Biological function of a homeobox transcription factor CsHtf1 in Colletotrichum siamense

Abstract:

[Background] Colletotrichum siamense was the main pathogen of rubber anthracnose, which seriously restricted the yield of natural rubber. Homeobox transcription factors were widely found in plant-pathogenic fungi and involved in asexual reproduction, infection, and metabolism of fungi. [Objective] To determine the biological function of a homeobox transcription factor CsHtf1 identified in Colletotrichum siamense. [Methods] The gene-knockout mutant of Cshtf1 was obtained by homologous recombination, and its phenotypes such as vegetative growth, conidial production, and pathogenicity were analyzed. [Results] The Cshtf1 gene encoded 600 amino acids and contained a HOX domain. Compared with the wild type, the Cshtf1 knockout mutant showed no significant difference in vegetative growth and pathogenicity, whereas the conidial production of the mutant was significantly reduced, and the production of melanin increased. [Conclusion] CsHtf1 was involved in the regulation of conidiation and melanin production in Colletotrichum siamense.