Research Article

Current Genetics

, 55:449

First online:

Gibberella zeae chitin synthase genes, GzCHS5 and GzCHS7, are required for hyphal growth, perithecia formation, and pathogenicity

  • Jung-Eun KimAffiliated withDepartment of Agricultural Biotechnology, Centers for Fungal Pathogenesis and for Agricultural Biomaterials, Seoul National University
  • , Hyo-Jin LeeAffiliated withDepartment of Agricultural Biotechnology, Centers for Fungal Pathogenesis and for Agricultural Biomaterials, Seoul National University
  • , Jungkwan LeeAffiliated withDepartment of Agricultural Biotechnology, Centers for Fungal Pathogenesis and for Agricultural Biomaterials, Seoul National University
  • , Ki Woo KimAffiliated withNational Instrumentation Center for Environmental Management, Seoul National University
  • , Sung-Hwan YunAffiliated withDepartment of Medical Biotechnology, Soonchunhyang University
  • , Won-Bo ShimAffiliated withDepartment of Plant Pathology and Microbiology, Texas A&M University
  • , Yin-Won LeeAffiliated withDepartment of Agricultural Biotechnology, Centers for Fungal Pathogenesis and for Agricultural Biomaterials, Seoul National University Email author 

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Gibberella zeae causes Fusarium head blight of cereal crops, and sexual spores of the fungus play an important role as primary inocula. We isolated a restriction enzyme-mediated integration (REMI) transformant, ZH431, of G. zeae with defects in perithecia formation and virulence. Integration of the REMI vector resulted in disruption of GzCHS7 gene, which encodes a putative class VII chitin synthase with high similarity to Fusarium oxysporum ChsVb. A second chitin synthase, GzCHS5, is adjacently located in a head-to-head configuration with GzCHS7, and its deduced protein sequence showed similarity with a class V chitin synthase in F. oxysporum. Neither ΔGzChs5 nor ΔGzChs7 mutants produced perithecia or caused disease on barley heads. Microscopic observation revealed that both mutants formed balloon-shaped hyphae and intrahyphal hyphae and that cell wall rigidity of the mutants was weaker than that of the wild-type strain. Transcription profiles of GzCHS5 and GzCHS7 were not altered in ΔGzChs7 and ΔGzChs5, respectively, suggesting that transcription regulations of the genes are independent of each other. Our results demonstrate that GzCHS5 and GzCHS7 are indispensable for perithecia formation and pathogenicity as well as normal septa formation and hyphal growth in G. zeae.

Keywords

Balloon-shaped hyphae Cell wall rigidity Fusarium graminearum Intrahyphal hyphae Septa formation