This article in Neuron published by Buckley et al. describes findings in explanted and cultured neurons (ex vivo) that intron-retained, repetitive sequences, so-called identifier elements (ID elements), confer dendritic targeting competence to neuronal transcripts, partially in agreement with previous ex-vivo findings by Muslimov et al. (Muslimov et al., 1997
). However, the in-vivo findings by our group using transgenic mouse models do not support the idea that ID elements could act as dendritic targeting elements for mRNAs (Khanam et al., 2007
). The authors have claimed that the position of the ID elements in a transcript is crucial for such a phenomenon, and that the location of the ID elements in 3’ UTR is not ideal. This is quite intriguing, as most of the dendritc targeting elements identified so far are located in 3’ UTRs.
It is noteworthy that ID elements are restricted to the mammalian order of rodentia (rodents). The question of whether a similar mechanism, if it exists at...