TY - JOUR
T1 - MiR-449a affects epithelial proliferation during the pseudoglandular and canalicular phases of avian and mammal lung development
AU - Sanford, Ethan L.
AU - Choy, Kwong W.
AU - Donahoe, Patricia K.
AU - Tracy, Adam A.
AU - Hila, Regis
AU - Loscertales, Maria
AU - Longoni, Mauro
N1 - Funding Information:
Funding was provided by National Institute of Child Health and Human Development P01 HD068250-03 to P.K.D. (www.nichd.nih.gov). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. We thank Meaghan K. Russell, Ph.D. and Drucilla J. Roberts, M.D. for logistical and technical support.
PY - 2016/2
Y1 - 2016/2
N2 - Congenital diaphragmatic hernia is associated with pulmonary hypoplasia and respiratory distress, which result in high mortality and morbidity. Although several transgenic mouse models of lung hypoplasia exist, the role of miRNAs in this phenotype is incompletely characterized. In this study, we assessed microRNA expression levels during the pseudoglandular to canalicular phase transition of normal human fetal lung development. At this critical time, when the distal respiratory portion of the airways begins to form, microarray analysis showed that the most significantly differentially expressed miRNA was miR-449a. Prediction algorithms determined that N-myc is a target of miR-449a and identified the likely miR 449a: N-myc binding sites, confirmed by luciferase assays and targeted mutagenesis. Functional ex vivo knock-down in organ cultures of murine embryonic lungs, as well as in ovo overexpression in avian embryonic lungs, suggested a role for miR-449a in distal epithelial proliferation. Finally, miR-449a expression was found to be abnormal in rare pulmonary specimens of human fetuses with Congenital Diaphragmatic Hernia in the pseudoglandular or canalicular phase. This study confirms the conserved role of miR-449a for proper pulmonary organogenesis, supporting the delicate balance between expansion of progenitor cells and their terminal differentiation, and proposes the potential involvement of this miRNA in human pulmonary hypoplasia.
AB - Congenital diaphragmatic hernia is associated with pulmonary hypoplasia and respiratory distress, which result in high mortality and morbidity. Although several transgenic mouse models of lung hypoplasia exist, the role of miRNAs in this phenotype is incompletely characterized. In this study, we assessed microRNA expression levels during the pseudoglandular to canalicular phase transition of normal human fetal lung development. At this critical time, when the distal respiratory portion of the airways begins to form, microarray analysis showed that the most significantly differentially expressed miRNA was miR-449a. Prediction algorithms determined that N-myc is a target of miR-449a and identified the likely miR 449a: N-myc binding sites, confirmed by luciferase assays and targeted mutagenesis. Functional ex vivo knock-down in organ cultures of murine embryonic lungs, as well as in ovo overexpression in avian embryonic lungs, suggested a role for miR-449a in distal epithelial proliferation. Finally, miR-449a expression was found to be abnormal in rare pulmonary specimens of human fetuses with Congenital Diaphragmatic Hernia in the pseudoglandular or canalicular phase. This study confirms the conserved role of miR-449a for proper pulmonary organogenesis, supporting the delicate balance between expansion of progenitor cells and their terminal differentiation, and proposes the potential involvement of this miRNA in human pulmonary hypoplasia.
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U2 - 10.1371/journal.pone.0149425
DO - 10.1371/journal.pone.0149425
M3 - Article
C2 - 26891231
AN - SCOPUS:84960539866
VL - 11
JO - PLoS One
JF - PLoS One
SN - 1932-6203
IS - 2
M1 - e0149425
ER -