title: FXR1a-associated microRNP: A driver of specialized non-canonical translation in quiescent conditions.
abstract: Eukaryotic protein synthesis is a multifaceted process that requires coordination of a set of translation factors in a particular cellular state. During normal growth and proliferation, cells generally make their proteome via conventional translation that utilizes canonical translation factors. When faced with environmental stress such as growth factor deprivation, or in response to biological cues such as developmental signals, cells can reduce canonical translation. In this situation, cells adapt alternative modes of translation to make specific proteins necessary for required biological functions under these distinct conditions. To date, a number of alternative translation mechanisms have been reported, which include non-canonical, cap dependent translation and cap independent translation such as IRES mediated translation. Here, we discuss one of the alternative modes of translation mediated by a specialized microRNA complex, FXR1a-microRNP that promotes non-canonical, cap dependent translation in quiescent conditions, where canonical translation is reduced due to low mTOR activity.
authors.affiliation: a Center for Cancer Research, Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA.
authors.forename: Syed I A
authors.initials: SI
authors.lastname: Bukhari
authors.affiliation: a Center for Cancer Research, Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA.
authors.forename: Shobha
authors.initials: S
authors.lastname: Vasudevan
mesh_terms: D000818:Animals; D060565:Argonaute Proteins / Q000378:metabolism*; D039603:Eukaryotic Initiation Factor-4G / Q000378:metabolism; D005095:Exoribonucleases / Q000378:metabolism; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism*; D011061:Poly A / Q000235:genetics; D011485:Protein Binding; D014176:Protein Biosynthesis; D039381:RNA Cap-Binding Proteins / Q000378:metabolism; D012315:RNA Caps / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism
chemical_list: D060565:Argonaute Proteins; D039603:Eukaryotic Initiation Factor-4G; D005095:Exoribonucleases; D051860:Fragile X Messenger Ribonucleoprotein 1; D035683:MicroRNAs; D011061:Poly A; D039381:RNA Cap-Binding Proteins; D012315:RNA Caps; D012333:RNA, Messenger; D058570:TOR Serine-Threonine Kinases
keywords: 4EBP dephosphorylation; DAP5; FXR1a; PARN; low mTOR activity; mRNA cap binding; microRNA; non-canonical translation; poly(A) shortening; quiescence