Open AccessHistidine kinases mediate differentiation, stress response, and pathogenicity in Magnaporthe oryzae
Author(s) -
Jacob Stefan,
Foster Andrew J.,
Yemelin Alexander,
Thines Eckhard
Publication year - 2014
Publication title -
microbiologyopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.881
H-Index - 36
ISSN - 2045-8827
DOI - 10.1002/mbo3.197
Subject(s) - biology , mutant , appressorium , histidine kinase , aspergillus oryzae , magnaporthe , gene , kinase , histidine , fungus , genetics , microbiology and biotechnology , botany , biochemistry , enzyme , magnaporthe grisea , oryza sativa , amino acid
The aim of this study is a functional characterization of 10 putative histidine kinases ( HIK s)‐encoding genes in the phytopathogenic fungus Magnaporthe oryzae . Two HIK s were found to be required for pathogenicity in the fungus. It was found that the mutant strains ΔMohik5 and ΔMohik8 show abnormal conidial morphology and furthermore ΔMohik5 is unable to form appressoria. Both HIK s MoHik5p and MoHik8p appear to be essential for pathogenicity since the mutants fail to infect rice plants. MoSln1p and MoHik1p were previously reported to be components of the HOG pathway in M. oryzae . The ΔMosln1 mutant is more susceptible to salt stress compared to ΔMohik1 , whereas ΔMohik1 appears to be stronger affected by osmotic or sugar stress. In contrast to yeast, the HOG signaling cascade in phytopathogenic fungi apparently comprises more elements. Furthermore, vegetative growth of the mutants ΔMohik5 and ΔMohik9 was found to be sensitive to hypoxia‐inducing Na NO 2 ‐treatment. Additionally, it was monitored that Na NO 2 ‐treatment resulted in MoHog1p phosphorylation. As a consequence we assume a first simplified model for hypoxia signaling in M. oryzae including the HOG pathway and the HIK s MoHik5p and MoHik9p.