mGluR5 regulates glutamate-dependent development of the mouse somatosensory cortex.
نویسندگان
چکیده
We have previously reported that mGluR5 signaling via PLC-beta1 regulates the development of whisker patterns within S1 (barrel) cortex of mice (Hannan et al., 2001). However, whether these defects arise from the loss of postsynaptic mGluR5 signaling, and whether the level of mGluR5 is important for barrel formation, was not examined. Furthermore, whether mGluR5 regulates other developmental processes that occur before or after barrel development is not known. We now show that mGluR5 is present postsynaptically at thalamocortical synapses during barrel formation. In addition, Mglur5(+/-) mice exhibit normal TCA patch formation but reduced cellular segregation in layer 4, indicating a dose-dependent role for mGluR5 in the regulation of pattern formation. Furthermore Mglur5(-/-) and Mglur5(+/-) mice display normal cortical arealization, layer formation, and size of PMBSF indicating the defects within S1 do not result from general abnormalities of cortical mapping during earlier stages of development. At P21 layer 4 neurons from Mglur5(-/-) and Mglur5(+/-) mice show a significant reduction in spine density but normal dendritic complexity compared with Mglur5(+/+) mice indicating a role in synaptogenesis during cortical development. Finally, mGluR5 regulates pattern formation throughout the trigeminal system of mice as the representation of the AS whiskers in the PrV, VpM, and S1 cortex was disrupted in Mglur5(-/-) mice. Together these data indicate a key role for mGluR5 at both early and late stages of neuronal development in the trigeminal system of mice.
منابع مشابه
(S)- 3,5-Dihydroxyphenylglycine )an agonist for group I metabotropic glutamate receptors( induced synaptic potentiation at excitatory synapses on fast spiking GABAergic cells in visual cortex
Introduction: (S)- 3,5-Dihydroxyphenylglycine (DHPG) is an agonist for group I metabotropic glutamate receptors. DHPG-induced synaptic depression of excitatory synapses on hippocampal pyramidal neurons is well known model for synaptic plasticity studies. The aim of the present study was to examine the effects of DHPG superfusion on excitatory synapses on pyramidal and fast-spiking GABAergic cel...
متن کاملRoles of mGluR5 in synaptic function and plasticity of the mouse thalamocortical pathway.
The group I metabotropic glutamate receptor 5 (mGluR5) has been implicated in the development of cortical sensory maps. However, its precise roles in the synaptic function and plasticity of thalamocortical (TC) connections remain unknown. Here we first show that in mGluR5 knockout (KO) mice bred onto a C57BL6 background cytoarchitectonic differentiation into barrels is missing, but the represen...
متن کاملmGluR5 in cortical excitatory neurons exerts both cell-autonomous and -nonautonomous influences on cortical somatosensory circuit formation.
Glutamatergic neurotransmission plays important roles in sensory map formation. The absence of the group I metabotropic glutamate receptor 5 (mGluR5) leads to abnormal sensory map formation throughout the mouse somatosensory pathway. To examine the role of cortical mGluR5 expression on barrel map formation, we generated cortex-specific mGluR5 knock-out (KO) mice. Eliminating mGluR5 function sol...
متن کاملPKC phosphorylation regulates mGluR5 trafficking by enhancing binding of Siah-1A.
Glutamate is the major excitatory neurotransmitter in the mammalian CNS and acts on both ionotropic and metabotropic glutamate receptors (mGluRs). The mGluRs are widely distributed in the CNS and modulate a variety of neuronal processes, including neurotransmitter release and ion channel function. In hippocampus and cortex, mGluR5 is highly expressed and plays an important role in the regulatio...
متن کاملActivity-dependent regulation of synapse and dendritic spine morphology in developing barrel cortex requires phospholipase C-beta1 signalling.
The phospholipase C-beta1 (PLC-beta1) signalling pathway, activated via metabotropic glutamate receptors (mGluRs), is implicated in activity-dependent development of the cerebral cortex, as both PLC-beta1 and mGluR5 knockout mice exhibit disrupted barrel formation in somatosensory cortex. To characterize the effects of this signalling system on development of synaptic circuitry in barrel cortex...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Journal of neuroscience : the official journal of the Society for Neuroscience
دوره 28 49 شماره
صفحات -
تاریخ انتشار 2008