Abstract: The present invention provides methods of carrying out the safe and reliable preparation of lipids comprising quaternary amines. Such lipids are especially suited for introducing therapeutic agents into cells or organisms. In particular, the lipids of the invention are suitable for the efficient transfer of gene therapy agents into mammalian cells or organisms in a cell type specific or tissue specific manner.

Abstract: The present invention provides compounds and compositions for inhibiting Vif and methods for treating viral infection, e.g., HIV infection.

Abstract: The present invention provides methods of conducting RNAi using siRNAs that are sequentially administered as single-stranded oligonucleotides. The siRNAs can be canonical or have non-canonical ends. The compositions and methods of the invention can bypass activation of interferon pathways and yet still efficiently and specifically activate RNAi/gene silencing. In another embodiment, the siRNAs of the invention are modified to allow for the calculation of certain RNAi activities, e.g., RISC activity. The invention also provides methods of using the compositions in research, diagnostic, and therapeutic applications.

Abstract: The present invention provides methods of enhancing the efficacy and specificity of RNAi by priming RISC activity in cells, cell extracts, and organisms using priming agents such as siRNAs as well as other nucleic acids. The invention also provides priming agents, extracts and cells with high levels of primed RISC activity and therefore responsiveness to RNAi, and methods of using the same in research, diagnostic, and therapeutic applications.

Abstract: The present invention relates to methods of screening for compounds that bind RNA molecules. In particular, the methods of the invention comprise screening a library of test compounds, each of which is attached to a solid support, with a dye-labeled RNA molecule to form a dye-labeled target RNA:support-attached test compound complex. By virtue of the dye label on the target RNA, the support becomes labeled and can be separated from unlabeled solid supports. The present invention further relates to methods of inhibiting an RNA-protein interaction, to methods of screening for compounds that increase or decrease the production of a protein, and to methods of screening for a compound that is capable of treating or preventing a disease whose progression is associated with an in vivo binding of a test compound to a target RNA.

Abstract: The present invention provides methods for screening and identifying compounds that inhibit a pathway affecting protein levels, and methods and compounds for treating viral, e.g., HIV, infection.

Abstract: The present invention provides methods for high-throughput screening of combinatorial libraries for specific RNA-binding compounds, using fluorescence polarization anisotropy.

Abstract: The present invention provides compositions for RNA interference and methods of use thereof. In particular, the invention provides small interfering RNAs (siRNAs) having modification that enhance the stability of the siRNA without a concomitant loss in the ability of the siRNA to participate in RNA interference (RNAi). The invention also provides siRNAs having modification that increase targeting efficiency. Modifications include chemical crosslinking between the two complementary strands of an siRNA and chemical modification of a 3? terminus of a strand of an siRNA. Preferred modifications are internal modifications, for example, sugar modification, nucleobase modification and/or backbone modifications. Such modifications are also useful, e.g., to improve uptake of the siRNA by a cell. Functional and genomic and proteomic methods are featured. Therapeutic methods are also featured.