TOP1 — Fusarium graminearum PH-1

Summary

FgTOP1 (FGRAMPH1_01G23385) on chromosome 4 of Fusarium graminearum PH-1 encodes a type I topoisomerase, a DNA-binding enzyme with DNA breakage. It is associated with DNA topological change, regulation of mitotic recombination, mitotic chromosome condensation, DNA replication elongation, rRNA transcription, asexual sporulation, hyphal growth, and nuclear movement. The protein localises to the nucleus, nucleolus, chromatin, and mitochondria. Phenotypic associations include delayed cell cycle progression in anaphase, increased sporulation, increased thermotolerance, decreased chemical resistance, abnormal filamentous growth, and altered mitotic recombination rates. Studies of related topoisomerase I family members in other species link the family to reduced virulence, delayed vegetative growth, and increased gamma ray resistance.