With the rapid proliferation of RNAi applications in basic and clinical sciences, the challenge has now become understanding how components of RNAi machinery function together in a regulated manner.  Argonaute proteins are the central effectors of RNAi and are highly conserved among eukaryotes and some archaebacteria. These RNA-binding proteins use small guide RNAs to silence expression of genes at the mRNA and DNA levels.  In Argonaute Proteins: Methods and Protocols, expert researchers in this burgeoning field provide detailed, up-to-date methods to study Argonaute protein functions and interactions in a wide variety of cell types ranging from yeast to mammalian systems, as well as in vitro.  Written in the highly successful Methods in Molecular Biology™ series format, chapters include brief introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and key tips on troubleshooting and avoiding known pitfalls.  Practical and authoritative, Argonaute Proteins: Methods and Protocols serves as a vital reference for both experienced and novice scientists approaching the vast complexities of RNAi research.