RT Journal Article
SR Electronic
T1 Barentsz, a New Component of the Staufen-Containing Ribonucleoprotein Particles in Mammalian Cells, Interacts with Staufen in an RNA-Dependent Manner
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 5778
OP 5788
DO 10.1523/JNEUROSCI.23-13-05778.2003
VO 23
IS 13
A1 Paolo Macchi
A1 Sven Kroening
A1 Isabel M. Palacios
A1 Simona Baldassa
A1 Barbara Grunewald
A1 Concetta Ambrosino
A1 Bernhard Goetze
A1 Andrei Lupas
A1 Daniel St. Johnston
A1 Michael Kiebler
YR 2003
UL http://www.jneurosci.org/content/23/13/5778.abstract
AB Staufen1, the mammalian homolog of Drosophila Staufen, assembles into ribonucleoprotein particles (RNPs), which are thought to transport and localize RNA into dendrites of mature hippocampal neurons. We therefore investigated whether additional components of the RNA localization complex besides Staufen are conserved. One candidate is the mammalian homolog of Drosophila Barentsz (Btz), which is essential for the localization of oskar mRNA to the posterior pole of the Drosophila oocyte and is a component of the oskar RNA localization complex along with Staufen. In this study, we report the characterization of mammalian Btz, which behaves like a nucleocytoplasmic shuttling protein. When expressed in the Drosophila egg chamber, mammalian Btz is still able to interact with Drosophila Staufen and reach the posterior pole in the wild-type oocyte, but does not rescue the btz mutant phenotype. Most interestingly, we show by immunoprecipitation assays that Btz interacts with mammalian Staufen in an RNA-dependent manner through a conserved domain, which encompasses the region of homology to the Drosophila Btz protein and contains a novel conserved motif. One candidate for an RNA that mediates this interaction is the dendritically localized brain cytoplasmic 1 transcript. In addition, Btz and Staufen1 colocalize within particles in the cell body and, to a more variable extent, in dendrites of mature hippocampal neurons. Together, our data suggest that the mRNA transport machinery is conserved during evolution, and that mammalian Btz is an additional component of the dendritic RNPs in hippocampal neurons.