AGRO 39 |
| Two-component signal transduction pathway plays an important role for osmotic response in fungi. The mutations in os-1-like histidine kinase genes confer resistance to iprodione in several plant pathogens. In Neurospora crassa, the osmotic sensitive mutants including histidine kinase os-1, MAPKK kinase os-4, MAPK kinase os-5, and MAP kinase os-2 are resistant to iprodione and fludioxonil. Both fludioxonil and osmotic stress stimulated phosphorylation of OS-2 MAP kinase, expression of glycerol dehydrogenase gcy-1 gene, and its enzyme activity. In the os-1 mutant, OS-2 phosphorylation by fludioxonil was cancelled, but OS-2 was still activated in response to high osmotic stress. Other 9 histidine-kinase gene disruptants showed neither fungicide resistance nor osmotic sensitivity; however, the osmotic sensitivity of the os-1 mutant was partially suppressed by the hk3.79 disruption, but enhanced by the hksln and hk3.90 disruptions. These results suggest that several sensor histidine kinases cooperate with OS-1 to adapt to osmotic stress, in contrast, only OS-1 participates in fungicide sensitivity. |
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ACS International Award for Research in Agrochemicals: Symposium in Honor of Isamu Yamaguchi: Fungicides Sponsored by BASF Corporation
8:00 AM-11:45 AM, Monday, 11 September 2006 San Francisco Marriott -- Salon 1, Oral
Division of Agrochemicals |