Abstract
Parthenogenesis,the development of unfertilized egg cells into embryos,is a key component of apomixis.AtBBM(BABY BOOM),a crucial regulator of embryogenesis in Arabidopsis,possesses the capacity to shift nutritional growth toward re-productive growth.However,the mechanisms un-derlying AtBBM-induced parthenogenesis remain largely unexplored in dicot plants.Our findings re-vealed that in order to uphold the order of sexual reproduction,the embryo-specific promoter activity of AtBBM as well as repressors that inhibit its ex-pression in egg cells combine to limiting its ability to induce parthenogenesis.Notably,AtRKD5,a RWP-RK domain-containing(RKD)transcription factor,binds to the 3'end of AtBBM and is identified as one of the inhibitory factors for AtBBM expression in the egg cell.In the atrkd5 mutant,we success-fully achieved enhanced ectopic expression of AtBBM in egg cells,resulting in the generation of haploid offspring via parthenogenesis at a rate of 0.28％.Furthermore,by introducing chimeric Arabidopsis and rice BBM genes into the egg cell,we achieved a significant 4.6-fold enhance-ment in haploid induction through the atdmp8/9 mutant.These findings lay a strong foundation for further exploration of the BBM-mediated partheno-genesis mechanism and the improvement of hap-loid breeding efficiency mediated by the dmp8/9 mutant.
基金项目
Key-Area R&D Program of Guangdong Province(2022B0202060001)
National Youth Talent Program(A279021801)
Key R&D Program of Shaanxi province(2023-YBNY-008)
Natural Science Foundation of Shaanxi Province(2022JM-112)
维普
万方数据