Methods and compositions for RNA-directed target DNA modification and for RNA-directed modulation of transcription

The present disclosure provides a DNA-targeting RNA that comprises a targeting sequence and， together with a modifying polypeptide， provides for site-specific modification of a target DNA and/or a polypeptide associated with the target DNA. The present disclosure further provides site-specific modifying polypeptides. The present disclosure further provides methods of site-specific modification of a target DNA and/or a polypeptide associated with the target DNA The present disclosure provides methods of modulating transcription of a target nucleic acid in a target cell， generally involving contacting the target nucleic acid with an enzymatically inactive Cas9 polypeptide and a DNA-targeting RNA. Kits and compositions for carrying out the methods are also provided. The present disclosure provides genetically modified cells that produce Cas9; and Cas9 transgenic non-human multicellular organisms.

本公开提供一种包含靶向序列的DNA靶向RNA（DNA-targeting RNA），该RNA与修饰多肽协同，可实现靶DNA和/或与该靶DNA相关联的多肽的位点特异性修饰。本公开还提供位点特异性修饰多肽。本公开进一步提供对靶DNA和/或与该靶DNA相关联的多肽进行位点特异性修饰的方法。本公开提供了在靶细胞中调控靶核酸转录的方法，该方法通常涉及使靶核酸与酶学失活的Cas9多肽以及DNA靶向RNA接触。本公开还提供用于实施上述方法的试剂盒与组合物。本公开提供可表达Cas9的基因修饰细胞，以及携带Cas9的转基因非人类多细胞生物。