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bioRxiv · 10.1101/532325

Yorkie controls tube length and apical barrier integrity in the developing Drosophila airways

Papadopoulos, D. K.·Tomancak, P.·Tsarouhas, V.·Samakovlis, C.·Knust, E.·Skouloudaki, K.
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Abstract

Epithelial organ size and shape depend on cell shape changes, cell-matrix communication and apical membrane growth. The Drosophila embryonic tracheal network is an excellent model to study these processes. Here, we show that the transcriptional co-activator of the Hippo pathway, Yorkie (YAP in vertebrates), plays distinct roles in the developing Drosophila airways. Yorkie exerts a cytoplasmic function by binding Drosophila Twinstar, the orthologue of the vertebrate actin-severing protein Cofilin, to regulate F-actin levels and apical cell membrane size, which are required for proper tracheal tube elongation. Second, Yorkie controls water-tightness of tracheal tubes by transcriptional regulation of the enzyme{delta} -aminolevulinate synthase (Alas). We conclude that Yorkie has a dual role in tracheal development to ensure proper tracheal growth and functionality. Short SummaryThis work identified an alternative role of the transcriptional co-activator Yorkie (Yki) in controlling water impermeability and tube size of the developing Drosophila airways. Tracheal impermeability is triggered by Yki-mediated transcriptional regulation of{delta} -aminolevulinate synthase, Alas, whereas tube elongation is controlled by binding of Yki to the actin severing factor Twinstar.

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Papadopoulos, D. K., Tomancak, P., Tsarouhas, V., Samakovlis, C., Knust, E., Skouloudaki, K.. 2019-01-28. Yorkie controls tube length and apical barrier integrity in the developing Drosophila airways. https://doi.org/10.1101/532325

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