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Updated: Apr 5, 2026
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Point mutation impairs centromeric CENH3 loading and induces haploid plants
Raheleh Karimi-Ashtiyani1, Takayoshi Ishii1, Markus Niessen2
1Leibniz Institute of Plant Genetics and Crop Plant Research Gatersleben, 06466 Stadt Seeland, Germany;
Summary
A specific mutation in CENH3 (centromere-specific histone H3) reduces its loading at centromeres, impacting chromosome stability. This finding has potential applications in crop haploid technology.
Area of Science:
- Epigenetics and Chromosome Biology
- Plant Genetics and Breeding
Background:
- The centromere-specific histone H3 variant CENH3 (CENP-A) is crucial for kinetochore assembly and active centromere function.
- Errors in CENH3 processing can lead to centromere inactivation and chromosome instability.
Purpose of the Study:
- To investigate the effect of a single-point amino acid exchange in the centromere-targeting domain of CENH3.
- To assess the impact of this mutation on CENH3 loading and centromere function across different plant species.
Main Methods:
- Introduction of a specific point mutation (L130F) into the CENH3 gene.
- Complementation of cenh3-null mutant plants with the mutated CENH3 in Arabidopsis thaliana.
- Analysis of CENH3 loading and chromosome behavior in barley, sugar beet, and Arabidopsis thaliana.
Main Results:
- A single amino acid exchange in CENH3's centromere-targeting domain reduces CENH3 loading in barley, sugar beet, and Arabidopsis thaliana.
- In Arabidopsis thaliana, haploids were generated when mutated CENH3-complemented plants were crossed with wild-type.
- No uniparental chromosome elimination occurred when centromeres exclusively contained either mutated or wild-type CENH3.
Conclusions:
- The identified CENH3 mutation site is evolutionarily conserved, suggesting broad applicability.
- This research provides a foundation for developing novel haploid induction technologies in various crop species.
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