The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat
Gna1, a gene encoding a Gα subunit, a key component of signal transduction pathways, has been cloned and characterized in the wheat pathogen Stagonospora nodorum. Analysis of Gna1 expression during infection revealed a slight decrease in transcript levels shortly after germination, after which level...
| Main Authors: | , , , , |
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| Format: | Journal Article |
| Published: |
2004
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| Online Access: | http://hdl.handle.net/20.500.11937/2695 |
| _version_ | 1848744023717576704 |
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| author | Solomon, P. Tan, Kar-Chun Sanchez, P. Cooper, R. Oliver, Richard |
| author_facet | Solomon, P. Tan, Kar-Chun Sanchez, P. Cooper, R. Oliver, Richard |
| author_sort | Solomon, P. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Gna1, a gene encoding a Gα subunit, a key component of signal transduction pathways, has been cloned and characterized in the wheat pathogen Stagonospora nodorum. Analysis of Gna1 expression during infection revealed a slight decrease in transcript levels shortly after germination, after which levels steadily increased until sporulation. Inactivation of Gna1 had a pleiotropic effect on phenotype. The Gna1 mutants were less pathogenic, attributed to coinciding with a defect in direct penetration. Also, Gna1 mutants were unable to sporulate, showed an albino phenotype, and secreted one or more brown pigments into growth media. Analysis of growth medium identified tyrosine, phenylalanine, and dihydroxyphenylalanine (L-DOPA) were excreted by the gna1 strains but not by wild type. The presence of these compounds, and the insensitivity of melanization to tricyclazole suggest that S. nodorum synthesizes melanin via the L-DOPA pathway, the first fungal phytopathogen described to do so. Decreases in protease (and several other depolymerases) activities and sensitivity to osmotic stress were other phenotypes identified in the Gna1 mutants. Gna1 is the first signal transduction gene to be cloned and characterized from S. nodorum and its inactivation has uncovered several previously unknown facets of pathogenicity. |
| first_indexed | 2025-11-14T05:54:52Z |
| format | Journal Article |
| id | curtin-20.500.11937-2695 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T05:54:52Z |
| publishDate | 2004 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-26952017-09-13T16:01:42Z The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat Solomon, P. Tan, Kar-Chun Sanchez, P. Cooper, R. Oliver, Richard Gna1, a gene encoding a Gα subunit, a key component of signal transduction pathways, has been cloned and characterized in the wheat pathogen Stagonospora nodorum. Analysis of Gna1 expression during infection revealed a slight decrease in transcript levels shortly after germination, after which levels steadily increased until sporulation. Inactivation of Gna1 had a pleiotropic effect on phenotype. The Gna1 mutants were less pathogenic, attributed to coinciding with a defect in direct penetration. Also, Gna1 mutants were unable to sporulate, showed an albino phenotype, and secreted one or more brown pigments into growth media. Analysis of growth medium identified tyrosine, phenylalanine, and dihydroxyphenylalanine (L-DOPA) were excreted by the gna1 strains but not by wild type. The presence of these compounds, and the insensitivity of melanization to tricyclazole suggest that S. nodorum synthesizes melanin via the L-DOPA pathway, the first fungal phytopathogen described to do so. Decreases in protease (and several other depolymerases) activities and sensitivity to osmotic stress were other phenotypes identified in the Gna1 mutants. Gna1 is the first signal transduction gene to be cloned and characterized from S. nodorum and its inactivation has uncovered several previously unknown facets of pathogenicity. 2004 Journal Article http://hdl.handle.net/20.500.11937/2695 10.1094/MPMI.2004.17.5.456 restricted |
| spellingShingle | Solomon, P. Tan, Kar-Chun Sanchez, P. Cooper, R. Oliver, Richard The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat |
| title | The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat |
| title_full | The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat |
| title_fullStr | The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat |
| title_full_unstemmed | The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat |
| title_short | The Disruption of a Gα Subunit Sheds New Light on the Pathogenicity of Stagonospora nodorum on Wheat |
| title_sort | disruption of a gα subunit sheds new light on the pathogenicity of stagonospora nodorum on wheat |
| url | http://hdl.handle.net/20.500.11937/2695 |