S-nitrosation impairs KLF4 activity and instigates endothelial dysfunction in pulmonary arterial hypertension
Yiqian Ban,
Yahan Liu,
Yazi Li,
Yuying Zhang,
Lei Xiao,
Yue Gu,
Shaoliang Chen,
Beilei Zhao,
Chang Chen,
Nanping Wang
Affiliations
Yiqian Ban
Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191, China; Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
Yahan Liu
Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191, China; Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
Yazi Li
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
Yuying Zhang
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
Lei Xiao
Cardiovascular Research Center, Xi’an Jiaotong University Health Science Center, Xi’an 710006, China
Yue Gu
Division of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210061, China
Shaoliang Chen
Division of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210061, China
Beilei Zhao
Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191, China; Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
Chang Chen
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Beijing Institute for Brain Disorders, Capital Medical University, Beijing 100069, China; Corresponding author at: National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
Nanping Wang
Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191, China; Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China; Advanced Institute for Medical Sciences, Dalian Medical University, Dalian 116044, China; Corresponding author at: Institute of Cardiovascular Science, Peking University Health Science Center, Beijing 100191, China.
Krüppel-like factor 4 (KLF4) is a transcription factor with conserved zinc finger domains. As an essential regulator of vascular homeostasis, KLF4 exerts a protective effect in endothelial cells (ECs), including regulating vasodilation, inflammation, coagulation and oxidative stress. However, the underlying mechanisms modifying KLF4 activity in mediating vascular function remain poorly understood. Recently, essential roles for S-nitrosation have been implicated in many pathophysiologic processes of cardiovascular disease. Here, we demonstrated that KLF4 could undergo S-nitrosation in response to nitrosative stress in ECs, leading to the decreased nuclear localization with compromised transactivity. Mass-spectrometry and site-directed mutagenesis revealed that S-nitrosation modified KLF4 predominantly at Cys437. Functionally, KLF4 dependent vasodilatory response was impaired after S-nitrosoglutathione (GSNO) treatment. In ECs, endothelin-1 (ET-1) induced KLF4 S-nitrosation, which was inhibited by an endothelin receptor antagonist Bosentan. In hypoxia-induced rat model of pulmonary arterial hypertension (PAH), S-nitrosated KLF4 (SNO-KLF4) was significantly increased in lung tissues, along with decreased nuclear localization of KLF4. In summary, we demonstrated that S-nitrosation is a novel mechanism for the post-translational modification of KLF4 in ECs. Moreover, these findings suggested that KLF4 S-nitrosation may be implicated in the pathogenesis of vascular dysfunction and diseases such as PAH. Keywords: Krüppel-like factor 4, S-nitrosation, Endothelium, Pulmonary arterial hypertension