title: Basic leucine zipper (bZIP) domain transcription factor MBZ1 regulates cell wall integrity, spore adherence, and virulence in Metarhizium robertsii.
abstract: Transcription factors (TFs) containing the basic leucine zipper (bZIP) domain are widely distributed in eukaryotes and display an array of distinct functions. In this study, a bZIP-type TF gene (MBZ1) was deleted and functionally characterized in the insect pathogenic fungus Metarhizium robertsii. The deletion mutant (ΔMBZ1) showed defects in cell wall integrity, adhesion to hydrophobic surfaces, and topical infection of insects. Relative to the WT, ΔMBZ1 was also impaired in growth and conidiogenesis. Examination of putative target gene expression indicated that the genes involved in chitin biosynthesis were differentially transcribed in ΔMBZ1 compared with the WT, which led to the accumulation of a higher level of chitin in mutant cell walls. MBZ1 exhibited negative regulation of subtilisin proteases, but positive control of an adhesin gene, which is consistent with the observation of effects on cell autolysis and a reduction in spore adherence to hydrophobic surfaces in ΔMBZ1. Promoter binding assays indicated that MBZ1 can bind to different target genes and suggested the possibility of heterodimer formation to increase the diversity of the MBZ1 regulatory network. The results of this study advance our understanding of the divergence of bZIP-type TFs at both intra- and interspecific levels.
authors: From the Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Wei
authors: W
authors: Huang
authors: From the Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Yanfang
authors: Y
authors: Shang
authors: From the Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Peilin
authors: P
authors: Chen
authors: From the Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Kai
authors: K
authors: Cen
authors: From the Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China cswang@sibs.ac.cn.
authors: Chengshu
authors: C
authors: Wang
mesh_terms: D000818:Animals; D001483:Base Sequence; D050976:Basic-Leucine Zipper Transcription Factors / Q000502:physiology*; D001665:Binding Sites; D012831:Bombyx / Q000382:microbiology; D002473:Cell Wall / Q000378:metabolism*; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins / Q000502:physiology*; D015870:Gene Expression; D015966:Gene Expression Regulation, Fungal; D057927:Hydrophobic and Hydrophilic Interactions; D007814:Larva / Q000382:microbiology; D052981:Metarhizium / Q000472:pathogenicity / Q000502:physiology*; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D013172:Spores, Fungal / Q000472:pathogenicity / Q000502:physiology*; D015533:Transcriptional Activation; D014774:Virulence
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D004271:DNA, Fungal; D005656:Fungal Proteins
keywords: Basic Leucine Zipper Domain; Cell Adherence; Cell Autolysis; Cell Wall; Cell Wall Integrity; Fungi; Insect; Metarhizium robertsii; Transcription Factor; Virulence Factor