Researchers from the MRC Centre for Developmental Neurobiology (MRC CDN), led by Prof. Oscar Marín, have identified the mechanisms guiding interneurons to the striatum, a major brain centre involved in the coordination of body movement and motivation. These results, published in Journal of Neuroscience in collaboration with investigators from the Instituto de Neurociencias in Alicante (Spain), also reveal the molecular nature of the cues regulating the migration of striatal interneurons.
During development, the medial ganglionic eminence (MGE), a transitory brain structure, produces several populations of GABAergic inhibitory neurons, including cortical and striatal interneurons. While most research studies have focused on the migration of interneurons to the cortex, very little is known about the mechanisms by which interneurons colonise the striatum. Both cortical and striatal interneurons can be attracted by Nrg1 sources present in the cerebral cortex and the striatum. Therefore, the segregation of these two populations of interneurons must depend on repulsive signals that prevent the colonization of regions outside their final target.
Experiments carried out by the group of Prof. Marín demonstrated that striatal interneurons are repelled by the cerebral cortex through a mechanism that involves Eph/ephrin signalling. This new study also shows that the responsiveness of MGE-derived striatal interneurons to attractive and repulsive cues is, at least in part, controlled by the postmitotic activity of the transcription factor Nkx2-1. These results reveal parallel mechanisms of target chemoattraction and off-target chemorepulsion for the migration of interneurons to the cortex and striatum.
This work was supported by grants from the Spanish Ministry of Economy SAF2011- 28845 and CONSOLIDER CSD2007-00023.
Original publication: Villar-Cerviño V., Kappeler C., Nóbrega-Pereira S., Henkemeyer M., Rago L., Nieto MA. & Marín O. (2015) Molecular Mechanisims Controlling the Migration of Striatal Interneurons. J Neurosci, in press.
For further information please contact Andreia Carvalho, Head of Scientific Affairs, MRC Centre for Developmental Neurobiology, King’s College London ( firstname.lastname@example.org )