Understanding more about how chromosomes segregate as a cell divides
Breaking a cell exactly in half requires huge feats of tiny engineering. Hundreds of proteins oversee the process of mitosis – but arguably the most crucial job, separating the precious DNA, still holds a few mysteries. Here scientists using super-resolution microscopy watch as microtubules – somewhere between fishing lines and microscopic scaffolding – (highlighted in green) first reach out from opposite sides of the cell towards the DNA (purple). The tubules meet in a criss-cross network seen from two different angles (top and bottom rows, left). Later in mitosis (middle and right) the tubules form thick bundles that bridge the gap between the different sides of the cell as the DNA lines up in the centre. Researchers believe kinetochores, linkers between DNA and microtubules, help to coordinate these overlap bundles,, which in turn guide the overall machinery as it begins the careful job of pulling the DNA apart.
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