RRC ID 528
Author Osanai M, Takahashi H, Kojima KK, Hamada M, Fujiwara H.
Title Essential motifs in the 3' untranslated region required for retrotransposition and the precise start of reverse transcription in non-long-terminal-repeat retrotransposon SART1.
Journal Mol Cell Biol
Abstract Non-long-terminal-repeat (non-LTR) retrotransposons amplify their copies by reverse transcribing mRNA from the 3' end, but the initial processes of reverse transcription are still unclear. We have shown that a telomere-specific non-LTR retrotransposon of the silkworm, SART1, requires the 3' untranslated region (3' UTR) for retrotransposition. With an in vivo retrotransposition assay, we identified several novel motifs within the 3' UTR involved in precise and efficient reverse transcription. Of 461 nucleotides (nt) of the 3' UTR, the central region, from nt 163 to nt 295, was essential for SART1 retrotransposition. Of five putative stem-loops formed in RNA for the SART1 3' UTR, the second stem-loop (nt 159 to 221) is included in this region. Loss of the 3' region (nt 296 to 461) in the 3' UTR and the poly(A) tract resulted in decreased and inaccurate reverse transcription, which starts mostly from several telomeric repeat-like GGUU sequences just downstream of the second stem-loop. These results suggest that short telomeric repeat-like sequences in the 3' UTR anneal to the bottom strand of (TTAGG)(n) repeats. We also demonstrated that the mRNA for green fluorescent protein (GFP) could be retrotransposed into telomeric repeats when the GFP coding region is fused with the SART1 3' UTR and SART1 open reading frame proteins are supplied in trans.
Volume 24(18)
Pages 7902-13
Published 2004-9-1
DOI 10.1128/MCB.24.18.7902-7913.2004
PII 24/18/7902
PMID 15340053
PMC PMC515065
MeSH 3' Untranslated Regions* Animals Base Sequence Bombyx / genetics* Cell Line Green Fluorescent Proteins Luminescent Proteins / genetics Models, Genetic Molecular Sequence Data Mutation Nucleic Acid Conformation Nucleopolyhedroviruses / genetics RNA / chemistry RNA / genetics RNA, Messenger / genetics Recombinant Proteins / genetics Retroelements / genetics* Sequence Deletion Spodoptera Telomere / genetics Transcription, Genetic
IF 3.611
Times Cited 28
Silkworms ?