Researchers in the Funabiki lab have devised a way to visualize molecules that are very rare, very small, or hard to produce naturally—including some viruses. The method, called MagIC cryo-EM, uses magnetic beads to hold molecules in place, keeping the sample intact and reducing sample loss by a thousandfold. “Because MagIC cryo-EM requires only a small number of particles compared to the conventional method, we can use it to visualize a broader variety of molecules, such as proteins that are very rare, or hard to produce and purify,” says first author Yasuhiro Arimura, a former research associate and currently a guest investigator in the Laboratory of Chromosome and Cell Biology, led by Hironori Funabiki. “It might be especially useful for the structural analysis of viruses and other infectious disease agents.” (fb)

Every living creature on Earth needs to protect itself from things that would do it harm. Bacteria are no different. And despite their relative simplicity, they deploy remarkably savvy defensive strategies against viral invaders. The most well-known is CRISPR-Cas9, adapted for human use as the first FDA-approved genetic editing technique. In the past year, researchers at Rockefeller’s Laboratory of Bacteriology, headed by Luciano Marraffini, and at the MSKCC’s Structural Biology Laboratory, headed by Dinshaw Patel, have been studying key immune components of some CRISPR systems called CARF effectors. These newly discovered weapons take different approaches to achieving the same goal: arresting cellular activity, which prevents a virus from spreading through the rest of the bacterial population. In a recent publication in Science, the scientists announce the newest CARF effector they’ve discovered, which they coined Cat1. Thanks to an unusually complex molecular structure, this protein can deplete a metabolite essential for cellular function. Left without fuel, the viral invader’s plans for a further onslaught are brought to a grinding halt. “The collective work of our labs is revealing just how effective—and different—these CARF effectors are,” says Marraffini. “The range of their molecular activities is quite amazing.” Learn more: https://bit.ly/4dvmBij (fb)