Figure 3
From: Mutation of NIMA-related kinase 1 (NEK1) leads to chromosome instability
Aneuploidy in NEK1 -/- cells. (A, B). Passage 4 RTEs cultured from NEK1 -/- mice and from wild type littermates were treated with colchicine and hypotonically lysed. Free chromosomes were dispersed and stained with Giemsa. A. Representative images of chromosome spreads. Note the more variable sister chromatids observed in the spread prepared from NEK1 -/- cells. Bar = 50 μM. B. Numbers of chromosomes per cell were quantified (more than 200 spreads from at least two unique cell lines for each genotype). (C, D) Wild type or NEK1 -/- RTEs at passage 4 were harvested during exponential phase growth, stained with propidium iodide, and quantified by FACS for DNA content. C. Plots for wild type cells show sharp 2n and 4n peaks. One NEK1 -/- line (#432) shows a substantial fraction of cells with >4n DNA content (yellow). In another NEK1 -/- line (#436), the majority of the cells have >2n DNA content, and a broad peak is seen, representing a range of different DNA content in individual cells. D. Histograms showing 5-13% of cells with >4n DNA content and 6-9% with DNA content intermediate between 2n and 4n, specifically in NEK1 -/- RTEs.