关键词: 芦笋, 两性花, 雄花, 性别分化, 可变剪接

Abstract:

Alternative splicing plays an important role in plant growth and development，which causes the same mRNA precursor for turning into different isoforms and producing protein diversity. To analyze the relationship of alternative splicing of Asparagus officinalis L. and the sex differentiation，the alternative splicing occurring in hermaphroditic flower buds and male flower buds were identified using RNA-seq technology. The results showed that a large number of alternative splicing events were identified in hermaphroditic flower buds and male flower buds. The dominated alternative splicing types were the 3′ splice site selection and exon skipping. The GO annotation showed that the shared alternative splicing genes by hermaphroditic flower buds and male flower buds mainly enriched in metabolic processes，biosynthetic process，cellular components and material-associated entries. The results of GO and KEGG analysis showed that the specific alternative splicing genes were significantly enriched in metabolic pathway，nitrogen compound metabolic process，peroxisome and oxidative phosphorylation pathway for hermaphroditic flower buds. The nitrogen compound metabolic process and the activities of antioxidant enzymes were probably related to the development of the asparagus pistil. For male flowers，the specific alternative splicing genes were significantly enriched in metabolic pathways，biosynthesis of secondary metabolites and the lipid metabolic process such as fatty acid biosynthesis. There was a possibility that the lipid metabolic process could lead to the suspension of pistil development in male flowers of asparagus. The results of this study not only provided a theoretical basis for regulating the formation of hermaphroditic flowers，but also for studying deeply the molecular mechanism of sex differentiation and sex determination in Asparagus officinalis L.

Key words: Asparagus officinalis, hermaphroditic flower, male flower, sex differentiation, alternative splicing