The steroid receptor RNA activator is the first functional RNA encoding a protein

FEBS Lett. 2004 May 21;566(1-3):43-7. doi: 10.1016/j.febslet.2004.03.104.


The steroid receptor RNA activator (SRA) has previously been characterized as belonging to the growing family of functional non-coding RNAs. However, we recently reported the Western blot detection of a putative endogenous SRA protein (SRAP) in breast cancer cells. Herein, we successfully suppressed the expression of this protein through specific RNA interference assay, unequivocally confirming its existence. Moreover, using database searches and Western blot analysis, we also showed that SRAP is highly conserved among chordata. Overall, our results suggest that SRA is the first example of a new class of functional RNAs also able to encode a protein.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Blotting, Western
  • Conserved Sequence
  • HeLa Cells
  • Humans
  • Molecular Sequence Data
  • Muscle, Skeletal / metabolism
  • Protein Biosynthesis / genetics*
  • RNA Interference / physiology
  • RNA, Long Noncoding
  • RNA, Untranslated / genetics*
  • Rats
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Sequence Alignment
  • Species Specificity
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism*
  • Transfection


  • RNA, Long Noncoding
  • RNA, Untranslated
  • Recombinant Proteins
  • Sra1 protein, rat
  • Transcription Factors
  • steroid receptor RNA activator