Complementary and dynamic type II cadherin expression associated with development of the primate visual system

Abstract

The middle temporal visual area (MT, also known as V5) is a visual association area that is particularly evolved in the primate brain. The MT receives input from the primary visual area (V1), constitutes part of the dorsal visual pathway, and plays an essential role in processing motion. Connections between the MT and V1 in the primate brain are formed after birth, and are related to the maturation of visual system. However, it remains to be determined what molecular mechanisms control the formation and maturation of the visual system. Cadherins are transmembrane proteins, originally isolated as cell adhesion molecules, which have multiple roles in synapse formation and function. To investigate potential involvement of cadherins in development of the primate visual system, we examined type II cadherin expression (cadherin-6, -8, -12) in cortical and thalamic visual areas of pre-and postnatal brains of the common marmoset (Callithrix jacchus). In the prenatal brain, cadherin-6 was dominantly expressed in the pulvino-MT pathway whereas cadherin-8 was dominant in the lateral geniculate nucleus (LGN)-V1 pathway. During postnatal development, there was a downregulation of cadherin-6 and upregulation of cadherin-8 expression in the MT. The timing of this cadherin exchange preceded the development of V1-MT connections. Our results suggest the possibility that changes in cadherin expression are involved in the development of the primate visual system, and that a switch in cadherin expression may be a general mechanism to control neural plasticity of highly cognitive abilities.

Complex and dynamic expression of cadherins in the embryonic marmoset cerebral cortex

“…The Cdh12 expression in the middle layer (presumptive layer IV) was seen in the temporal or occipital NCX, as previously described (Matsunaga et al . ), but not in the parietal NCX. However, by the neonatal stage, Cdh12 expression in layer IV became clear in the parietal NCX (Matsunaga et al .…”

“…We found that the expression of various cadherins differed between rodents and primates and was dynamically regulated, and in some cases, was related to the formation of primate‐specific visual circuits (Matsunaga et al . , ). Here, to explore whether primate specific expression of cadherins is seen even in the embryonic stage, we performed a more extensive spatial and temporal analysis of cadherin expressions in the developing embryonic NCX.…”

Secondary somatosensory cortex of primates: beyond body maps, toward conscious self-in-the-world maps

“…As an extension to the studies depicted in the previous section, shifts in cadherin expression patterns were detected between pulvino-MT and lateral geniculate nucleus (LGN)-V1 pathways and in the MT/V5 around the time of birth, which preceded the development of V1-MT connections, suggesting that a change in cadherin expression around the lateral sulcus may be a general mechanism to control neural plasticity in regard to higher cognitive abilities ( Fig. 5 in Matsunaga et al 2014).…”

The marmoset: An emerging model to unravel the evolution and development of the primate neocortex

“…Considerable effort has been put into characterizing the identity of the intrinsic signals that control the development of the marmoset neocortex, with the ultimate goal to associate a specific sequence of genes with each neocortical area. Groups at the RIKEN have in particular been extremely active in this domain, publishing high‐quality expression profiles of many genes in the newborn and postnatal marmoset neocortex and thalamic relay nuclei (Mashiko et al, ; Matsunaga et al, ). The RIKEN is soon to release a comprehensive online anatomical resource compiling the expression profile of a vast number of genes, following the model of the Allen Brain Atlas, increasing the exposure of the marmoset as a model for developmental neuroscience (https://gene-atlas.bminds.brain.riken.jp/).…”