hCLE/C14orf166 associates with DDX1-HSPC117-FAM98B in a novel transcription-dependent shuttling RNA-transporting complex

PLoS One. 2014 Mar 7;9(3):e90957. doi: 10.1371/journal.pone.0090957. eCollection 2014.

Abstract

hCLE/C14orf166 is a nuclear and cytoplasmic protein that interacts with the RNAP II, modulates nuclear RNA metabolism and is present in cytoplasmic RNA granules involved in localized translation. Here we have studied whether hCLE shares common interactors in the nucleus and the cytosol, which could shed light on its participation in the sequential phases of RNA metabolism. Nuclear and cytoplasmic purified hCLE-associated factors were identified and proteins involved in mRNA metabolism, motor-related proteins, cytoskeletal and translation-related factors were found. Purified hCLE complexes also contain RNAs and as expected some hCLE-interacting proteins (DDX1, HSPC117, FAM98B) were found both in the nucleus and the cytoplasm. Moreover, endogenous hCLE fractionates in protein complexes together with DDX1, HSPC117 and FAM98B and silencing of hCLE down-regulates their nuclear and cytosolic accumulation levels. Using a photoactivatable hCLE-GFP protein, nuclear import and export of hCLE was observed indicating that hCLE is a shuttling protein. Interestingly, hCLE nuclear import required active transcription, as did the import of DDX1, HSPC117 and FAM98B proteins. The data indicate that hCLE probably as a complex with DDX1, HSPC117 and FAM98B shuttles between the nucleus and the cytoplasm transporting RNAs suggesting that this complex has a prominent role on nuclear and cytoplasmic RNA fate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus / genetics*
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism
  • Cell Nucleus / metabolism
  • Cytoplasm / metabolism
  • DEAD-box RNA Helicases / genetics
  • DEAD-box RNA Helicases / metabolism*
  • Gene Expression Regulation
  • Genetic Vectors
  • HEK293 Cells
  • Humans
  • Lentivirus / genetics
  • Molecular Sequence Annotation
  • Protein Binding
  • Protein Multimerization
  • Proteins / genetics
  • Proteins / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • Signal Transduction
  • Trans-Activators / genetics
  • Trans-Activators / metabolism*
  • Transcription, Genetic

Substances

  • Carrier Proteins
  • FAM98B protein, human
  • Proteins
  • RNA, Messenger
  • RTCB protein, human
  • RTRAF protein, human
  • Trans-Activators
  • DDX1 protein, human
  • DEAD-box RNA Helicases

Grants and funding

This work was supported by the Ministerio de Ciencia e Innovación, Plan Nacional de Investigacion Científica, Desarrollo e Innovación Tecnólogica (BFU2008-00448 and BFU2011-26175), Instituto de Salud Carlos III (Programa especial de investigación sobre la gripe pándemica GR09/0023, GR09/0040, GR09/0039), the Spanish National Proteomics Institute (ProteoRed-ISC III) (grant number 2005X747_3) and Ciber de Enfermedades Respiratorias. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.