Molecular and genetic analysis of novel Slicer-dependent miRNA pathways in blood

项目摘要 血液中新的Slicer依赖性miRNA通路的分子和遗传学分析 大多数保守的microRNAs（miRNAs）是通过生物合成途径产生的 将它们存放在Argonaute效应器中，引导它们到达广泛的调节靶点， 网络.在四种哺乳动物Argonautes的队列中，只有Ago 2具有催化活性， 切割转录物的能力，一种被称为“切片”的酶活性， 实验性RNA干扰然而，内源性的生物用途， 哺乳动物的切片仍然很神秘。我们以前和正在进行的研究 提供了多种切片依赖的生物发生策略的意外视角 其产生Dicer非依赖性和Dicer依赖性红细胞miRNAs。这些 数据强烈支持我们的假设，即Ago 2催化的主要用途是 在血液系统中产生特定的保守的miRNA。我们广泛的初步调查 数据是（1）一系列生物化学和基因组实验的基础，以阐明 新的切片依赖的miRNA生物发生机制，（2）新的 红系敲除动物，正常发育中的切片依赖性miRNAs，血液 稳态和白血病，以及（3）分子遗传学分析，寻求连接 Ago 2的失调过程-催化缺陷的血液系统，以特定的切片- 依赖的miRNAs。这些研究将为转录后调控带来新的见解 红细胞发育，稳态和血癌，以及查明 哺乳动物RNAi对红细胞特异性miRNA产生的功能基础。

PROJECT ABSTRACT Molecular and genetic analysis of novel Slicer-dependent miRNA pathways in blood Most conserved microRNAs (miRNAs) are generated by a biogenesis pathway that deposits them into an Argonaute effector, guiding them to broad regulatory target networks. Amongst the cohort of four mammalian Argonautes, only Ago2 has catalytic ability to cleave transcripts, an enzymatic activity known as "Slicing" that underlies experimental RNA interference. Nevertheless, the endogenous biological usage of mammalian Slicing remains largely mysterious. Our previous and ongoing studies provide the unexpected perspective of multiple Slicing-dependent biogenesis strategies that generate both Dicer-independent and Dicer-dependent erythroid miRNAs. These data strongly support our hypothesis that a dominant usage of Ago2 catalysis is to generate specific conserved miRNAs in the blood system. Our extensive preliminary data are the basis of (1) a series of biochemical and genomic experiments to elucidate a novel Slicing-dependent miRNA biogenesis mechanism, (2) genetic studies of novel knockout animals of erythroid, Slicing-dependent miRNAs in normal development, blood homeostasis and leukemia, and (3) molecular genetic analyses that seek to connect dysregulated processes in Ago2-catalytically defective blood system to specific Slicing- dependent miRNAs. These studies will bring new insights on post-transcriptional control of erythroid development, homeostasis, and blood cancer, as well as pinpoint the functional basis of mammalian RNAi to the generation of erythroid-specific miRNAs.