Some moulds boost their genetic diversity by pumping DNA through sprawling networks of fungal fibres.

Credit: PATRICK HICKEY/UCLA

Unlike plants and animals, certain fungi form colonies of interconnected cells with mobile, genetically distinct nuclei in a common cytoplasm. Marcus Roper at the University of California, Los Angeles, and his colleagues tagged nuclei of the red bread mould Neurospora crassa with either green or red fluorescent proteins (pictured) and then monitored how the nuclei moved through fungal filaments, which branch and fuse into a hyphal network. The team found that fluids push nuclei through the tiny tubes at a rate of 3 millimetres per hour, supplying the tips of the network with a diverse mix of DNA. The network's structure enhances hydraulic flow, boosts nuclear mixing and could help fungi to recombine genes to create more robust mould, the authors say.

Proc. Natl Acad. Sci. USA http://dx.doi.org/10.1073/pnas.1220842110 (2013)