Genetic analysis of the barley variegation mutant, grandpa1.a
Abstract Background Providing the photosynthesis factory for plants, chloroplasts are critical for crop biomass and economic yield. However, chloroplast development is a complicated process, coordinated by the cross-communication between the nucleus and plastids, and the underlying biogenesis mechan...
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| Format: | Article |
| Language: | English |
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BMC
2021-03-01
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| Series: | BMC Plant Biology |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s12870-021-02915-9 |
| _version_ | 1818870700430065664 |
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| author | Shengming Yang Megan Overlander Jason Fiedler |
| author_facet | Shengming Yang Megan Overlander Jason Fiedler |
| author_sort | Shengming Yang |
| collection | DOAJ |
| description | Abstract Background Providing the photosynthesis factory for plants, chloroplasts are critical for crop biomass and economic yield. However, chloroplast development is a complicated process, coordinated by the cross-communication between the nucleus and plastids, and the underlying biogenesis mechanism has not been fully revealed. Variegation mutants have provided ideal models to identify genes or factors involved in chloroplast development. Well-developed chloroplasts are present in the green tissue areas, while the white areas contain undifferentiated plastids that are deficient in chlorophyll. Unlike albino plants, variegation mutants survive to maturity and enable investigation into the signaling pathways underlying chloroplast biogenesis. The allelic variegated mutants in barley, grandpa 1 (gpa1), have long been identified but have not been genetically characterized. Results We characterized and genetically analyzed the grandpa1.a (gpa1.a) mutant. The chloroplast ultrastructure was evaluated using transmission electron microscopy (TEM), and it was confirmed that chloroplast biogenesis was disrupted in the white sections of gpa1.a. To determine the precise position of Gpa1, a high-resolution genetic map was constructed. Segregating individuals were genotyped with the barley 50 k iSelect SNP Array, and the linked SNPs were converted to PCR-based markers for genetic mapping. The Gpa1 gene was mapped to chromosome 2H within a gene cluster functionally related to photosynthesis or chloroplast differentiation. In the variegated gpa1.a mutant, we identified a large deletion in this gene cluster that eliminates a putative plastid terminal oxidase (PTOX). Conclusions Here we characterized and genetically mapped the gpa1.a mutation causing a variegation phenotype in barley. The PTOX-encoding gene in the delimited region is a promising candidate for Gpa1. Therefore, the present study provides a foundation for the cloning of Gpa1, which will elevate our understanding of the molecular mechanisms underlying chloroplast biogenesis, particularly in monocot plants. |
| first_indexed | 2024-12-19T12:11:11Z |
| format | Article |
| id | doaj.art-07829a7166414c8c835730ed819472f1 |
| institution | Directory Open Access Journal |
| issn | 1471-2229 |
| language | English |
| last_indexed | 2024-12-19T12:11:11Z |
| publishDate | 2021-03-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Plant Biology |
| spelling | doaj.art-07829a7166414c8c835730ed819472f12022-12-21T20:22:10ZengBMCBMC Plant Biology1471-22292021-03-0121111110.1186/s12870-021-02915-9Genetic analysis of the barley variegation mutant, grandpa1.aShengming Yang0Megan Overlander1Jason Fiedler2USDA-ARS Cereals Research Unit, Edward T. Schafer Agriculture Research CenterUSDA-ARS Cereals Research Unit, Edward T. Schafer Agriculture Research CenterUSDA-ARS Cereals Research Unit, Edward T. Schafer Agriculture Research CenterAbstract Background Providing the photosynthesis factory for plants, chloroplasts are critical for crop biomass and economic yield. However, chloroplast development is a complicated process, coordinated by the cross-communication between the nucleus and plastids, and the underlying biogenesis mechanism has not been fully revealed. Variegation mutants have provided ideal models to identify genes or factors involved in chloroplast development. Well-developed chloroplasts are present in the green tissue areas, while the white areas contain undifferentiated plastids that are deficient in chlorophyll. Unlike albino plants, variegation mutants survive to maturity and enable investigation into the signaling pathways underlying chloroplast biogenesis. The allelic variegated mutants in barley, grandpa 1 (gpa1), have long been identified but have not been genetically characterized. Results We characterized and genetically analyzed the grandpa1.a (gpa1.a) mutant. The chloroplast ultrastructure was evaluated using transmission electron microscopy (TEM), and it was confirmed that chloroplast biogenesis was disrupted in the white sections of gpa1.a. To determine the precise position of Gpa1, a high-resolution genetic map was constructed. Segregating individuals were genotyped with the barley 50 k iSelect SNP Array, and the linked SNPs were converted to PCR-based markers for genetic mapping. The Gpa1 gene was mapped to chromosome 2H within a gene cluster functionally related to photosynthesis or chloroplast differentiation. In the variegated gpa1.a mutant, we identified a large deletion in this gene cluster that eliminates a putative plastid terminal oxidase (PTOX). Conclusions Here we characterized and genetically mapped the gpa1.a mutation causing a variegation phenotype in barley. The PTOX-encoding gene in the delimited region is a promising candidate for Gpa1. Therefore, the present study provides a foundation for the cloning of Gpa1, which will elevate our understanding of the molecular mechanisms underlying chloroplast biogenesis, particularly in monocot plants.https://doi.org/10.1186/s12870-021-02915-9Gpa1Chloroplast biogenesisGenetic mappingBarley |
| spellingShingle | Shengming Yang Megan Overlander Jason Fiedler Genetic analysis of the barley variegation mutant, grandpa1.a BMC Plant Biology Gpa1 Chloroplast biogenesis Genetic mapping Barley |
| title | Genetic analysis of the barley variegation mutant, grandpa1.a |
| title_full | Genetic analysis of the barley variegation mutant, grandpa1.a |
| title_fullStr | Genetic analysis of the barley variegation mutant, grandpa1.a |
| title_full_unstemmed | Genetic analysis of the barley variegation mutant, grandpa1.a |
| title_short | Genetic analysis of the barley variegation mutant, grandpa1.a |
| title_sort | genetic analysis of the barley variegation mutant grandpa1 a |
| topic | Gpa1 Chloroplast biogenesis Genetic mapping Barley |
| url | https://doi.org/10.1186/s12870-021-02915-9 |
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