4 展望
具有调控功能的小RNA 通过转录后水平、转录水平、表观遗传学水平和异染色质形成等方式调控基因组的表达，参与多种细胞过程，对个体生长发育、繁殖和遗传起至关重要的作用。通过对小RNA及其相互作用蛋白质的研究，使我们对这类新调控子的生成和作用机制、生物学功能等都有了一定的认识，但对一些新发现的小RNA，如piRNA，还需要进一步研究其生成及作用模式，如：哪些蛋白质参与piRNA 3' 端形成？新生成的piRNA是如何装载到PIWI蛋白中的？此外，尚需鉴定包括miRNA 和piRNA 在内的大部分小RNA 的生物学功能。另外，调控小RNA 的表达表现出高度的时空性，对模式生物的一些特定发育、生理或病理状态的研究，是否还会发现新类型的小RNA？通过生化和分子生物学进一步研究将逐渐解决这些问题。
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