摘要
Clustered regularly interspaced short palindromic repeats(CRISPR)-Cas systems can be engineered as programmable transcription factors to either activate(CRISPRa)or inhibit transcription.Apomixis is extremely valuable for the seed industry in breeding clonal seeds with pure genetic backgrounds.We report here a CRISPR/dCas9-based toolkit equippedwith dCas9-VP64 andMS2-p65-HSF1 effectors that may specifically target genes with high activation capability.We explored the application of in vivo CRISPRa targeting of maize BABY BOOM2(ZmBBM2),acting as a fertilization checkpoint,as a means to engineer parthenogenesis.We detected ZmBBM2 transcripts only in egg cells but not in other maternal gametic cells.Activation of ZmBBM2 in egg cells in vivo caused maternal cell-autonomous parthenogenesis to produce haploid seeds.Our work provides a highly specific gene-activation CRISPRa technology for target cells and verifies its application for parthenogenesis induction in maize.
基金
supported by the National Science Foundation of China(32001551 and 31771808)
the China Postdoctoral Science Foundation(2020M680779)
the Agricultural Science and Technology Innovation Program of the CAAS(S2022ZD03)
Hainan Yazhou Bay Seed Laboratory(B21HJ0215).
