Publicação
Decoding the interplay between TAZ and metabolism in early lung development
| Resumo: | Lung branching morphogenesis results from the crosstalk between epithelial and mesenchymal compartments and it is mainly regulated by multiple signaling pathways, namely Hippo signaling pathway. Hippo signaling pathway is a highly conserved kinase cascade that plays important roles in organ size control, repair and homeostasis. YAP and TAZ are the major transducers of Hippo pathway. The phosphorylation status of YAP/TAZ complex determines its subcellular localization and, consequently, the activation of the pathway. For instance, the non-phosphorylated YAP/TAZ is present in the nucleus where it associates with transcription factors like the TEAD family or RUNX2 promoting the transcription of target genes linked to cell proliferation and apoptosis. Several studies have described, over the years, the impact of metabolic pathways on Hippo regulation and activity. However, lung metabolic profile and the impact of Hippo modulation on the embryonic lung metabolic signature are still largely unknown. Therefore, this project aimed to study the impact of TAZ modulation on the chick lung metabolic profile. For this purpose, in vitro lung explants were treated with an inducer of TAZ nuclear localization (TM- 25659). Cultured lungs were morphometrically analyzed and processed for Western blot analysis, in situ hybridization and qRT-PCR. Moreover, culture medium was collected and analyzed by 1H-NMR spectroscopy. Lung explants stimulated with the TAZ inducer displayed an increase of 12% in branching, in a dose-dependent manner, when compared to controls. As expected, TAZ manipulation did not affect total YAP and TAZ protein expression levels but it promoted a mild increase in runx2 expression levels. qRT-PCR analysis revealed an increase of glut8, mct8, pdh and ldh expression levels when compared to controls. 1H-NMR spectroscopy revealed an increase in the secretion of succinate and acetate to the extracellular medium after explant stimulation with a TAZ inducer. Finally, embryonic lung metabolite profile was determined, and high lactate tissue levels were detected. TAZ manipulation had a mild impact in lung branching nonetheless it induced alterations in the expression levels of different enzymes and transporters of glucose catabolism. Furthermore, alterations in the amount of certain key metabolites was also noticed in TAZ-induced explants. Taken together, these results highlight a potential role for TAZ in the regulation of embryonic lung metabolic profile. This is the first study showing the contribution of Hippo signaling to metabolic reprograming of early lung development through the modulation of glucose catabolism-related genes. These findings may contribute to uncover new therapeutic targets to treat lung developmental disorders. |
|---|---|
| Autores principais: | Silva, Henrique Emanuel Araújo |
| Assunto: | Development Hippo Lung Metabolism TAZ Desenvolvimento Metabolismo Pulmão |
| Ano: | 2019 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade do Minho |
| Idioma: | inglês |
| Origem: | RepositóriUM - Universidade do Minho |
| Resumo: | Lung branching morphogenesis results from the crosstalk between epithelial and mesenchymal compartments and it is mainly regulated by multiple signaling pathways, namely Hippo signaling pathway. Hippo signaling pathway is a highly conserved kinase cascade that plays important roles in organ size control, repair and homeostasis. YAP and TAZ are the major transducers of Hippo pathway. The phosphorylation status of YAP/TAZ complex determines its subcellular localization and, consequently, the activation of the pathway. For instance, the non-phosphorylated YAP/TAZ is present in the nucleus where it associates with transcription factors like the TEAD family or RUNX2 promoting the transcription of target genes linked to cell proliferation and apoptosis. Several studies have described, over the years, the impact of metabolic pathways on Hippo regulation and activity. However, lung metabolic profile and the impact of Hippo modulation on the embryonic lung metabolic signature are still largely unknown. Therefore, this project aimed to study the impact of TAZ modulation on the chick lung metabolic profile. For this purpose, in vitro lung explants were treated with an inducer of TAZ nuclear localization (TM- 25659). Cultured lungs were morphometrically analyzed and processed for Western blot analysis, in situ hybridization and qRT-PCR. Moreover, culture medium was collected and analyzed by 1H-NMR spectroscopy. Lung explants stimulated with the TAZ inducer displayed an increase of 12% in branching, in a dose-dependent manner, when compared to controls. As expected, TAZ manipulation did not affect total YAP and TAZ protein expression levels but it promoted a mild increase in runx2 expression levels. qRT-PCR analysis revealed an increase of glut8, mct8, pdh and ldh expression levels when compared to controls. 1H-NMR spectroscopy revealed an increase in the secretion of succinate and acetate to the extracellular medium after explant stimulation with a TAZ inducer. Finally, embryonic lung metabolite profile was determined, and high lactate tissue levels were detected. TAZ manipulation had a mild impact in lung branching nonetheless it induced alterations in the expression levels of different enzymes and transporters of glucose catabolism. Furthermore, alterations in the amount of certain key metabolites was also noticed in TAZ-induced explants. Taken together, these results highlight a potential role for TAZ in the regulation of embryonic lung metabolic profile. This is the first study showing the contribution of Hippo signaling to metabolic reprograming of early lung development through the modulation of glucose catabolism-related genes. These findings may contribute to uncover new therapeutic targets to treat lung developmental disorders. |
|---|