Parental effects in a filamentous fungus: phenotype, fitness, and mechanism.

Often offspring rely on parental cues or resources to adjust their phenotype to current environmental conditions. Parental effects are those effects that the parental environment or phenotype can have on the offspring fitness. These effects may allow organisms to survive or adapt to challenging environments. Parental effects are well described in animals and plants but poorly studied in other organisms such as fungi. In this study we investigated parental effects in the fungus Neurospora crassa. We performed a match / mismatch experiment in which we measured colony size of strains that experienced either a matched or mismatched environment in their previous generation. We found a strong silver spoon effect in initial colony size, that lasted for one generation and increased fitness. We sequenced RNA-seq to explore the mechanism behind the parental effect and show that a radical transcription shift in spores is the main mechanisms behind this parental effect.