WRKY transcription factors form a large family of plant-specific transcription factors and participate in plant defense responses either as positive or negative regulators. In this study, we comprehensively analyzed the role of one of the group IIa WRKY transcription factors in rice, OsWRKY28, in the regulation of basal defense responses to a compatible race of the rice blast fungus Magnaporthe oryzae, strain Ina86-137. The expression analyses of the group IIa WRKY transcription factors in rice revealed that OsWRKY28, together with OsWRKY71, exhibit an early-induced expression prior to the late-induced expressions of OsWRKY62 and OsWRKY76. The GFP-OsWRKY28 fusion protein localized mainly in the nuclei of onion epidermal cells, and the maltose-binding protein-fused OsWRKY28 recombinant protein specifically bound to W-box elements. A transient reporter gene assay clearly showed that OsWRKY28 functions as a transcriptional repressor. Overexpression of OsWRKY28 in rice plants resulted in enhanced susceptibility to Ina86-137. Finally, transcriptome analysis revealed that the induction of several defense-related genes in the wild type after Ina86-137 infection was counteracted in OsWRKY28-overexpressing rice plants. These results strongly suggest that OsWRKY28 is a negative regulator of basal defense responses against Ina86-137 and acts as a modulator to maintain the responses at an appropriate level by attenuating the activation of defense-related gene expression levels.

The biological role of a secretory catalase of the rice blast fungus Magnaporthe oryzae was studied. The internal amino acid sequences of the partially purified catalase in the culture filtrate enabled us to identify its encoding gene as a catalase-peroxidase gene, CPXB, among four putative genes for catalase or catalase-peroxidase in M. oryzae. Knockout of the gene drastically reduced the level of catalase activity in the culture filtrate and supernatant of conidial suspension (SCS), and increased the sensitivity to exogenously added H₂O₂ compared with control strains, suggesting that CPXB is the major gene encoding the secretory catalase and confers resistance to H₂O₂ in hyphae. In the mutant, the rate of appressoria that induced accumulation of H₂O₂ in epidermal cells of the leaf sheath increased and infection at early stages was delayed; however, the formation of lesions in the leaf blade was not affected compared with the control strain. These phenotypes were complimented by reintroducing the putative coding regions of CPXB driven by a constitutive promoter. These results suggest that CPXB plays a role in fungal defense against H₂O₂ accumulated in epidermal cells of rice at the early stage of infection but not in pathogenicity of M. oryzae.

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Recently, discussions have considered how mental health and psychosocial support (MHPSS) can build upon local resilience in war-affected settings. To contribute to the knowledge in this field, the paper explored the gap between MHPSS and local communities in terms of perceived mental health problems and healing processes, and how the gap could be filled. Qualitative research was conducted in northern Rwanda with 43 participants between 2015 and 2016. Findings revealed how three particular gaps can isolate MHPSS recipients in their local community. First, whereas MHPSS applies bio-psychological frameworks to post-genocide mental health, community conceptualisations emphasise social aspects of suffering. Second, unlike MHPSS which encourages ‘talking’ about trauma, ‘practicing’ mutual support plays a major role in the community healing process. Third, MHPSS focuses on one part of the community (those who share the same background) and facilitates their healing in intervention groups. However, healing in natural communities continues in everyday life, through mutual support among different people. Despite these gaps, MHPSS recipients can be (re)integrated into the community through sharing suffering narratives and sharing life with other community members. The paper highlights the ways in which MHPSS could inclusively support different social groups in the overall geographical community, allowing members to preserve the existing reciprocity and recover collective life through their own initiatives.