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Article

  • The EMBO Journal (2008) 27, 3024 - 3035
  • doi:10.1038/emboj.2008.221

Published online: 23 October 2008

RNA-dependent recruitment of the origin recognition complex

Julie Norseen1, Andreas Thomae2, Venkatesh Sridharan3, Ashok Aiyar3, Aloys Schepers2 and Paul M Lieberman1

  1. Program in Gene Expression and Regulation, The Wistar Institute, Philadelphia, PA, USA
  2. Department of Gene Vectors, National Research Center for Environment and Health, Munchen, Germany
  3. Department of Microbiology, LSU Health Sciences Center, New Orleans, LA, USA

Correspondence to:

Paul M Lieberman, Gene Regulation, The Wistar Institute, University of Pennsylvania, 3601 Spruce Street, Philadelphia, PA 19104, USA. Tel.: +1 215 898 9491; Fax: +1 215 898 0663; E-mail: Lieberman@wistar.org

Received 30 May 2008; Accepted 23 September 2008

The origin recognition complex (ORC) has an important function in determining the initiation sites of DNA replication. In higher eukaryotes, ORC lacks sequence-specific DNA binding, and the mechanisms of ORC recruitment and origin determination are poorly understood. ORC is recruited with high efficiency to the Epstein–Barr virus origin of plasmid replication (OriP) through a complex mechanism involving interactions with the virus-encoded EBNA1 protein. We present evidence that ORC recruitment to OriP and DNA replication function depends on RGG-like motifs, referred to as LR1 and LR2, in the EBNA1 amino-terminal domain. Moreover, we show that LR1 and LR2 recruitment of ORC is RNA dependent. HMGA1a, which can functionally substitute for LR1 and LR2 domain, can also recruit ORC in an RNA-dependent manner. EBNA1 and HMGA1a RGG motifs bound to structured G-rich RNA, as did ORC1 peptides, which interact with EBNA1. RNase A treatment of cellular chromatin released a fraction of the total ORC, suggesting that ORC association with chromatin, and possibly cellular origins, is stabilized by RNA. We propose that structural RNA molecules mediate ORC recruitment at some cellular and viral origins, similar to OriP.

  • Keywords:

    • EBNA1,
    • ORC,
    • replication,
    • RNA binding