The Department of Comparative Medicine, University of Washington, Seattle, Washington, United States of America.
Genomics and Bioinformatics Shared Resources, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America.
PLoS One. 2018 Jun 13;13(6):e0197973. doi: 10.1371/journal.pone.0197973. eCollection 2018.
Birt-Hogg-Dube' Syndrome (BHDS) is a rare genetic disorder in humans characterized by skin hamartomas, lung cysts, pneumothorax, and increased risk of renal tumors. BHDS is caused by mutations in the BHD gene, which encodes for Folliculin, a cytoplasmic adapter protein that binds to Folliculin interacting proteins-1 and -2 (Fnip1, Fnip2) as well as the master energy sensor AMP kinase (AMPK). Whereas kidney-specific deletion of the Bhd gene in mice is known to result in polycystic kidney disease (PKD) and renal cell carcinoma, the roles of Fnip1 in renal cell development and function are unclear. In this study, we utilized mice with constitutive deletion of the Fnip1 gene to show that the loss of Fnip1 is sufficient to result in renal cyst formation, which was characterized by decreased AMPK activation, increased mTOR activation, and metabolic hyperactivation. Using RNAseq, we found that Fnip1 disruption resulted in many cellular and molecular changes previously implicated in the development of PKD in humans, including alterations in the expression of ion and amino acid transporters, increased cell adhesion, and increased inflammation. Loss of Fnip1 synergized with Tsc1 loss to hyperactivate mTOR, increase Erk activation, and greatly accelerate the development of PKD. Our results collectively define roles for Fnip1 in regulating kidney development and function, and provide a model for how loss of Fnip1 contributes to PKD and perhaps renal cell carcinoma.
Birt-Hogg-Dube 综合征 (BHDS) 是一种罕见的人类遗传性疾病,其特征为皮肤错构瘤、肺囊肿、气胸和肾肿瘤风险增加。BHDS 是由 BHD 基因突变引起的,该基因编码滤泡素,一种细胞质衔接蛋白,与滤泡素相互作用蛋白-1 和 -2 (Fnip1、Fnip2) 以及主能量传感器 AMP 激酶 (AMPK) 结合。已知小鼠中 Bhd 基因的肾脏特异性缺失会导致多囊肾病 (PKD) 和肾细胞癌,而 Fnip1 在肾细胞发育和功能中的作用尚不清楚。在这项研究中,我们利用 Fnip1 基因组成型缺失的小鼠表明,Fnip1 的缺失足以导致肾囊肿形成,其特征为 AMPK 激活减少、mTOR 激活增加和代谢过度激活。通过 RNAseq,我们发现 Fnip1 破坏导致了许多以前与人 PKD 发展相关的细胞和分子变化,包括离子和氨基酸转运体表达的改变、细胞黏附增加和炎症增加。Fnip1 的缺失与 Tsc1 的缺失协同作用,过度激活 mTOR、增加 Erk 激活,并大大加速 PKD 的发展。我们的研究结果共同定义了 Fnip1 在调节肾脏发育和功能中的作用,并提供了一个模型,说明 Fnip1 的缺失如何导致 PKD 甚至肾细胞癌。