Friend or foe? Evolutionary history of glycoside hydrolase family 32 genes encoding for sucrolytic activity in fungi and its implications for plant-fungal symbioses

We found a strong signature of both ecological strategy and phylogeny on GH32 gene number in fungi. These data suggest that plant biotrophic fungi exhibit a wide range of ability to access plant-synthesized sucrose. Endophytic fungi are more similar to plant pathogens in their possession of GH32 genes, whereas most genomes of mycorrhizal taxa lack GH32 genes. Reliance on plant GH32 enzyme activity for C acquisition in these symbionts supports earlier predictions of possible plant control over C allocation in the mycorrhizal symbiosis.