Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase
The NADPH-dependent HC-toxin reductase (HCTR), encoded by Hm1 in maize, inactivates HC-toxin produced by the fungus Cochliobolus carbonum, and thus confers resistance to the pathogen. The fact that C. carbonum only infects maize (Zea mays) and is the only species known to produce HC-toxin raises the...
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| Format: | Article |
| Language: | English |
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The American Phytopathological Society
1997-03-01
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| Series: | Molecular Plant-Microbe Interactions |
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| Online Access: | https://apsjournals.apsnet.org/doi/10.1094/MPMI.1997.10.2.234 |
| _version_ | 1811290183057801216 |
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| author | F. Han A. Kleinhofs A. Kilian S. E. Ullrich |
| author_facet | F. Han A. Kleinhofs A. Kilian S. E. Ullrich |
| author_sort | F. Han |
| collection | DOAJ |
| description | The NADPH-dependent HC-toxin reductase (HCTR), encoded by Hm1 in maize, inactivates HC-toxin produced by the fungus Cochliobolus carbonum, and thus confers resistance to the pathogen. The fact that C. carbonum only infects maize (Zea mays) and is the only species known to produce HC-toxin raises the question: What are the biological functions of HCTR in other plant species? An HCTR-like enzyme may function to detoxify toxins produced by pathogens which infect other plant species (R. B. Meeley, G. S. Johal, S. E. Briggs, and J. D. Walton, Plant Cell, 4:71–77, 1992). Hm1 homolog in rice (Y. Hihara, M. Umeda, C. Hara, Q. Liu, S. Aotsuka, K. Toriyama, and H. Uchimiya, unpublished) and HCTR activity in barley, wheat, oats and sorghum have been reported (R. B. Meeley and J. D. Walton, Plant Physiol. 97:1080–1086, 1993). To investigate the sequence conservation of Hm1 and HCTR in barley and the possible relationship of barley Hm1 homolog to the known disease resistance genes, we cloned and mapped a barley (Hordeum vulgare) Hm1-like gene. A putative full-length cDNA clone, Bhm1-18, was isolated from a cDNA library consisting of mRNA from young leaves, inflorescences, and immature embryos. This 1,297-bp clone encodes 363 amino acids which show great similarity (81.6%) with the amino acid sequence of HM1 in maize. Two loci were mapped to barley molecular marker linkage maps with Bhm1-18 as the probe; locus A (Bhm1A) on the long arm of chromosome 1, and locus B (Bhm1B) on the short arm of chromosome 1 which is syntenic to maize chromosome 9 containing the Hm2 locus. The Bhm1-18 probe hybridized strongly to a Southern blot of a wide range of grass species, indicating high conservation of HCTR at the DNA sequence level among grasses. The HCTR mRNA was detected in barley roots, leaves, inflorescences, and immature embryos. The conservation of the HCTR sequence, together with its expression in other plant species (R. B. Meeley and J. D. Walton, Plant Physiol. 97:1080–1086, 1993), suggests HCTR plays an important functional role in other plant species. |
| first_indexed | 2024-04-13T04:08:28Z |
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| publishDate | 1997-03-01 |
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| series | Molecular Plant-Microbe Interactions |
| spelling | doaj.art-0d5378ae432142088f1817cb41d08d102022-12-22T03:03:10ZengThe American Phytopathological SocietyMolecular Plant-Microbe Interactions0894-02821943-77061997-03-0110223423910.1094/MPMI.1997.10.2.234Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin ReductaseF. HanA. KleinhofsA. KilianS. E. UllrichThe NADPH-dependent HC-toxin reductase (HCTR), encoded by Hm1 in maize, inactivates HC-toxin produced by the fungus Cochliobolus carbonum, and thus confers resistance to the pathogen. The fact that C. carbonum only infects maize (Zea mays) and is the only species known to produce HC-toxin raises the question: What are the biological functions of HCTR in other plant species? An HCTR-like enzyme may function to detoxify toxins produced by pathogens which infect other plant species (R. B. Meeley, G. S. Johal, S. E. Briggs, and J. D. Walton, Plant Cell, 4:71–77, 1992). Hm1 homolog in rice (Y. Hihara, M. Umeda, C. Hara, Q. Liu, S. Aotsuka, K. Toriyama, and H. Uchimiya, unpublished) and HCTR activity in barley, wheat, oats and sorghum have been reported (R. B. Meeley and J. D. Walton, Plant Physiol. 97:1080–1086, 1993). To investigate the sequence conservation of Hm1 and HCTR in barley and the possible relationship of barley Hm1 homolog to the known disease resistance genes, we cloned and mapped a barley (Hordeum vulgare) Hm1-like gene. A putative full-length cDNA clone, Bhm1-18, was isolated from a cDNA library consisting of mRNA from young leaves, inflorescences, and immature embryos. This 1,297-bp clone encodes 363 amino acids which show great similarity (81.6%) with the amino acid sequence of HM1 in maize. Two loci were mapped to barley molecular marker linkage maps with Bhm1-18 as the probe; locus A (Bhm1A) on the long arm of chromosome 1, and locus B (Bhm1B) on the short arm of chromosome 1 which is syntenic to maize chromosome 9 containing the Hm2 locus. The Bhm1-18 probe hybridized strongly to a Southern blot of a wide range of grass species, indicating high conservation of HCTR at the DNA sequence level among grasses. The HCTR mRNA was detected in barley roots, leaves, inflorescences, and immature embryos. The conservation of the HCTR sequence, together with its expression in other plant species (R. B. Meeley and J. D. Walton, Plant Physiol. 97:1080–1086, 1993), suggests HCTR plays an important functional role in other plant species.https://apsjournals.apsnet.org/doi/10.1094/MPMI.1997.10.2.234dinucleotide-binding foldgenome syntenyHC-toxin synthetasephytotoxinspot blotch |
| spellingShingle | F. Han A. Kleinhofs A. Kilian S. E. Ullrich Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase Molecular Plant-Microbe Interactions dinucleotide-binding fold genome synteny HC-toxin synthetase phytotoxin spot blotch |
| title | Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase |
| title_full | Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase |
| title_fullStr | Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase |
| title_full_unstemmed | Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase |
| title_short | Cloning and Mapping of a Putative Barley NADPH-Dependent HC-Toxin Reductase |
| title_sort | cloning and mapping of a putative barley nadph dependent hc toxin reductase |
| topic | dinucleotide-binding fold genome synteny HC-toxin synthetase phytotoxin spot blotch |
| url | https://apsjournals.apsnet.org/doi/10.1094/MPMI.1997.10.2.234 |
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