A soil fungus and a marine alga have formed a beautiful friendship.
In a lab dish, scientists grew the fungus Mortierella elongata with a photosynthetic alga called Nannochloropsis oceanica. This odd couple formed a mutually beneficial team that kept each other going when nutrients such as carbon and nitrogen were scarce, researchers report July 16 in eLife.
Surprisingly, after about a month together, the partners got even cozier. Algal cells began growing inside the fungi’s super long cells called hyphae — the first time that scientists have identified a fungus that can harbor eukaryotic algae inside itself. (In eukaryotic cells, DNA is stored in the nucleus.) In lichens, a symbiotic pairing of fungi and algae, the algae remain outside of the fungal cells.