title: Human Argonaute 2 Has Diverse Reaction Pathways on Target RNAs.
abstract: Argonaute is a key enzyme of various RNA silencing pathways. We use single-molecule fluorescence measurements to characterize the reaction mechanisms of the core-RISC (RNA-induced silencing complex) composed of human Argonaute 2 and a small RNA. We found that target binding of core-RISC starts at the seed region, resulting in four distinct reaction pathways: target cleavage, transient binding, stable binding, and Argonaute unloading. The target cleavage requires extensive sequence complementarity and dramatically accelerates core-RISC recycling. The stable binding of core-RISC is efficiently established with the seed match only, providing a potential explanation for the seed-match rule of miRNA (microRNA) target selection. Target cleavage on perfect-match targets sensitively depends on RNA sequences, providing an insight into designing more efficient siRNAs (small interfering RNAs).
authors.affiliation: Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea; Institute of Applied Physics, Seoul National University, Seoul 151-747, Republic of Korea; National Center of Creative Research Initiatives, Seoul National University, Seoul 151-747, Republic of Korea.
authors.forename: Myung Hyun
authors.initials: MH
authors.lastname: Jo
authors.affiliation: Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea; Institute of Applied Physics, Seoul National University, Seoul 151-747, Republic of Korea; National Center of Creative Research Initiatives, Seoul National University, Seoul 151-747, Republic of Korea.
authors.forename: Soochul
authors.initials: S
authors.lastname: Shin
authors.affiliation: Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea; Institute of Applied Physics, Seoul National University, Seoul 151-747, Republic of Korea; National Center of Creative Research Initiatives, Seoul National University, Seoul 151-747, Republic of Korea.
authors.forename: Seung-Ryoung
authors.initials: SR
authors.lastname: Jung
authors.affiliation: Department of Biological Sciences, KI for the BioCentury, KAIST, Daejeon 305-338, Republic of Korea.
authors.forename: Eunji
authors.initials: E
authors.lastname: Kim
authors.affiliation: Department of Biological Sciences, KI for the BioCentury, KAIST, Daejeon 305-338, Republic of Korea. Electronic address: songj@kaist.ac.kr.
authors.forename: Ji-Joon
authors.initials: JJ
authors.lastname: Song
authors.affiliation: Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea; Institute of Applied Physics, Seoul National University, Seoul 151-747, Republic of Korea; National Center of Creative Research Initiatives, Seoul National University, Seoul 151-747, Republic of Korea; Department of Biophysics and Chemical Biology, Seoul National University, Seoul 151-747, Republic of Korea. Electronic address: shohng@snu.ac.kr.
authors.forename: Sungchul
authors.initials: S
authors.lastname: Hohng
mesh_terms: D060565:Argonaute Proteins / Q000378:metabolism*; D001483:Base Sequence; D005453:Fluorescence; D006801:Humans; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D034743:RNA-Induced Silencing Complex / Q000235:genetics* / Q000378:metabolism
chemical_list: C466422:AGO2 protein, human; D060565:Argonaute Proteins; D035683:MicroRNAs; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex