Alternative transcription start site selection in Mr-OPY2 controls lifestyle transitions in the fungus Metarhizium robertsii

作者：Guo, Na; Qian, Ying; Zhang, Qiangqiang; Chen, Xiaoxuan; Zeng, Guohong; Zhang, Xing; Mi, Wubing; Xu, Chuan; Leger, Raymond J. St.; Fang, Weiguo^*

来源：Nature Communications, 2017, 8(1): 1565.

DOI：10.1038/s41467-017-01756-1

• OPEN READING FRAMES
• ENTOMOPATHOGENIC FUNGUS
• MESSENGER-RNA
• GENE-EXPRESSION
• MAP KINASE
• ANISOPLIAE
• PROTEIN
• VIRULENCE
• PATHOGENICITY
• TRANSLATION

Metarhizium robertsii is a versatile fungus with saprophytic, plant symbiotic and insect pathogenic lifestyle options. Here we show that M. robertsii mediates the saprophyte-to-insect pathogen transition through modulation of the expression of a membrane protein, Mr-OPY2. Abundant Mr-OPY2 protein initiates appressorium formation, a prerequisite for infection, whereas reduced production of Mr-OPY2 elicits saprophytic growth and conidiation. The precise regulation of Mr-OPY2 protein production is achieved via alternative transcription start sites. During saprophytic growth, a single long transcript is produced with small upstream open reading frames in its 5' untranslated region. Increased production of Mr-OPY2 protein on host cuticle is achieved by expression of a transcript variant lacking a small upstream open reading frame that would otherwise inhibit translation of Mr-OPY2. RNA-seq and qRT-PCR analyses show that Mr-OPY2 is a negative regulator of a transcription factor that we demonstrate is necessary for appressorial formation. These findings provide insights into the mechanisms regulating fungal lifestyle transitions.

• 出版日期2017-11-16
• 单位浙江大学