Homeobox Transcription Factors Are Required for Fungal Development and the Suppression of Host Defense Mechanisms in the -Pepper Pathosystem.

, an ascomycete phytopathogenic fungus, is the main causal agent of serious yield losses of economic crops worldwide. The fungus causes anthracnose disease on several fruits, including peppers. However, little is known regarding the underlying molecular mechanisms involved in the development of anthracnose caused by this fungus. In an initial step toward understanding the development of anthracnose on pepper fruits, we retrieved 624 transcription factors (TFs) from the whole genome of . and comparatively analyzed the entire repertoire of TFs among phytopathogenic fungi. Evolution and proliferation of members of the homeobox-like superfamily, including homeobox (HOX) TFs that regulate the development of eukaryotic organisms, were demonstrated in the genus . . was found to contain 10 HOX TF genes ( to ), which were functionally characterized using deletion mutants of each gene. Notably, was identified as a pathogenicity factor required for the suppression of host defense mechanisms, which represents a new role for HOX TFs in pathogenic fungi. and were found to play essential roles in conidiation and appressorium development, respectively, in a stage-specific manner in . . Our study provides a molecular basis for understanding the mechanisms associated with the development of anthracnose on fruits caused by . , which will aid in the development of novel approaches for disease management. The ascomycete phytopathogenic fungus, , causes serious yield loss on peppers. However, little is known about molecular mechanisms involved in the development of anthracnose caused by this fungus. We analyzed whole-genome sequences of and isolated 624 putative TFs, revealing the existence of 10 homeobox (HOX) transcription factor (TF) genes. We found that is a pathogenicity factor required for the suppression of host defense mechanism, which represents a new role for HOX TFs in pathogenic fungi. We also found that and play essential roles in conidiation and appressorium development, respectively, in a stage-specific manner in . Our study contributes to understanding the mechanisms associated with the development of anthracnose on fruits caused by . , which will aid for initiating novel approaches for disease management.