Genetius

The study applied a CRISPR/Cas9 multiplex guide RNA strategy to delete entire open reading frames of four reproductive genes in Arabidopsis thaliana, achieving homozygous deletions already in the T1 generation with rates of 8.3–30%. Deletion efficiencies correlated with DeepSpCas9 prediction scores, and phenotypic analyses revealed unexpected effects of residual gene fragments on fertilization and seed development.

The study demonstrates that loss of Arabidopsis metacaspase 1 (AtMC1) triggers autoimmunity reliant on downstream NLR and PRR signaling, and that overexpressing a catalytically dead AtMC1 exacerbates this effect. Overexpression of the E3 ligase SNIPER1 restores normal immunity, suggesting that AtMC1 regulates NLR protein turnover, possibly via autophagic degradation of the inactive protein.