A classic in design in nature:
Chromosomes are densely packed DNA. The two “sister chromatids” of a chromosome, having been accurately duplicated during prophase and secured by centromeres, are arranged with all the other chromosomes on the spindle axis in metaphase. Soon after they are winched apart in anaphase into daughter cells. This elaborate choreography takes place every time a cell divides. The cell cycle is fascinating to anyone who has witnessed it under a light microscope, as you can see here:Evolution News, “DNA Packing: One of the Supreme Wonders of Nature” at Evolution News and Science Today (January 31, 2022)
Remarkable movies made with super-resolution atomic force microscopy show the parts of cohesin undergoing conformational changes. These hand-over-hand motions operate in the dark without eyes, using ATP for energy. They get it right every time!Evolution News, “DNA Packing: One of the Supreme Wonders of Nature” at Evolution News and Science Today (January 31, 2022)
The paper is open access.
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