miR-19c Regulates Lymphatic Vessel Development Through Tgfβ1a

• Main Authors: Tony Lin, 林偉德
• Other Authors: Jeff Lee
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/s6798v

碩士 === 國立臺灣大學 === 生命科學系 === 104 === MicroRNAs (miRNA) are known regulators of gene expression in different cellular processes including development. Recently, different miRNAs were found to be enriched in endothelial cells (ECs) that suggests a role of miRNA in vascular development. miRNAs have been shown to mediate blood vessel development. However, their role in lymphatic vessel development is less well understood. Using zebrafish as a model, we analyzed miRNAs in ECs and found one miRNA, miR-19c, with increased expression between 24 to 48 hours post fertilization (hpf). We show that knocking down miR-19c by morpholino oligonucleotides has no effect on blood or lymphatic vasculature, while over expression by injecting miRNA mimic causes over-branching of lymphatic vessels. This suggests miR-19c as a positive regulator of lymphatic development. One probable target of miR-19c is transforming growth factor β 1a (tgfβ1a). Tgfβ1a may have the potential to prevent lymphangiogenesis and promote angiogenesis. Thus, we co-injected miR-19c mimic with tgfβ1a and they lessened the lymphatic defects observed. Moreover, we validated that tgfβ1a is a direct target of miR19c by Luciferase assay. Taken together, these results demonstrate that miR-19c is a positive gene regulator of lymphatic development and targets tgfβ1a to reduce anti-lymphatic signals during development.