柳属植物花发育相关的MADS-box基因家族成员鉴定与表达分析

Identification and expression analysis of flower development-related MADS-box gene family members in Salix

【目的】利用基因组和转录组数据鉴定分析花发育相关的MADS-box基因家族成员的结构特征及表达模式,为柳属花被缺失的分子机制研究提供理论依据。【方法】通过生物信息学方法鉴定柳属的长梗柳(Salix dunnii)、欧蒿柳(S.viminalis)、红皮柳(S.purpurea)的MADS-box基因家族成员,并对3种柳树花发育相关的MADS-box基因系统发育关系、基因复制和丢失、基因结构和理化性质进行分析。根据雌雄花芽的转录组数据分析长梗柳花发育相关基因在花芽不同发育阶段的表达模式。【结果】在长梗柳、欧蒿柳和红皮柳中分别鉴定出82、82和98个MADS-box家族基因。3种柳树的花发育相关基因经历了基因复制和丢失,相同亚类基因结构和保守结构域相似,但部分A、B、C和E亚类基因的K-box结构域缺失。长梗柳花发育相关基因的表达结果显示,在雌花和雄花中具有不同的表达模式。其中,B亚类SdMADS26和SdMADS4基因表达量均偏低。【结论】柳属植物花发育相关基因中部分成员的基因结构和表达模式发生了变化,推测这些变化可能与柳属花被缺失相关。

【Objective】Flower development-related MADS-box genes in Salix were identified and analyzed for structure and expression pattern with genomes and transcriptome data.This work will lay the theoretical foundation for exploring the molecular mechanism of perianth loss of Salix species.【Method】The MADS-box family genes in three Salix species(S.dunnii,S.viminalis and S.purpurea) were identified by bioinformatics method and then analyzed for phylogeny,gene duplication/loss,gene structure and physicochemical property.In addition,the expression patterns of MADS-box genes in S.dunnii at different inflorescence development stages were analyzed with transcriptome data of female and male flower buds.【Result】A total of 82,82 and 98 MADS-box family genes were identified in S.dunnii,S.viminalis and S.purpurea,respectively,and gene duplication and loss were detected in three species.The structures and conserved domains of MADS-box genes in the same subclass were similar,while some genes of subclass A,B,C and E lacked K-box domain.The MADS-box genes showed differential expression patterns in female and male flowers of S.dunnii.However,SdMADS26 and SdMADS4 gene belonging to subclass B showed low expression in both female and male flowers.【Conclusion】The results above suggested that the changes in the structure and gene expression of some MADS-box genes may contributed to perianth loss in Salix.