RT Journal Article
SR Electronic
T1 Inhibitory interneurons distribute widely across the mouse thalamus and form ontogenetic spatial clusters
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 651745
DO 10.1101/651745
A1 Polona Jager
A1 Padraic Calpin
A1 Xhuljana Durmishi
A1 Irene Salgarella
A1 Tomomi Shimogori
A1 Alessio Delogu
YR 2019
UL http://biorxiv.org/content/early/2019/10/29/651745.abstract
AB The proportion and distribution of local inhibitory neurons (interneurons) in the thalamus varies widely across mammals. This is reflected in the structure of thalamic local circuits, which is more complex in primates compared to smaller-brained mammals like rodents.An increase in the number of thalamic interneurons could arise from addition of novel interneuron types or from elaboration of a plesiomorphic ontogenetic program, common to all mammals. The former has been proposed for the human brain, with migration of interneurons from the ventral telencephalon into higher order thalamus as one of its unique features (Letinic and Rakic, 2001).Here, we identify a larger than expected complexity and distribution of interneurons across the mouse thalamus. All thalamic interneurons can be traced back to two developmental programs: one specified in the midbrain and the other in the forebrain. Interneurons migrate to functionally distinct thalamic nuclei, where the midbrain-derived cells populate the sensory thalamus, and forebrain-generated interneurons only the higher order regions. The latter interneuron type may be homologous to the one previously considered to be human-specific, while we also observe that markers for the midbrain-born class are abundantly expressed in the primate thalamus. These data therefore point to a shared ontogenetic organization of thalamic interneurons across mammals.