Two rat brain staufen isoforms differentially bind RNA

J Neurochem. 2001 Jan;76(1):155-65. doi: 10.1046/j.1471-4159.2001.00061.x.


In neurones, a limited number of mRNAs is found in dendrites, including transcripts encoding the microtubule-associated protein 2 (MAP2). Recently, we identified a cis-acting dendritic targeting element (DTE) in MAP2 mRNAs. Here we used the yeast tri-hybrid system to identify potential trans-acting RNA-binding factors of the DTE. A cDNA clone was isolated that encodes a member of a mammalian protein family that is highly homologous to the Drosophila RNA-binding protein Staufen. Mammalian Staufen appears to be expressed in most tissues and brain areas. Two distinct rat brain Staufen isoforms, rStau+I6 and rStau-I6, are encoded by alternatively spliced mRNAs. Both isoforms contain four double-stranded RNA-binding domains (dsRBD). In the larger rStau+I6 isoform, six additional amino acids are inserted in the second dsRBD. Although both isoforms interacted with the MAP2-DTE and various additional RNA fragments in an in vitro north-western assay, rStau-I6 exhibited a stronger signal of bound radioactively labelled RNAs as compared with rStau+I6. Using an antibody directed against mammalian Staufen, the protein was detected in somata and dendrites of neurones of the adult rat hippocampus and cerebral cortex. Ultrastructural studies revealed that in dendrites, rat Staufen accumulates along microtubules. Thus in neurones, rat Staufen may serve to link RNAs to the dendritic microtubular cytoskeleton and may thereby regulate their subcellular localization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alternative Splicing
  • Animals
  • Brain / metabolism*
  • Cerebral Cortex / metabolism
  • Cloning, Molecular
  • Dendrites / metabolism
  • Gene Expression Regulation, Developmental
  • Hippocampus / metabolism
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism
  • Microtubules / metabolism
  • Molecular Sequence Data
  • Organ Specificity
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • RNA / metabolism*
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / genetics*
  • RNA-Binding Proteins / metabolism*
  • Rats
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Two-Hybrid System Techniques


  • Microtubule-Associated Proteins
  • Protein Isoforms
  • RNA, Messenger
  • RNA-Binding Proteins
  • Stau1 protein, rat
  • Stau2 protein, rat
  • microtubule-associated protein 1B
  • staufen protein, mammalian
  • RNA

Associated data

  • GENBANK/AF227200
  • GENBANK/AF290989