Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK.
New Phytol. 2010 Apr;186(2):358-64. doi: 10.1111/j.1469-8137.2009.03144.x. Epub 2010 Jan 13.
Small RNAs recently emerged as ubiquitous regulators of gene expression. However, the most abundant class of small RNAs in flowering plants is poorly understood. Known as Pol IV-dependent (p4-)siRNAs, these small RNAs are associated with transcriptional gene silencing, transposable elements and heterochromatin formation. Recent research demonstrates that they are initially expressed in the maternal gametophyte and uniparentally expressed from maternal chromosomes in developing endosperm. This unique expression pattern links p4-siRNAs to double fertilization, parental genome interactions and imprinted gene expression.
小 RNA 最近被发现是基因表达的普遍调控因子。然而，在开花植物中，最丰富的小 RNA 种类还知之甚少。这些小 RNA 被称为 Pol IV 依赖性 (p4-)siRNAs，与转录基因沉默、转座元件和异染色质形成有关。最近的研究表明，它们最初在母配子体中表达，并在发育中的胚乳中从母染色体上单倍体表达。这种独特的表达模式将 p4-siRNAs 与双受精、亲本基因组相互作用和印迹基因表达联系起来。
