ABSTRACT
The mechanical environment generated through the adhesive interaction of endothelial cells (ECs) with the matrix controls nuclear tension, preventing aberrant gene synthesis and the transition from restrictive to leaky endothelium, a hallmark of acute lung injury (ALI). However, the mechanisms controlling tension transmission to the nucleus and EC-restrictive fate remain elusive. Here, we demonstrate that, in a kinase-independent manner, focal adhesion kinase (FAK) safeguards tension transmission to the nucleus to maintain EC-restrictive fate. In FAK-depleted ECs, robust activation of the RhoA-Rho-kinase pathway increased EC tension and phosphorylation of the nuclear envelope protein, emerin, activating DNMT3a. Activated DNMT3a methylates the KLF2 promoter, impairing the synthesis of KLF2 and its target S1PR1 to induce the leaky EC transcriptome. Repleting FAK (wild type or kinase dead) or inhibiting RhoA-emerin-DNMT3a activities in damaged lung ECs restored KLF2 transcription of the restrictive EC transcriptome. Thus, FAK sensing and control of tension transmission to the nucleus govern restrictive endothelium to maintain lung homeostasis.
Subject(s)
Cell Nucleus , Endothelial Cells , Kruppel-Like Transcription Factors , Transcriptome , rhoA GTP-Binding Protein , Animals , Humans , Mice , Cell Nucleus/metabolism , DNA Methyltransferase 3A , Endothelial Cells/metabolism , Focal Adhesion Kinase 1/metabolism , Focal Adhesion Kinase 1/genetics , Focal Adhesion Protein-Tyrosine Kinases/metabolism , Focal Adhesion Protein-Tyrosine Kinases/genetics , Human Umbilical Vein Endothelial Cells/metabolism , Kruppel-Like Transcription Factors/metabolism , Kruppel-Like Transcription Factors/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Phosphorylation , Promoter Regions, Genetic/genetics , rho-Associated Kinases/metabolism , rho-Associated Kinases/genetics , rhoA GTP-Binding Protein/metabolism , rhoA GTP-Binding Protein/genetics , Transcriptome/genetics , Male , FemaleABSTRACT
[Figure: see text].
