AtRKD5 inhibits the parthenogenic potential mediated by AtBBM  

作　　者：Qiyan Liu Dongfen Han Denghu Cheng Jinfan Chen Shujuan Tian Jiafa Wang Man Liu Li Yuan 

机构地区：[1]State Key Laboratory of Crop Stress Resistance and High‐Efficiency Production,College of Horticulture,Northwest A&F University,Yangling 712100,China

出　　处：《Journal of Integrative Plant Biology》2024年第7期1517-1531,共15页植物学报（英文版）

基　　金：supported by Key-Area R&D Program of Guangdong Province(2022B0202060001);the National Youth Talent Program(A279021801);Key R&D Program of Shaanxi province(2023-YBNY-008);the Natural Science Foundation of Shaanxi Province(2022JM-112).

摘　　要：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 reproductive growth.However,the mechanisms underlying AtBBM-induced parthenogenesis remain largely unexplored in dicot plants.Our findings revealed that in order to uphold the order of sexual reproduction,the embryo-specific promoter activity of AtBBM as well as repressors that inhibit its expression in egg cells combine to limiting its ability to induce parthenogenesis.Notably,AtRKD5,a RWPRK 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 successfully 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 enhancement in haploid induction through the atdmp8/9 mutant.These findings lay a strong foundation for further exploration of the BBM-mediated parthenogenesis mechanism and the improvement of haploid breeding efficiency mediated by the dmp8/9 mutant.

关 键 词：AtBBM atdmp AtRKD5 haploid induction PARTHENOGENESIS 

分 类 号：Q944.4[生物学—植物学]