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bioRxiv · 10.1101/2021.08.09.455651

Blocking cell fusion inhibits age-induced polyploidy and maintains epithelial organization in Drosophila

Dehn, A. S.·Gogna, N.·Nishina, P. M.·Losick, V. P.
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Abstract

A characteristic of normal aging and age-related diseases is the remodeling of a tissues cellular organization through polyploid cell growth. Polyploidy arises from an increase in nuclear ploidy or the number of nuclei per cell. However, it is not known whether age-induced polyploidy is an adaption to stressors or a precursor to degeneration. Here, we find that the adult fruit flys abdominal epithelium becomes polyploid with age through generation of large multinucleated cells that make up more than 40% of the tissue area. The syncytia arise by cell fusion, not endomitosis. Epithelial multinucleation is also a characteristic of macular degeneration, including Ctnna1tvrm5, a mouse model for pattern dystrophy. Similarly, we find that the knockdown of alpha-catenin enhances multinucleation in the fly epithelium. We further show that age-induced polyploidy can be suppressed by inhibiting cell fusion revealing a means to maintain tissue organization in older animals.

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Dehn, A. S., Gogna, N., Nishina, P. M., Losick, V. P.. 2021-08-09. Blocking cell fusion inhibits age-induced polyploidy and maintains epithelial organization in Drosophila. https://doi.org/10.1101/2021.08.09.455651

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