无患子雄性不育品种'琦蕊'不同发育时期雄花转录组分析OA北大核心CSTPCD

[Objective]The objective of this work is to observe the cytological characteristics of the anther development in the male sterile Sapindus mukorossi'Qirui',identify differentially expressed genes(DEGs)during the critical period of anther development,which provides a theoretical basis for deeply analyzing the molecular mechanism of the male sterility.[Method]By examining the cytological features of male anther development stages,RNA-Seq technology was used to compare the transcriptome of male buds at different stages:microspore mother cell stage(T1),tetrad stage(T2)and mononuclear microspore stage(T3),to identify key DEGs.[Result]The study revealed that the continuous expansion and proliferation of'Qirui'tapetum and endothecium led to a chaotic anthecium structure and insufficient anthecium space,resulting in abortive pollen.Additionally,a decrease in the level of jasmonic acid(JA)from endogenous hormone determination was observed during male bud development.A total of 2 990 DEGs were detected through transcriptome analysis at the three anther development stages,of which 722 in T2_vs_T1(516 up-regulated and 206 down-regulated),and 1 741 in T3_vs_T2(765 up-regulated,976 down-regulated).GO and KEGG analysis showed that these DEGs were primarily enriched in metabolic processes,cell division,pollen wall synthesis,hormone signal transduction,etc.Specifically,32 DEGs were associated with pollen development,and 27 DEGs were linked to hormone synthesis and signal transduction.Nine DEGs were randomly selected for RT-qPCR analysis,and the results were consistent with the trend of RNA-Seq data,which proved the accuracy of transcriptome data.[Conclusion]The continuous proliferation of tapetum,delayed degeneration of endothecium,and continuous extrusion of microspores are the key factors leading to male sterility in S.mukorossi'Qirui'.Overall,genes related to material metabolism,cell division,hormone level and pollen development play crucial roles in the mechanism of male sterility.