Functions of Rdp1 in gene-silencing processes

RNA干扰（RNAi）可以说是过去10-15年来最重要的生物学发现。这项技术在分子医学中的应用有可能彻底改变许多遗传疾病（癌症）和传染病（艾滋病，丙型肝炎）的治疗。大规模的RNAi筛选现在被用于系统地敲除许多生物体中已知基因的功能。其基本原理是，通过了解基因在正常细胞生理学背景下的功能，我们将处于更有利的位置来理解遗传疾病的分子机制。此外，RNAi可用于调节生物体中的基因表达，比通常依赖于同源重组的常规敲除技术容易得多。在植物和真菌中，RNAi依赖的基因沉默需要RNA依赖的RNA聚合酶的活性。这种酶是细胞核中染色质沉默以及细胞质中转录后基因沉默所必需的。我们的实验室致力于了解这种酶如何发挥作用，以调节细胞核和细胞质中两种遗传和生物化学上不同的基因沉默途径。这些研究的结果可能对调节商业和/或医学上重要的植物品种的基因表达有影响。

RNA interference (RNAi) is arguably the most important biological discovery of the past 10-15 years. The application of this technology to molecular medicine has the potential to revolutionize the treatment of many genetic diseases (cancer) and infectious diseases (AIDS, Hepatitis C). Large scale RNAi screens are now being used to systematically knockout the function of known genes in many organisms. The rationale is that by understanding how genes function in the context of normal cellular physiology, we will be in a stronger position to appreciate the molecular mechanisms of genetic diseases. In addition, RNAi can be used to regulate gene expression in organisms much easier than conventional knockout technologies which typically rely on homologous recombination. In plants and fungi, RNAi-dependent gene-silencing requires the activity of RNA-dependent RNA polymerase. This enzyme is required for silencing chromatin in the nucleus as well as post-transcriptional gene-silencing in the cytoplasm. Our laboratory is engaged in understanding how this enzyme functions to requlate two genetically and biochemically distinct gene-silencing pathways in the nucleus and cytoplasm. The outcome of these studies may have implications for regulating gene expression in commercially and/or medically important plant varieities.