Confinement with Myosin-II suppression increases heritable loss of chromosomes, using live-cell ChReporters

Hayes, B.; Zhu, P.; Wang, M.; Pfeifer, C.; Xia, Y.; Phan, S.; Andrechak, J.; Du, J.; Tobin, M.; Anlas, A.; Dooling, L.; Irianto, J.; Lampson, M.; Discher, D.

doi:10.1101/2023.02.25.530049

bioRxiv · 10.1101/2023.02.25.530049

Confinement with Myosin-II suppression increases heritable loss of chromosomes, using live-cell ChReporters

Hayes, B.·Zhu, P.·Wang, M.·Pfeifer, C.·Xia, Y.·Phan, S.·Andrechak, J.·Du, J.·Tobin, M.·Anlas, A.·Dooling, L.·Irianto, J.·Lampson, M.·Discher, D.

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Abstract

Matrix around cells exerts many effects, some of which depend on the putative tumor suppressor Myosin-II, but whether such factors affect DNA sequences in a cell remains unclear. Here, live-cell monitoring of changes to chromosome copy numbers is developed and studied under diverse perturbations, including Myosin-II inhibition in confined mitosis. Squeezing of mitotic cells is seen in vivo and kills in vitro, but stem cells and cancer cells that survive show heritable loss of mono-allelic GFP/RFP-tagged constitutive genes that function as novel Chromosome-reporters (ChReporters). Myosin-II suppression increases such loss in 3D & 2D confinement but not in standard 2D, with "lethal" multipolar divisions proving myosin-dependent. Viable chromosome loss after confined mitosis associates more with mis-segregation than with multipolars or division number. Solid human tumors and teratomas in mice also show ChReporter loss and a confinement-signature of Myosin-II suppression, although losses are selected against in 2D culture. Heritable loss in rigid-confinement also appears independent of a spindle assembly checkpoint that functions in 2D. Confinement and myosin-II thus regulate pathways of heritable mechanogenetic change.

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Hayes, B., Zhu, P., Wang, M., Pfeifer, C., Xia, Y., Phan, S., Andrechak, J., Du, J., Tobin, M., Anlas, A., Dooling, L., Irianto, J., Lampson, M., Discher, D.. 2023-02-26. Confinement with Myosin-II suppression increases heritable loss of chromosomes, using live-cell ChReporters. https://doi.org/10.1101/2023.02.25.530049

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