Identification of a cis-acting dendritic targeting element in the mRNA encoding the alpha subunit of Ca2+/calmodulin-dependent protein kinase II

• Published in: The European journal of neuroscience Vol. 13; no. 10; pp. 1881 - 1888
• Main Authors: Blichenberg, Arne, Rehbein, Monika, Müller, Reinhold, Garner, Craig C., Richter, Dietmar, Kindler, Stefan
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.05.2001
• Subjects: 3' Untranslated Regions - genetics; Animals; Base Sequence - genetics; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Calcium-Calmodulin-Dependent Protein Kinases - genetics; Calcium-Calmodulin-Dependent Protein Kinases - physiology; Conserved Sequence - genetics; Dendrites - physiology; DNA, Complementary - genetics; DNA, Complementary - isolation & purification; extrasomatic protein synthesis; Isoenzymes - genetics; Isoenzymes - physiology; Molecular Sequence Data; primary rat hippocampal neurons; Rats; RNA localization; RNA, Messenger - genetics; RNA, Messenger - metabolism; Stereoisomerism; subcellular sorting; Tissue Distribution
• ISSN: 0953-816X; 1460-9568
• DOI: 10.1046/j.0953-816x.2001.01565.x

In mammalian neurons a selected group of mRNAs, including the transcript encoding the alpha subunit of Ca2+/calmodulin‐dependent protein kinase II, is found in dendrites. The molecular mechanisms underlying extrasomatic RNA trafficking are not well described. It is thought that dendritic transcripts contain cis‐acting elements that direct their selective subcellular sorting. Here we report the identification of an extrasomatic targeting element in the 3′ untranslated region of the mRNA encoding the alpha subunit of Ca2+/calmodulin‐dependent protein kinase II. In primary hippocampal neurons, this 1200‐nucleotide‐spanning, cis‐acting element is sufficient to mediate dendritic localization of chimeric reporter transcripts. The trafficking signal does not share any striking sequence similarity with a previously characterized dendritic targeting element in transcripts encoding the microtubule‐associated protein 2. In dendrites of transfected primary neurons, recombinant RNAs form granules with an average diameter of 0.45 µm that may represent preferential RNA docking sites or multimolecular transport units. These findings imply that extrasomatic sorting of individual dendritic mRNAs involves at least partially distinct molecular mechanisms, as well as large trafficking complexes.