Center for Lung Regenerative Medicine, Cincinnati Children's Research Foundation, Cincinnati, Ohio, USA.
Division of Pulmonary Biology, Cincinnati Children's Research Foundation, Cincinnati, Ohio, USA.
Sci Rep. 2017 Sep 6;7(1):10690. doi: 10.1038/s41598-017-11175-3.
FOXF1, a member of the forkhead box family of transcription factors, has been previously shown to be critical for lung development, homeostasis, and injury responses. However, the role of FOXF1 in lung regeneration is unknown. Herein, we performed partial pneumonectomy, a model of lung regeneration, in mice lacking one Foxf1 allele in endothelial cells (PDGFb-iCre/Foxf1 mice). Endothelial cell proliferation was significantly reduced in regenerating lungs from mice deficient for endothelial Foxf1. Decreased endothelial proliferation was associated with delayed lung regeneration as shown by reduced respiratory volume in Foxf1-deficient lungs. FACS-sorted endothelial cells isolated from regenerating PDGFb-iCre/Foxf1 and control lungs were used for RNAseq analysis to identify FOXF1 target genes. Foxf1 deficiency altered expression of numerous genes including those regulating extracellular matrix remodeling (Timp3, Adamts9) and cell cycle progression (Cdkn1a, Cdkn2b, Cenpj, Tubb4a), which are critical for lung regeneration. Deletion of Foxf1 increased Timp3 mRNA and protein, decreasing MMP14 activity in regenerating lungs. ChIPseq analysis for FOXF1 and histone methylation marks identified DNA regulatory regions within the Cd44, Cdkn1a, and Cdkn2b genes, indicating they are direct FOXF1 targets. Thus FOXF1 stimulates lung regeneration following partial pneumonectomy via direct transcriptional regulation of genes critical for extracellular matrix remodeling and cell cycle progression.
叉头框转录因子家族（forkhead box family of transcription factors）的成员 FOXF1 先前被证明对肺发育、内稳态和损伤反应至关重要。然而，FOXF1 在肺再生中的作用尚不清楚。在此，我们在血管内皮细胞中缺失一个 Foxf1 等位基因的小鼠（PDGFb-iCre/Foxf1 小鼠）中进行了部分肺切除术，这是一种肺再生模型。内皮细胞增殖在 Foxf1 缺陷的再生肺中显著减少。内皮细胞增殖减少与肺再生延迟有关，Foxf1 缺陷肺的呼吸量减少。从再生的 PDGFb-iCre/Foxf1 和对照肺中分离的 FACS 分选的内皮细胞用于 RNAseq 分析，以鉴定 FOXF1 的靶基因。Foxf1 缺陷改变了许多基因的表达，包括调节细胞外基质重塑（Timp3、Adamts9）和细胞周期进展（Cdkn1a、Cdkn2b、Cenpj、Tubb4a）的基因，这些基因对肺再生至关重要。Foxf1 的缺失增加了 Timp3 mRNA 和蛋白，减少了再生肺中 MMP14 的活性。FOXF1 和组蛋白甲基化标记的 ChIPseq 分析鉴定了 Cd44、Cdkn1a 和 Cdkn2b 基因内的 DNA 调控区域，表明它们是 FOXF1 的直接靶基因。因此，FOXF1 通过对细胞外基质重塑和细胞周期进展关键基因的直接转录调控，刺激部分肺切除术后的肺再生。
