title: The connection of protein O-mannosyltransferase family to the biocontrol potential of Beauveria bassiana, a fungal entomopathogen.
abstract: O-Mannosylation dependent on the protein O-mannosyltransferase (Pmt) family is an essential post-translational modification process in eukaryotes, but their connection to the biocontrol potential of a filamentous entomopathogen against arthropod pests is not understood. Here, we characterized the functions of three Pmt orthologues (Pmt1, Pmt2 and Pmt4) in the Pmt family of Beauveria bassiana and found that they were positive, but differential, regulators of the fungal growth, conidiation, multi-stress tolerance and virulence. Three Pmt2 knockdown mutants (ΔPmt2 was lethal), ΔPmt1 and ΔPmt4 grew 20-79% slower on nutrition-rich and limited media. Their conidial yields on a standard medium were reduced by 17-62%, accompanied with delayed germination. All the mutants became significantly less tolerant to most stresses of cell wall perturbation, high osmolarity, oxidation, wet heat and UV-B irradiation during colony growth and conidial germination and lost virulence by 53-62% via cuticle infection, although their virulence via hemocoel injection was not affected. Strikingly, these phenotypic defects were accompanied with remarkable cell wall damage, including thinner cell wall, lower conidial hydrophobicity and altered cell wall composition. All the changes were well restored to wild-type levels by targeted Pmt1 or Pmt4 complementation. Our results indicate for the first time that Pmt1, Pmt2 and Pmt4 are all required for the full biocontrol potential of B. bassiana despite differential contributions.
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China.
authors.forename: Juan-Juan
authors.initials: JJ
authors.lastname: Wang
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Qiu
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China.
authors.forename: Zhen-Jian
authors.initials: ZJ
authors.lastname: Chu
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China.
authors.forename: Sheng-Hua
authors.initials: SH
authors.lastname: Ying
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China mgfeng@zju.edu.cn.
authors.forename: Ming-Guang
authors.initials: MG
authors.lastname: Feng
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D052982:Beauveria / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D002473:Cell Wall / Q000187:drug effects / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D008364:Mannosyltransferases / Q000235:genetics / Q000378:metabolism*; D009036:Moths / Q000382:microbiology; D009154:Mutation; D016877:Oxidants / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013172:Spores, Fungal / Q000235:genetics / Q000254:growth & development; D014774:Virulence / Q000235:genetics
chemical_list: D000935:Antifungal Agents; D005656:Fungal Proteins; D016877:Oxidants; D012333:RNA, Messenger; D008364:Mannosyltransferases
keywords: asexual development; entomopathogenic fungi; multi-stress tolerance; protein O-mannosyltransferases; virulence