New breeding technologies accelerate germplasm improvement and reduce the cost of goods in seed production1,2,3. Many such technologies could use in vivo paternal haploid induction (HI), which occurs when double fertilization precedes maternal (egg cell) genome loss. Engineering of the essential CENTROMERIC HISTONE (CENH3) gene induces paternal HI in Arabidopsis4,5,6. Despite conservation of CENH3 function across crops, CENH3-based HI has not been successful outside of the Arabidopsis model system7. Here we report a commercially operable paternal HI line in wheat with a ~7% HI rate, identified by screening genome-edited TaCENH3α-heteroallelic combinations. Unlike in Arabidopsis, edited alleles exhibited reduced transmission in female gametophytes, and heterozygous genotypes triggered higher HI rates than homozygous combinations. These developments might pave the way for the deployment of CENH3 HI technology in diverse crops.
The authors declare that all data supporting the findings of this study are available in the manuscript and the Supplementary Materials.
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We thank Z. Chai, L. Geng, Y. Liu, X. Zhang, R. Cui and Y. Ren for their work generating the genome-edited plants. Thanks to Y. Ma and Y. Zhang for data analysis. We thank Y. Gao and W. Teng for wheat outcrossing and G. Tang for gene sequencing and characterization of CENH3 expression. Thanks to M. Zong for ploidy analysis support and to W. Huang, C. Ma, Y. Pan, X. He, W. Jin, C. Gao and F. Han for technique suggestions. We thank J. Green, L. Kavanaugh, M. Rose and X. Tan for bioinformatics support and C. Leming for intellectual property guidance. We thank X. Zhang, D. Skibbe, X. Chen, J. Xu, K. White, T. Zhu, W. Cao, R. Quadt, B. Anindya, L. Shi, E. Dunder, I. Jepsen, G. Wu and B. Zhang for leadership and project guidance.
A patent covering the information in this manuscript was submitted on 2 October 2018.
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