Fig. 6: Premature separation of centromeres during meiosis in Atsororin mutant plants.

Fluorescence in situ hybridization experiment on male meiocytes with a probe directed against the centromeric regions (green) in wild-type plants and Atsororin, wapl1-1 wapl2 and Atsororin wapl1-1 wapl2 mutants. a Inactivation of AtSORORIN leads to premature loss of centromeric cohesion at the metaphase to anaphase transition during meiosis I. Inlays show magnifications of sister centromeric signals during metaphase I. Scale bar = 10 μm. b Magnifications of images depicting metaphase I stages for wild-type plans, Atsororin single mutants and Atsororin wapl1-1 wapl2 triple mutants. Premature splitting of centromeric signals is evident in the absence of AtSORORIN. Centromeres are stained in green and DNA is stained in magenta. Scale bar = 10 μm. c Quantification of the number of centromeric signals from metaphase I to prophase II stages in wild-type plants (n = 73) and Atsororin (n = 25), wapl1-1 wapl2 (n = 22) and Atsororin wapl1-1 wapl2 (n = 33) mutants. Fischer’s exact test was performed (*p < 0.05; ****p < 0.0001; ns—difference not significant). d Quantification of the number of centromeric signals at metaphase II in wild-type plants (n = 13) and Atsororin (n = 12), wapl1-1 wapl2 (n = 12) and Atsororin wapl1-1 wapl2 (n = 15) mutants. Fischer’s exact test was performed (****p < 0.0001; ns—difference not significant). e Quantification of the number of centromeric signals in tetrads (balanced: 4 nuclei with 5 centromere signals each) in wild type plants (n = 33) and Atsororin (n = 25), wapl1-1 wapl2 (n = 28) and Atsororin wapl1-1 wapl2 (n = 18) mutants. Two-sided Fischer’s exact test was performed (**p < 0.01; ****p < 0.0001; ns—difference not significant).