Figure 2
Derailed integrin traffic in β1-cytoplasmic tail mutant MEFs results in cytokinesis failure and induction of aneuploidy. (a) β1YYFF cells become binucleate on a β1-specific matrix. Representative still images of time-lapse analysis of β1YYFF_L0a and β1wt_L0a cells undergoing cytokinesis on a β1-integrin-specific matrix. Arrowheads indicate cells undergoing division and the resulting daughter cells. Numbers indicate minutes. (b) A schematic image of the experiment. β1wt and β1YYFF cells were plated on the β1-specific matrix component laminin to allow for one cell division. Subsequently, cells were allowed to grow to confluency in the presence of 10% FBS (allowing for β3-integrin-mediated adhesion) and this procedure was repeated four times after which all cell lines were continuously passaged under normal condition on plastic. (c) Chromosome numbers determined from metaphase spreads at the beginning and after four passages on β1 matrix (n=25–52 cells per group). Representative chromosome spreads are shown as insets with the number of chromosomes indicated. Arrows indicate mean chromosome number in each population. The P-values indicate the statistical difference in chromosome numbers of the cell lines before and after laminin treatment. (d) Karyotyping using multi-color fluorescence in situ hybridization (mFISH) of β1YYFF_L0a and β1YYFF_L4a shows structural and numerical aberrations in β1YYFF_L4a. 6 metaphases per cell line were analyzed.
