In the past decade, scientists have watched protein and RNA molecules condensing into droplets, or membrane-free condensates, in many kinds of cells, from bacterial to human. They have also noted that the same proteins that form liquid droplets in healthy cells can “solidfy” in the context of disease, such as neurodegenerative disorders. But what makes certain molecules come together in the same droplet, while others are excluded, has been unexplained.
This week in Science, a team shows for the first time that RNA molecules recognize one another to condense into the same droplet due to specific 3D shapes that the molecules assume. The study’s senior author, Amy S. Gladfelter of University of North Carolina, Chapel Hill, began this work as part of the HHMI / HCIA Summer Institute at the MBL, a group of 70 scientists who explored this emerging paradigm of cellular organization over five summers of intense, synergistic research. Paper. (paywall) – Erin M. Langdon, Yupeng Qiu, Amirhossein Ghanbari Niaki, Grace A. McLaughlin, Chase Weidmann, Therese M. Gerbich, Jean A. Smith, John M. Crutchley, Christina M. Termini, Kevin M. Weeks, Sua Myong, Amy S. Gladfelter. MRNA structure determines specificity of a polyQ-driven phase separation. Science, 2018; eaar7432 DOI: 10.1126/science.aar7432 More.
See also: And now, the internet of cells