Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China.
Planta. 2013 Oct;238(4):739-52. doi: 10.1007/s00425-013-1929-6. Epub 2013 Jul 13.
Plant microRNAs (miRNAs) post-transcriptionally regulate target gene expression to modulate growth and development and biotic and abiotic stress responses. By analyzing small RNA deep sequencing data in combination with the genome sequence, we identified 75 conserved miRNAs and 11 novel miRNAs. Their target genes were also predicted. For most conserved miRNAs, the miRNA-target pairs were conserved across plant species. In addition to these conserved miRNA-target pairs, we also identified some papaya-specific miRNA-target regulatory pathways. Both miR168 and miR530 target the Argonaute 1 gene, indicating a second autoregulatory mechanism for miRNA regulation. A non-conserved miRNA was mapped within an intron of Dicer-like 1 (DCL1), suggesting a conserved homeostatic autoregulatory mechanism for DCL1 expression. A 21-nt miRNA triggers secondary siRNA production from its target genes, nucleotide-binding site leucine-rich repeat protein genes. Certain phased-miRNAs were processed from their conserved miRNA precursors, indicating a putative miRNA evolution mechanism. In addition, we identified a Carica papaya-specific miRNA that targets an ethylene receptor gene, implying its function in the ethylene signaling pathway. This work will also advance our understanding of miRNA functions and evolution in plants.
植物 microRNAs (miRNAs) 通过转录后调控靶基因的表达，从而调节生长发育和生物及非生物胁迫反应。通过分析小 RNA 深度测序数据并结合基因组序列，我们鉴定了 75 个保守 miRNAs 和 11 个新的 miRNAs。我们还预测了它们的靶基因。对于大多数保守的 miRNAs，miRNA-靶对在植物物种间是保守的。除了这些保守的 miRNA-靶对，我们还鉴定了一些番木瓜特有的 miRNA-靶调控途径。miR168 和 miR530 都靶向 Argonaute 1 基因，这表明 miRNA 调控的第二个自我调控机制。一个非保守的 miRNA 被映射到 Dicer-like 1 (DCL1) 的内含子中，这表明 DCL1 表达的保守的自我平衡的自我调控机制。一个 21-nt 的 miRNA 从其靶基因核苷酸结合位点富含亮氨酸重复蛋白基因触发二级 siRNA 的产生。某些相移 miRNA 是从其保守的 miRNA 前体中加工而来的，这表明了一种潜在的 miRNA 进化机制。此外，我们鉴定了一个番木瓜特有的 miRNA，它靶向乙烯受体基因，暗示其在乙烯信号通路中的功能。这项工作也将促进我们对植物中 miRNA 功能和进化的理解。
