When Dominique Bergmann learned that she and a lab she'd previously collaborated with were working on the same genetic pathway, her heart sank. “There was a moment of sheer, utter panic,” says Bergmann, a biologist at Stanford University in California. The pathway includes three genes involved in the development of stomata — pores in plants that take in carbon dioxide for photosynthesis and prevent excessive water loss.

Bergmann's group had collaborated with Keiko Torii, a biologist at the University of Washington in Seattle, and colleagues on a separate project, but didn't realize their research would steer them towards similar molecules. But in the end, says Bergmann, the two sets of results complemented each other.

Her team found two of the genes, SPEECHLESS (see page 537) and FAMA (reported in a previous paper), and Torii's group found the other, MUTE (see page 501). These are the first genes required for the development of stomatal cell lineages to be identified.

Similar molecules in animals, including humans, have a role in the differentiation of neural and muscle cells. Bergmann considers stomata to be among the “most influential cell types on the planet”. The next challenge, she says, will be deciphering how the three genes interact.