%0 Journal Article %A Paolo Mita %A Aleksandra Wudzinska %A Xiaoji Sun %A Joshua Andrade %A Shruti Nayak %A David J. Kahler %A Sana Badri %A John LaCava %A Beatrix Ueberheide %A Chi Y. Yun %A David Fenyo %A Jef D. Boeke %T LINE-1 and the cell cycle: protein localization and functional dynamics %D 2017 %R 10.1101/147587 %J bioRxiv %P 147587 %X LINE-1/L1 retrotransposon sequences comprise 17% of the human genome. Among the many classes of mobile genetic elements, L1 is the only autonomous retrotransposon that still drives human genomic plasticity today. Through its co-evolution with the human genome, L1 has intertwined itself with host cell biology to aid its proliferation. However, a clear understanding of L1’s lifecycle and the processes involved in restricting its insertion and its intragenomic spreading remains elusive. Here we identify modes of L1 proteins’ entrance into the nucleus, a necessary step for L1 proliferation. Using functional, biochemical, and imaging approaches, we also show a clear cell cycle bias for L1 retrotransposition that peaks during the S phase. Our observations provide a basis for novel interpretations about the nature of nuclear and cytoplasmic L1 ribonucleoproteins (RNPs) and the potential role of DNA replication in L1 retrotransposition. %U https://www.biorxiv.org/content/biorxiv/early/2017/06/30/147587.full.pdf