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bioRxiv · 10.1101/2020.10.25.354431

Non-apoptotic enteroblast-specific role of the initiator caspase Dronc for development and homeostasis of the Drosophila intestine

Lindblad, J. L.·Tare, M.·Amcheslavsky, A.·Shields, A.·Bergmann, A.
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Abstract

The initiator caspase Dronc is the only CARD-domain containing caspase in Drosophila and is essential for apoptosis. Here, we report that homozygous dronc mutant adult animals are short-lived due to the presence of a poorly developed, defective and leaky intestine. Interestingly, this mutant phenotype can be significantly rescued by enteroblast-specific expression of dronc+ in dronc mutant animals, suggesting that proper Drone function specifically in enteroblasts, one of four cell types in the intestine, is critical for normal development of the intestine. Furthermore, enteroblast-specific knockdown of dronc in adult intestines triggers hyperplasia and differentiation defects. These enteroblast-specific functions of Drone do not require the apoptotic pathway and thus occur in a non-apoptotic manner. In summary, we demonstrate that an apoptotic initiator caspase has a very critical non-apoptotic function for normal development and for the control of the cell lineage in the adult midgut and therefore for proper physiology and homeostasis. HighlightsO_LIdronc mutants die from a fragile and leaky intestine C_LIO_LIdronc has a critical function in enteroblasts of the intestine C_LIO_LIdronc controls proliferation and differentiation in the intestine C_LIO_LIdronc performs these functions in an apoptosis-independent (non-apoptotic) manner C_LI

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Lindblad, J. L., Tare, M., Amcheslavsky, A., Shields, A., Bergmann, A.. 2020-10-26. Non-apoptotic enteroblast-specific role of the initiator caspase Dronc for development and homeostasis of the Drosophila intestine. https://doi.org/10.1101/2020.10.25.354431

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