Pulmonary surfactant synthesis in miRNA-26a-1/miRNA-26a-2 double knockout mice generated using the CRISPR/Cas9 system.
Pulmonary surfactant (PS), which is synthesized by type II alveolar epithelial cells (AECIIs), maintains alveolar integrity by reducing surface tension. Many premature neonates who lack adequate PS are predisposed to developing respiratory distress syndrome (RDS), one of the leading causes of neonatal morbidity and mortality. PS synthesis is influenced and regulated by various factors, including microRNAs. Previousin vitrostudies have shown that PS synthesis is regulated by miR-26a in fetal rat AECIIs. This study aimed to investigate the role of miR-26a in PS synthesisin vivo. To obtain a miR-26a-1/miR-26a-2 double knockout mouse model, we used the clustered regularly interspaced short palindromic repeat/CRISPR-associated protein 9 (CRISPR/Cas9) system, an important genome editing technology. Real-time PCR was performed to determine the miR-26a levels in various organs, as well as the mRNA levels of surfactant-associated proteins. Moreover, AECIIs and surfactant-associated proteins in lung tissues were analyzed by hematoxylin-eosin staining and immunohistochemistry. Homozygous offspring of miR-26a-1/miR-26a-2 double knockout mice generated using the CRISPR/Cas9 system were successfully obtained, and PS synthesis and the number of AECIIs were significantly increased in the miR-26a knockout mice. These results indicate that miR-26a plays an important role in PS synthesis in AECIIs.
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Ying-Hui
YH
Zhang
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Li-Zhi
LZ
Wu
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Hong-Lu
HL
Liang
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Yang
Y
Yang
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Jie
J
Qiu
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Qing
Q
Kan
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Wen
W
Zhu
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Cheng-Ling
CL
Ma
Department of Neonatology, Children's Hospital of Nanjing Medical University Nanjing 210008, Jiangsu, China.
Xiao-Yu
XY
Zhou
AECII; CRISPR/Cas9; PS; knockout mice; miR-26a