The inhibitor of apoptosis protein MoBir1 is involved in the suppression of hydrogen peroxide-induced fungal cell death, reactive oxygen species generation, and pathogenicity of rice blast fungus
The inhibitor of apoptosis protein (IAP) family has been identified in a variety of organisms. All IAPs contain one to three baculoviral IAP repeat (BIR) domains, which are required for anti-apoptotic activity. Here, we identified a type II BIR domain-containing protein, MoBir1, in the rice blast fungus Magnaporthe oryzae. Expression of the MoBIR1 gene in Saccharomyces cerevisiae suppressed hydrogen peroxide-induced cell death and delayed yeast cell chronological aging. Delayed aging was found to require the carboxyl terminus of MoBir1. M. oryzae transformants overexpressing the MoBIR1 gene demonstrated increased growth rate and biomass, delayed mycelial aging, and enhanced resistance to hydrogen peroxide but reduced reactive oxygen species generation and virulence. Moreover, MoBIR1-overexpressing transformants exhibited anti-apoptotic activity. However, MoBIR1 silencing resulted in no obvious phenotypic changes, compared with the wild-type M. oryzae strain Guy11. Our findings broaden the knowledge on fungal type II BIR domain-containing proteins.
KeywordsMagnaporthe oryzae Inhibitor of apoptosis Cell death ROS Pathogenicity
This study was funded by the National Key Research and Development Program of China (grant number 2016YFD0300700/2016YFD0300706), the Fundamental Research Funds for the Central Universities (grant number KYZ201816), and the Outstanding Youth Foundation of Jiangsu Province (grant number BK20160074).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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