Subunit Has Important Roles in Infection-Related Development and Stress Responses in .

The multifunctional carbon catabolite repression negative on TATA-box-less complex (CCR4-NOT) is a multi-subunit complex present in all eukaryotes, including fungi. This complex plays an essential role in gene expression; however, a functional study of the CCR4-NOT complex in the rice blast fungus has not been conducted. Seven genes encoding the putative CCR4-NOT complex were identified in the genome. Among these, a homologous gene, , was overexpressed during appressorium development in a previous study. Deletion of in resulted in a significant reduction in hyphal growth, conidiation, abnormal septation in conidia, conidial germination, and appressorium formation compared to the wild-type. Transcriptional analyses suggest that the gene affects conidiation and conidial morphology by regulating and in . Furthermore, exhibited a lack of pathogenicity, both with and without wounding, which is attributable to deficiencies in the development of invasive growth . This result was also observed in onion epidermal cells, which are non-host plants. In addition, the gene was involved in cell wall stress responses and heat shock. Taken together, these observations suggest that the gene is required for fungal infection-related cell development and stress responses in .