LINE-1 and the cell cycle: protein localization and functional dynamics

Mita, P.; Wudzinska, A.; Sun, X.; Andrade, J.; Nayak, S.; Kahler, D.; Badri, S.; LaCava, J.; Ueberheide, B.; Yun, C.; Fenyo, D.; Boeke, J.

doi:10.1101/147587

bioRxiv · 10.1101/147587

LINE-1 and the cell cycle: protein localization and functional dynamics

Mita, P.·Wudzinska, A.·Sun, X.·Andrade, J.·Nayak, S.·Kahler, D.·Badri, S.·LaCava, J.·Ueberheide, B.·Yun, C.·Fenyo, D.·Boeke, J.

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Abstract

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 L1s 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.

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Mita, P., Wudzinska, A., Sun, X., Andrade, J., Nayak, S., Kahler, D., Badri, S., LaCava, J., Ueberheide, B., Yun, C., Fenyo, D., Boeke, J.. 2017-06-30. LINE-1 and the cell cycle: protein localization and functional dynamics. https://doi.org/10.1101/147587

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