Affiliation:
1. Key Laboratory of Biotechnology and Crop Quality Improvement of Ministry of Agriculture of China, Biotechnology Research Center, Southwest University, Chongqing 400716, People's Republic of China
Abstract
ABSTRACT
Beauveria bassiana
is an economically important insect-pathogenic fungus which is widely used as a biocontrol agent to control a variety of insect pests. However, its insecticide efficacy in the field is often influenced by adverse environmental factors. Thus, understanding the genetic regulatory processes involved in the response to environmental stress would facilitate engineering and production of a more efficient biocontrol agent. Here, a mitogen-activated protein kinase (MAPK)-encoding gene, Bb
hog1
, was isolated from
B. bassiana
and shown to encode a functional homolog of yeast
HIGH-OSMOLARITY GLYCEROL 1
(
HOG1
). A Bb
hog1
null mutation was generated in
B. bassiana
by targeted gene replacement, and the resulting mutants were more sensitive to hyperosmotic stress, high temperature, and oxidative stress than the wild-type controls. These results demonstrate the conserved function of HOG1 MAPKs in the regulation of abiotic stress responses. Interestingly, ΔBb
hog1
mutants exhibited greatly reduced pathogenicity, most likely due to a decrease in spore viability, a reduced ability to attach to insect cuticle, and a reduction in appressorium formation. The transcript levels of two hydrophobin-encoding genes,
hyd1
and
hyd2
, were dramatically decreased in a ΔBb
hog1
mutant, suggesting that Bbhog1 may regulate the expression of the gene associated with hydrophobicity or adherence.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference58 articles.
1. Abbott, W. S. 1925. A method for computing the effectiveness of an insecticide. J. Econ. Entomol.18:265-267.
2. Altre, J. A., J. D. Vandenberg, and F. A. Cantone. 1999. Pathogenicity of Paecilomyces fumosoroseus isolates to diamondback moth, Plutella xylostella: correlation with spore size, germination speed, and attachment to cuticle. J. Invertebr. Pathol.73:332-338.
3. Bölker, M. 1998. Sex and crime: heterotrimeric G proteins in fungal mating and pathogenesis. Fungal Genet. Biol.25:143-156.
4. Boucias, D. G., and J. C. Pendland. 1991. Attachment of mycopathogens to cuticle, p. 101-127. In G. T. Cole and H. C. Hoch (ed.), The fungal spore and disease initiation in plants and animals. Plenum Press, New York, NY.
5. Nonspecific Factors Involved in Attachment of Entomopathogenic Deuteromycetes to Host Insect Cuticle
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