Fig. 1: The loss of Mastl induces chromosomal rearrangements and fragmentation.

Cartoon of the approach and timing used to synchronize cells in specific cell-cycle phases by double thymidine block before collecting mitosis-arrested cells by mitotic poisons EG5i (a) or Nocodazole [Noc]>>MG132 [MG] (b) via mitotic shake-off. c, f Representative images of Hoechst-stained Mastl^FLOX and Mastl^NULL iMEFs arrested in mitosis with (c) Eg5 inhibitor or with (f) Nocodazole>>MG132 (N = 3). Orange arrows indicate non-congressed fragments. d, g Percentage of cells from c and f with or without fragments, respectively. e, h Violin plots with box plot of the distribution of non-congressed fragments per cell from c and f, respectively. i Cartoon of the approach and timing used to synchronize cells by double thymidine block followed by a block in G2/M transition by RO-3306 CDK1 inhibitor before collecting mitosis-arrested cells by mitotic poisons colcemid via mitotic shake-off for chromosome spreads analyses. j Representative images of Giemsa-stained chromosomes spread from Mastl^FLOX and Mastl^NULL iMEFs. Orange arrows indicate chromosomal fragments (N = 2). Magnified images of fragments (k) and aberrant chromosomes from Mastl^NULL iMEFs (l–n). o Violin plot with embedded box plots and dot plots of the distribution of the number of chromosomes per cell from Mastl^FLOX and Mastl^NULL iMEFs with black and red dots depicting cells without or with chromosomal fragments, respectively. Representative images of immunofluorescence staining of Mastl^FLOX and Mastl^NULL iMEFs for p cells arrested in mitosis with Eg5i or r chromosomes spreads stained with DAPI, and stained with antibodies against the centromere (ACA) and the spindle (αTubulin) or phospho-Histone H3 on S10. q, s Magnified images of fragments from Mastl^NULL iMEFs from p and r, respectively. n: number of counted cells.