In this week's Science, scientists from the Salk Institute and the University of California, San Diego, report a new imaging technique that enabled them to visualize the 3D structure of chromatin and gain new insights into how it is packed into the nucleus of human cells. Dubbed ChromEMT, the method makes use of a fluorescent dye that stains DNA and selectively enhances its contrast in electron microscopy. Using the approach, the researchers were able to view the ultrastructure and 3D organization of individual chromatin polymers, megabase domains, and mitotic chromosomes. They show that chromatin is a disordered 5- to 24-nanometer diameter curvilinear chain that is packed at different 3D concentrations depending on whether cells are in mitosis and interphase. GenomeWeb has more on this here.
And in Science Advances, a team of Japanese investigators reports the first successful transformation of chrysanthemums' color from their natural red or pink to true blue. To do so, the researchers expressed in the flowers two genes from butterfly peas and Canterbury bells that are known to be linked to blue coloration. The result was a shift in most of the modified chrysanthemums color to a hue in the blue or violet-blue color groups — a development that may lead to the production of other blue flowers. The Scan also covers this here.