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Certain parasitic fungi fuse together their host’s cells in order to multiply, scientists reported today in Nature Microbiology.
Called microsporidia, these single-celled fungi can make people who are immunocompromised dangerously ill. Until now, little was known about how microsporidia spread and reproduce.
To find out, scientists infected the nematode worm Caenorhabditis elegans with microsporidia tagged with a red fluorescent dye. The team followed its progress as it multiplied and invaded all 20 of the animal’s gut cells, eventually fusing the organ into one giant, fungus-filled cell. The fungi were also able to fuse muscle cells.
“It’s like microsporidia have figured out that, like soldiers fighting in an urban warfare, it’s easier and safer to go from house to house by entering adjacent houses through a common wall, rather than by going through the front door of each house,” coauthor Emily Troemel of the University of California, San Diego said in a statement.