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去乙酰化酶（HDAC）活性在囊性纤维化（CF）中的作用的特别关注，基于我们在上一个资助期（2010年至2014年）的实质性进展。CF是一种遗传性功能丧失疾病，主要由囊性纤维化跨膜传导调节因子（CFTR）（简称F508del）的Phe508缺失引起。我们现在开始认识到许多其他突变在提供合成，折叠，运输和稳定性/功能途径方面的重要性，这些将在HDAC7的去乙酰化（“橡皮擦”）生物学在纠正F508del中的竞争性更新中得到解决。CFTR是一个多膜跨越，camp调节的氯离子通道。F508del的错误折叠和许多其他突变体一样，减少了CFTR的合成、折叠、运输和/或稳定性/功能，导致细胞表面电导丧失，过早肺衰竭和寿命缩短。因此，CF是一种蛋白质静止生物学疾病，正如我们在之前的资助期和过去所证明的那样。蛋白质静止是维持蛋白质组正常细胞功能的细胞环境。它经常通过多种信号通路进行调节，以保护细胞在短暂的损伤和对遗传性、慢性错误折叠疾病的反应中免受蛋白质折叠应激的影响。这种竞争性更新的重点是通过理解HDAC7去乙酰化功能来寻求CF的纠正。在上一次资助期间，我们提供了证据，证明hdac，特别是HDAC7，可以通过多种途径发挥控制作用-转录，翻译和/或共/翻译后程序，这些程序通过乙酰化/去乙酰化途径与蛋白质组的不同组分相关联。这些可以共同作用，以实现F508del的一定程度的稳定性和功能，从而保护和纠正CF。在这里，我们提出了一个可行的工作假设，即野生型（WT）和F508del CFTR的稳定性和功能受到HDAC7脱乙酰活性网络的强烈影响，该网络通过转录、翻译和/或共同/翻译后机制来指导蛋白质功能。并且可以操纵HDAC7特异性网络，为临床CF提供保护环境。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间产生的HDAC7相互作用组所揭示的新靶点的作用，这些靶点可能负责HDAC7在CF纠正中的功能；目的2侧重于了解HDAC7在（重新）平衡参与纠正CF变异的乙酰化-去乙酰化途径中的作用的方法。联合Aims将提供系统的方法来解决HDAC7调控的影响F508del合成、折叠、运输和细胞表面稳定性/功能的途径。他们将深入研究由HDAC7调控的周期性乙酰化-去乙酰化环境，这可能在临床上纠正CF疾病

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