By Ed Yong -
In Nicole King’s lab, a bacterium is making a group of tiny cells stick together. That might seem a little humdrum for a group whose members can build electric grids, create snow, and cripple nations. But King’s bacteria should not be overlooked, for they are recapping one of the most important events in the history of life: the move from one cell to many.
The cells in question are choanoflagellates– the closest living relatives of all animals. They’re not our direct ancestors, but they give us clues about what those ancestors were like when they were still swimming around as single cells. Choanoflagellates normally live in solitude, moving about with sperm-like tails and voraciously eating bacteria. But they can also form big colonies. If we can understand why this happens, we might get hints as to why our single-celled ancestors did the same.
King has now found the answer, and it’s a tantalising one. The solitary cells become sociable after being exposed a molecule called RIF-1 that’s produced by some of the bacteria that they eat. When they divide in two, the daughters normally go their separate ways; add a splash of RIF-1, and they stick together instead.
This article is about aneLifepaper in press: " Bacterial regulation of colony development in the closest living relatives of animals." Read about how the author's conference presentation inspired this piece and a story inScience-- months before publication in theeLifejournal -- in our blog.