Key message

MiRNA transcriptome analysis of different tissues in poplar and larch suggests variant roles of miRNAs in regulating wood formation between two kinds of phyla.

Abstract

Poplar and larch belong to two different phyla. Both are ecological woody species and major resources for wood-related industrial applications. However, wood properties are different between these two species and the molecular basis is largely unknown. In this study, we performed high-throughput sequencing of microRNAs (miRNAs) in the three tissues, xylem, phloem and leaf of Populus alba × Populus glandulosa and Larix kaempferi. Differentially expressed miRNA (DEmiRNA) analysis identified 85 xylem-specific miRNAs in P. alba × P. glandulosa and 158 xylem-specific miRNAs in L. kaempferi. Among 36 common miRNAs, 12 were conserved between the two species. GO and KEGG analyses of the miRNA target genes showed similar metabolism in two species. Through KEGG and BLASTN, we predicted target genes of xylem differentially expressed (DEmiRNA) in the wood formation-related pathways and located DEmiRNAs in these pathways. A network was built for wood formation-related DEmiRNAs, their target genes and orthologous genes in Arabidopsis thaliana. Comparison of DEmiRNA and target gene annotation between P. alba × P. glandulosa and L. kaempferi suggested the different functions of DEmiRNAs and divergent mechanism in wood formation between two species, providing knowledge to understand wood formation mechanism in gymnosperm and angiosperm woody plants.

中文翻译：

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杨树和落叶松之间的 MicroRNA 比较提供了对木材形成不同机制的深入了解。

关键信息

杨树和落叶松不同组织的 miRNA 转录组分析表明 miRNA 在调节两种门之间木材形成中的不同作用。

抽象的

杨树和落叶松属于两个不同的门。两者都是生态木本物种和木材相关工业应用的主要资源。然而，这两个物种之间的木材特性不同，分子基础在很大程度上是未知的。在这项研究中，我们对白杨 ×  Populus glandulosa和落叶松的木质部、韧皮部和叶这三种组织中的 microRNA (miRNA) 进行了高通量测序。差异表达的 miRNA (DEmiRNA) 分析鉴定了P. alba  ×  P. glandulosa中的 85 种木质部特异性 miRNA 和L. kaempferi中的 158 种木质部特异性 miRNA 。在 36 个常见的 miRNAs 中，12 个在两个物种之间是保守的。对 miRNA 靶基因的 GO 和 KEGG 分析显示两个物种的代谢相似。通过KEGG和BLASTN，我们预测了木材形成相关通路中木质部差异表达（DEmiRNA）的靶基因，并在这些通路中定位了DEmiRNA。为拟南芥中木材形成相关的DEmiRNA、它们的靶基因和直系同源基因建立了一个网络。P. alba  ×  P. meadowulosa和L. kaempferi的 DEmiRNA 和靶基因注释的比较提出了DEmiRNA的不同功能和两个物种之间木材形成的不同机制，为了解裸子植物和被子植物木本植物的木材形成机制提供了知识。