CRISPR/Cas9-mediated knockout of PiSSK1 reveals essential role of S-locus F-box protein-containing SCF complexes in recognition of non-self S-RNases during cross-compatible pollination in self-incompatible Petunia inflata

摘要: Function of Petunia PiSSK1. Self-incompatibility (SI), an inbreeding-preventing mechanism, is regulated in Petunia inflata by the polymorphic S-locus, which houses multiple pollen-specific S-locus F-box (SLF) genes and a single pistil-specific S-RNase gene. S 2-haplotype 3-haplotype possess same 17 SLF (named SLF1 to SLF17), each protein produced pollen assembled into SCF (Skp1–Cullin1–F-box) E3 ubiquitin ligase complex. A complete suite of proteins thought collectively interact with all non-self S-RNases mediate their ubiquitination degradation 26S proteasome, allowing cross-compatible pollination. For SCFSLF complex, Cullin1 subunit PiCUL1-P) Skp1 PiSSK1), like subunits (SLFs), are pollen-specific, raising possibility that they also evolved specifically function SI. Here we used CRISPR/Cas9-meditated genome editing generate frame-shift indel mutations PiSSK1 examined SI behavior T 0 plant (S 2 3) biallelic two progeny plants 2) homozygous for one alleles not carrying Cas9-containing T-DNA. Their was completely incompatible pistils seven otherwise-compatible S-genotypes, but fully compatible 3 3 transgenic production S3-RNase suppressed antisense 3-RNase gene, immature flower buds, produce little S-RNase. These results suggest functions support hypothesis SLF-containing complexes essential