 C2）六核苷酸重复扩增（HRE）是肌萎缩侧索硬化（ALS）和额颞叶痴呆（FTD）的最常见原因，称为C9 ALS/FTD。C9 ALS/FTD尚无治愈或有效治疗方法。出现了三种主要分子机制来解释C9 ALS/FTD疾病机制：（1）通过单倍不足导致的C9 ORF 72功能丧失，（2）通过重复RNA翻译导致的二肽重复（DPR）蛋白介导的毒性，以及更有争议的，（3）通过形成核内RNA灶的重复双向转录导致的RNA介导的毒性。最近的研究表明，C9 ALS/FTD存在双重致病机制，其中C9 ORF 72蛋白水平降低导致毒性DPR清除受损。在此，我们探讨了药理学化合物是否可以在体外逆转这些病理学特征和在C9 ALS/FTD小鼠模型（C9 BAC）中逆转认知障碍。我们特别关注我们的研究针对染色质调节蛋白（tumerin-regulating proteins，tumerrugs）的小分子抑制剂，目的是增加C9 ORF 72基因表达并减少毒性DPR。我们生成了含有10个（对照）或≥ 90个（突变体）G4 C2 HRE的荧光素酶报告细胞系，这些HRE位于人C9 ORF 72基因的外显子1a和1b之间。在靶向溴结构域、染色质结构域和组蛋白修饰酶的14种不同受体的筛选中，我们发现几种溴结构域和末端外结构域（BET）抑制剂（BETi），包括PFI-1和JQ 1，增加了荧光素酶报告基因活性。使用来自C9 BAC小鼠的原代皮质培养物，我们进一步发现PFI-1处理增加了人突变C9 ORF 72基因的V1-V3转录物的表达，减少了聚（GP）-DPR包涵体，但增强了核内RNA灶。我们还测试了JQ 1（一种先前显示通过腹膜内（i. p.）注射，可以恢复C9 BAC小鼠的行为异常。有趣的是，发现JQ 1给药（每天腹膜内给药，持续7天）挽救了C9 BAC小鼠中的海马依赖性认知缺陷。我们的发现将BET布罗莫结构域抑制剂作为C9 ALS/FTD的潜在疗法，通过改善C9 ORF 72相关的病理和行为异常。我们的发现，PFI-1增加积累的核内RNA灶是在最近的数据在苍蝇表明，核RNA灶可以是神经保护的螯合重复转录，导致有毒的DPR的协议。在线版本包含补充材料，可通过10.1186/s13148-021-01039-z获得。
An intronic GGGGCC (G4C2) hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), referred to as C9ALS/FTD. No cure or effective treatment exist for C9ALS/FTD. Three major molecular mechanisms have emerged to explain C9ALS/FTD disease mechanisms: (1) C9ORF72 loss-of-function through haploinsufficiency, (2) dipeptide repeat (DPR) proteins mediated toxicity by the translation of the repeat RNAs, and more controversial, (3) RNA-mediated toxicity by bidirectional transcription of the repeats that form intranuclear RNA foci. Recent studies indicate a double-hit pathogenic mechanism in C9ALS/FTD, where reduced C9ORF72 protein levels lead to impaired clearance of toxic DPRs. Here we explored whether pharmacological compounds can revert these pathological hallmarks in vitro and cognitive impairment in a C9ALS/FTD mouse model (C9BAC). We specifically focused our study on small molecule inhibitors targeting chromatin-regulating proteins (epidrugs) with the goal of increasing C9ORF72 gene expression and reduce toxic DPRs. We generated luciferase reporter cell lines containing 10 (control) or ≥ 90 (mutant) G4C2 HRE located between exon 1a and 1b of the human C9ORF72 gene. In a screen of 14 different epidrugs targeting bromodomains, chromodomains and histone-modifying enzymes, we found that several bromodomain and extra-terminal domain (BET) inhibitors (BETi), including PFI-1 and JQ1, increased luciferase reporter activity. Using primary cortical cultures from C9BAC mice, we further found that PFI-1 treatment increased the expression of V1-V3 transcripts of the human mutant C9ORF72 gene, reduced poly(GP)-DPR inclusions but enhanced intranuclear RNA foci. We also tested whether JQ1, an BETi previously shown to reach the mouse brain by intraperitoneal (i.p.) injection, can revert behavioral abnormalities in C9BAC mice. Interestingly, it was found that JQ1 administration (daily i.p. administration for 7 days) rescued hippocampal-dependent cognitive deficits in C9BAC mice. Our findings place BET bromodomain inhibitors as a potential therapy for C9ALS/FTD by ameliorating C9ORF72-associated pathological and behavioral abnormalities. Our finding that PFI-1 increases accumulation of intranuclear RNA foci is in agreement with recent data in flies suggesting that nuclear RNA foci can be neuroprotective by sequestering repeat transcripts that result in toxic DPRs. The online version contains supplementary material available at 10.1186/s13148-021-01039-z.
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影响因子：
17.1
作者：
Burberry A;Suzuki N;Wang JY;Moccia R;Mordes DA;Stewart MH;Suzuki-Uematsu S;Ghosh S;Singh A;Merkle FT;Koszka K;Li QZ;Zon L;Rossi DJ;Trowbridge JJ;Notarangelo LD;Eggan K
通讯作者：
Eggan K
影响因子：
16.2
作者：
Ash PE;Bieniek KF;Gendron TF;Caulfield T;Lin WL;Dejesus-Hernandez M;van Blitterswijk MM;Jansen-West K;Paul JW 3rd;Rademakers R;Boylan KB;Dickson DW;Petrucelli L
通讯作者：
Petrucelli L
选择性抑制BET溴结构域。
影响因子：
64.8
作者：
通讯作者：
--
影响因子：
12.7
作者：
Cooper-Knock J;Higginbottom A;Stopford MJ;Highley JR;Ince PG;Wharton SB;Pickering-Brown S;Kirby J;Hautbergue GM;Shaw PJ
通讯作者：
Shaw PJ
影响因子：
7.1
作者：
Frick P;Sellier C;Mackenzie IRA;Cheng CY;Tahraoui-Bories J;Martinat C;Pasterkamp RJ;Prudlo J;Edbauer D;Oulad-Abdelghani M;Feederle R;Charlet-Berguerand N;Neumann M
通讯作者：
Neumann M