The APSES transcription factor LmStuA is required for sporulation, pathogenic development and effector gene expression in Leptosphaeria maculans. (15th April 2015)

• Record Type: Journal Article
• Authors: Soyer, Jessica L.; Hamiot, Audrey; Ollivier, Bénédicte; Balesdent, Marie‐Hélène; Rouxel, Thierry; Fudal, Isabelle
• Is Part Of: Molecular plant pathology. Volume 16:Number 9(2015:Dec.)
• Page Start: 1000
• Page End: 1005
• Publication Date: 2015-04-15
• Subjects: Plant diseases -- Molecular aspects -- Periodicals; Plant-pathogen relationships -- Molecular aspects -- Periodicals; 571.936
• DOI: 10.1111/mpp.12249
• Languages: English
• ISSNs: 1464-6722

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p> <italic>Leptosphaeria maculans</italic> causes stem canker of oilseed rape (<italic>Brassica napus</italic>). The APSES transcription factor StuA is a key developmental regulator of fungi, involved in morphogenesis, conidia production and also more recently described as required for secondary metabolite production and for effector gene expression in phytopathogenic fungi. We investigated the involvement of the orthologue of <italic>StuA</italic> in <italic>L. maculans</italic>, <italic>LmStuA</italic>, in morphogenesis, pathogenicity and effector gene expression. <italic>LmStuA</italic> is induced during mycelial growth and at 14 days after infection, corresponding to the development of pycnidia on oilseed rape leaves, consistent with the function of StuA described so far. We set up the functional characterization of LmStuA using an RNA interference approach. Silenced <italic>LmStuA</italic> transformants showed typical phenotypic defects of <italic>StuA</italic> mutants with altered growth in axenic culture and impaired conidia production and perithecia formation. Silencing of <italic>LmStuA</italic> abolished the pathogenicity of <italic>L. maculans</italic> on oilseed rape leaves and also resulted in a drastic decrease in expression of at least three effector genes during <italic>in planta</italic> infection, suggesting either that <italic>LmStuA</italic> regulates, directly or indirectly, the expression of several effector genes in <italic>L. maculans</italic> or that the infection stage in which effectors are expressed is not reached when <italic>LmStuA</italic> expression is silenced.</p> </abstract>