APOBEC3DE Inhibits LINE-1 Retrotransposition by Interacting with ORF1p and Influencing LINE Reverse Transcriptase Activity

PLoS One. 2016 Jul 18;11(7):e0157220. doi: 10.1371/journal.pone.0157220. eCollection 2016.

Abstract

Human long interspersed elements 1 (LINE-1 or L1) is the only autonomous non-LTR retroelement in humans and has been associated with genome instability, inherited genetic diseases, and the development of cancer. Certain human APOBEC3 family proteins are known to have LINE-1 restriction activity. The mechanisms by which APOBEC3 affects LINE-1 retrotransposition are not all well characterized; here, we confirm that both A3B and A3DE have a strong ability to inhibit LINE-1 retrotransposition. A3DE interacts with LINE-1 ORF1p to target LINE-1 ribonucleoprotein particles in an RNA-dependent manner. Moreover, A3DE binds to LINE-1 RNA and ORF1 protein in cell culture system. Fluorescence microscopy demonstrated that A3DE co-localizes with ORF1p in cytoplasm. Furthermore, A3DE inhibits LINE-1 reverse transcriptase activity in LINE-1 ribonucleoprotein particles in a cytidine deaminase-independent manner. In contrast, A3B has less inhibitory effects on LINE-1 reverse transcriptase activity despite its strong inhibition of LINE-1 retrotransposition. This study demonstrates that different A3 proteins have been evolved to inhibit LINE-1 activity through distinct mechanisms.

MeSH terms

  • Cytidine Deaminase / metabolism*
  • HEK293 Cells
  • Humans
  • Long Interspersed Nucleotide Elements*
  • Open Reading Frames
  • RNA / genetics
  • RNA / metabolism
  • Reverse Transcription*
  • Ribonucleoproteins / genetics
  • Ribonucleoproteins / metabolism

Substances

  • Ribonucleoproteins
  • RNA
  • APOBEC3D protein, human
  • Cytidine Deaminase

Grants and funding

This work was supported by Tianjin Municipal Science and Technology Commission, Grant number: 13JCYBJC40800 (http://www.tstc.gov.cn/) to YY. The Tianjin Municipal Science and Technology Commission provided the funding for materials.