Final answer:
RNABP Staufen is a protein that mediates RNA transport within cells, playing a pivotal role in the post-transcriptional regulation of gene expression by ensuring proper mRNA localization and timing for translation.
Step-by-step explanation:
The RNA binding protein Staufen (RNABP Staufen) plays a crucial role in post-transcriptional regulation of gene expression, specifically mediating RNA transport within cells. Staufen binds to mRNA and is involved in various aspects of mRNA metabolism, including its transport, localization, and regulated translation. This localization is essential for the spatial and temporal control of gene expression, particularly in the development of organisms and in neuronal cells where localized translation of mRNAs is necessary for synaptic plasticity. RNABP Staufen does not assist in DNA replication or catalyze protein synthesis directly, but it ensures that mRNAs are properly transported and available for translation by ribosomes at the correct time and place.