CENH3 CATD Domain Mutations for Non-Transgenic Haploid Induction

The patent applies parameter changes by modifying specific amino acid residues in the CENH3 protein sequence. Instead of substantial modifications, the invention changes specific parameters (amino acid positions) within the CATD domain to achieve haploid induction. This resolves the contradiction by achieving high induction efficiency through targeted parameter changes rather than extensive genetic modifications.

The patent applies local quality by focusing modifications specifically on the CATD domain of the CENH3 protein, particularly at specific amino acid positions. Rather than modifying the entire protein substantially, the invention makes localized changes to specific regions that are critical for haploid induction function, thereby reducing overall genetic modification complexity while maintaining effectiveness.

The patent applies this principle by using naturally occurring point mutations in the CENH3 gene that can be induced through standard mutagenesis techniques. These mutations create haploid inducer lines without requiring transgenic DNA insertion, thereby avoiding GMO classification. The solution uses simple, naturally acceptable genetic variations rather than complex transgenic constructs.

The patent applies self-service by utilizing the plant's own endogenous CENH3 gene for modification. The haploid induction capability is achieved by mutating the plant's native centromeric histone H3 gene rather than introducing foreign transgenes. This self-modification approach eliminates the need for transgenic elements and avoids public concern about GMOs while maintaining the desired haploid generation capability.

The patent applies mechanics substitution by replacing complex precision genetic engineering methods with standard mutagenesis techniques followed by screening. Instead of using sophisticated tools to precisely edit specific amino acids, the invention uses conventional mutagenesis to create random mutations and then screens for the desired haploid induction phenotype, thereby achieving reliable activity without requiring high manufacturing precision.

The patent applies preliminary action by creating a library of CENH3 mutants through mutagenesis before selecting those with haploid induction activity. This preliminary mutation step allows subsequent selection and characterization of specific amino acid substitutions that confer the desired function, achieving reliable haploid inducer activity without needing to precisely target specific residues from the outset.