Rohlfs Marko, Albert Martin, Keller Nancy P, Kempken Frank
Zoological Institute, Department of Animal Ecology, Christian-Albrechts-University of Kiel, Am Botanischen Garten 1-9, 24098 Kiel, Germany.
Biol Lett. 2007 Oct 22;3(5):523-5. doi: 10.1098/rsbl.2007.0338.
The vast repertoire of toxic fungal secondary metabolites has long been assumed to have an evolved protective role against fungivory. It still remains elusive, however, whether fungi contain these compounds as an anti-predator adaptation. We demonstrate that loss of secondary metabolites in the soil mould Aspergillus nidulans causes, under the attack of the fungivorous springtail Folsomia candida, a disadvantage to the fungus. Springtails exhibited a distinct preference for feeding on a mutant deleted for LaeA, a global regulator of Aspergillus secondary metabolites. Consumption of the mutant yielded a reproductive advantage to the arthropod but detrimental effects on fungal biomass compared with a wild-type fungus capable of producing the entire arsenal of secondary metabolites. Our results demonstrate that fungal secondary metabolites shape food choice behaviour, can affect population dynamics of fungivores, and suggest that fungivores may provide a selective force favouring secondary metabolites synthesis in fungi.
长期以来，人们一直认为大量有毒的真菌次生代谢产物具有进化而来的抵御食真菌作用的保护功能。然而，真菌是否将这些化合物作为一种反捕食者的适应性特征仍然难以捉摸。我们证明，在土壤霉菌构巢曲霉中，次生代谢产物的缺失在食真菌的跳虫白符跳的攻击下，会给真菌带来不利。跳虫对缺失LaeA（构巢曲霉次生代谢产物的全局调节因子）的突变体表现出明显的取食偏好。与能够产生全部次生代谢产物库的野生型真菌相比，食用该突变体对节肢动物产生了繁殖优势，但对真菌生物量产生了不利影响。我们的结果表明，真菌次生代谢产物塑造了食物选择行为，会影响食真菌动物的种群动态，并表明食真菌动物可能提供一种有利于真菌次生代谢产物合成的选择压力。
