title: A 3' Poly(A) Tract Is Required for LINE-1 Retrotransposition.
abstract: L1 retrotransposons express proteins (ORF1p and ORF2p) that preferentially mobilize their encoding RNA in cis, but they also can mobilize Alu RNA and, more rarely, cellular mRNAs in trans. Although these RNAs differ in sequence, each ends in a 3' polyadenosine (poly(A)) tract. Here, we replace the L1 polyadenylation signal with sequences derived from a non-polyadenylated long non-coding RNA (MALAT1), which can form a stabilizing triple helix at the 3' end of an RNA. L1/MALAT RNAs accumulate in cells, lack poly(A) tails, and are translated; however, they cannot retrotranspose in cis. Remarkably, the addition of a 16 or 40 base poly(A) tract downstream of the L1/MALAT triple helix restores retrotransposition in cis. The presence of a poly(A) tract also allows ORF2p to bind and mobilize RNAs in trans. Thus, a 3' poly(A) tract is critical for the retrotransposition of sequences that comprise approximately one billion base pairs of human DNA.
authors.affiliation: Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109-5618, USA. Electronic address: adoucet@umich.edu.
authors.forename: Aurélien J
authors.initials: AJ
authors.lastname: Doucet
authors.affiliation: Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
authors.forename: Jeremy E
authors.initials: JE
authors.lastname: Wilusz
authors.affiliation: Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109-5618, USA.
authors.forename: Tomoichiro
authors.initials: T
authors.lastname: Miyoshi
authors.affiliation: Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, MI 48109-5618, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109-5618, USA; Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109-5618, USA; Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, MI 48109-5618, USA. Electronic address: moranj@umich.edu.
authors.forename: John V
authors.initials: JV
authors.lastname: Moran
mesh_terms: D004720:Endonucleases / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D020084:Long Interspersed Nucleotide Elements; D011061:Poly A / Q000378:metabolism*; D062085:RNA, Long Noncoding / Q000378:metabolism; D012333:RNA, Messenger / Q000737:chemistry* / Q000235:genetics; D012194:RNA-Directed DNA Polymerase / Q000235:genetics
chemical_list: C557041:MALAT1 long non-coding RNA, human; C531246:ORF2 protein, human; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D011061:Poly A; D012194:RNA-Directed DNA Polymerase; D004720:Endonucleases