Epigenomic Modulation of Cystic Fibrosis

描述（由申请人提供）：本次竞争性更新保留了其对组蛋白脱乙酰酶（HDAC）活性在囊性纤维化（CF）中的作用的具体关注，建立在我们在上一个资助期（2010年至2014年）的实质性进展基础上。CF是一种遗传性功能丧失性疾病，主要由囊性纤维化跨膜传导调节因子（CFTR）中的Phe 508缺失（称为F508 del）引起。我们现在开始认识到许多其他突变在提供对合成、折叠、运输和稳定性/功能途径的见解方面的重要性，这些途径将在这种竞争性更新中得到解决，该竞争性更新集中在HDAC 7在校正F508 del中的脱乙酰化（“擦除器”）生物学上。CFTR是跨多膜的cAMP调节的氯离子通道。F508 del和可能的许多其他突变体的错误折叠减少CFTR的合成、折叠、运输和/或稳定性/功能，导致细胞表面电导损失、过早肺衰竭和寿命缩短。因此，CF是一种蛋白质代谢停滞生物学疾病，正如我们在上一个资助期和过去所证明的那样。蛋白质稳态是维持蛋白质组用于正常细胞功能的细胞环境。它经常使用多种信号通路进行调节，以保护细胞在短暂损伤期间免受蛋白质折叠应激，并响应遗传性慢性错误折叠疾病。这种竞争性更新的主旨是通过理解HDAC 7脱乙酰化功能来寻求CF的校正。在上一个资助期间，我们提供的证据表明HDAC，特别是HDAC 7，可以通过多种途径发挥控制作用-转录，翻译和/或共翻译/翻译后程序，这些程序通过乙酰化/脱乙酰化途径与蛋白质组的不同组分相关联。这些可以一起操作，以实现F508 del的稳定性和功能水平，可以保护和纠正CF。在本文中，我们建议关注使能工作假设，即野生型（WT）和F508 del CFTR的稳定性和功能受到HDAC 7脱乙酰化活性网络的强烈影响，所述HDAC 7脱乙酰化活性网络通过转录、翻译和/或共翻译/翻译后机制来指导蛋白质功能，并且HDAC 7特异性网络可以被操纵以在临床中为CF提供保护性环境。为了探索我们的工作假设，我们提出了两个目标：目标1侧重于了解在上一个资助期内产生的HDAC 7相互作用组揭示的新靶点的作用，这些靶点可能负责HDAC 7在校正CF中的功能;目标2侧重于了解HDAC 7在（重新）平衡校正CF变体所涉及的乙酰化-脱乙酰化途径中的作用的方法。合并的目的将提供系统的方法来解决影响F508 del合成，折叠，运输和细胞表面稳定性/功能的HDAC 7调节途径。它们将提供与HDAC 7调节的循环乙酰化-脱乙酰化环境的深入联系，这可能是临床上CF疾病的矫正方法。

DESCRIPTION (provided by applicant): This competitive renewal retains its specific focus on the role of histone deacetylase (HDAC) activity in cystic fibrosis (CF), building on our substantia progress in the last funding period (2010 to 2014). CF is an inherited loss-of-function disease caused principally by a Phe508 deletion in the cystic fibrosis transmembrane conductance regulator (CFTR), referred to as F508del. We are now beginning to appreciate the importance of many other mutations in providing insights into synthesis, folding, trafficking and stability/function pathways that will be addressed in this competitive renewal focused on the deacetylation ('eraser') biology of HDAC7 in correcting F508del. CFTR is a multi-membrane spanning, cAMP-regulated chloride channel. Misfolding of F508del, and likely many other mutants, reduce the synthesis, folding, trafficking and/or stability/function of CFTR resulting in the loss of cell surface conductance, premature lung failure and shortened lifespan. As such, CF is a disease of proteostasis biology as we have demonstrated under auspices of the previous funding period and in the past. Proteostasis is the cellular environment that maintains the proteome for normal cellular function. It is frequently adjusted using multiple signaling pathways to protect the cell from protein folding stress during transient insult and in response to inherite, chronic misfolding diseases. The thrust of this competitive renewal is to seek correction of CF through an understanding HDAC7 deacetylation function. During the last funding period we provided evidence that HDACs, particularly HDAC7, can exert control through multiple avenues- transcriptional, translational and/or co-/post-translational programs that are linked to different components of the proteome through acetylation/deacetylation pathways. These can operate together to achieve a level of stability and function of F508del that can be protective and corrective for CF. Herein, we propose to focus on the enabling working hypothesis that the stability and function of wild-type (WT) and F508del CFTR is strongly influenced by the HDAC7 network of deacetylation activities that operate through transcriptional, translational and/or co-/post-translational mechanisms to direct protein function, and that the HDAC7 specific network can be manipulated to provide a protective environment for CF in the clinic. To explore our working hypothesis, we propose two aims: Aim 1 focuses on understanding the role of new targets revealed by the HDAC7 interactome generated during the last funding period that are likely responsible for HDAC7 function in correction of CF; Aim 2 focuses on approaches to understand the role of HDAC7 in (re)balancing acetylation-deacetylation pathways involved in correcting CF variants. The combined Aims will provide systematic approach to address HDAC7 regulated pathways affecting F508del synthesis, folding, trafficking and stability/function at the cell surface. They will provide an in-depth link to the cyclical acetylation- deacetylation environments regulated by HDAC7 that may be corrective for CF disease in the clinic