MURAGAKI Yoshihiro
   Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine
   Position   Visiting Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Large-scale somatotopic refinement via functional synapse elimination in the sensory thalamus of developing mice.
Journal Formal name:The Journal of neuroscience
Abbreviation:J Neurosci.
Volume, Issue, Page 34(4),pp.1258-1270
Author and coauthor TAKEUCHI Yuichi†, ASANO Hidetsugu, KATAYAMA Yoko, MURAGAKI Yoshihiro, IMOTO Keiji, MIYATA Mariko
Publication date 2014/01
Summary Functional synapse elimination and strengthening are crucial developmental processes in the formation of precise neuronal circuits in the somatosensory system, but the underlying alterations in topographical organization are not yet fully understood. To address this issue, we generated transgenic mice in which afferent fibers originating from the whisker-related brain region, called the maxillary principal trigeminal nucleus (PrV2), were selectively visualized with genetically expressed fluorescent protein. We found that functional synapse elimination drove and established large-scale somatotopic refinement even after the thalamic barreloid architecture was formed. Before functional synapse elimination, the whisker sensory thalamus was innervated by afferent fibers not only from the PrV2, but also from the brainstem nuclei representing other body parts. Most notably, only afferent fibers from PrV2 onto a whisker sensory thalamic neuron selectively survived and were strengthened, whereas other afferent fibers were preferentially eliminated via their functional synapse elimination. This large-scale somatotopic refinement was at least partially dependent on somatosensory experience. These novel results uncovered a previously unrecognized role of developmental synapse elimination in the large-scale, instead of the fine-scale, somatotopic refinement even after the initial segregation of the barreloid map.
DOI 10.1523/JNEUROSCI.3865-13.2014.
PMID 24453317 23952800 [PubMed - indexed for MEDLINE]