The delta2 glutamate receptor: 10 years later

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• The orphan glutamate receptor delta2 (GluRdelta2) is primarily found in Purkinje cells, vital for cerebellar functions.
• Mice lacking the GluRdelta2 gene exhibit ataxia and impaired synaptic plasticity, indicating its critical role.
• The exact molecular mechanisms of GluRdelta2's function in the cerebellum have been largely unknown.

Purpose of the Study:

• To elucidate the structure and function of the GluRdelta2 receptor.
• To investigate the mechanisms underlying GluRdelta2's role in cerebellar function using mutant mouse models.
• To propose hypotheses regarding GluRdelta2's function based on experimental findings.

Main Methods:

• Analysis of mutant mouse models, including lurcher, hotfoot, and GluRdelta2 knockout mice.
• Examination of GluRdelta2's channel pore structure and functionality.
• Investigation of GluRdelta2's cell surface transport and its correlation with cerebellar phenotypes.

Main Results:

• GluRdelta2 possesses a channel pore similar to other glutamate receptors, which can be functional, particularly in the presence of the lurcher mutation.
• Proper transport of GluRdelta2 to the Purkinje cell surface is necessary for its function; its absence leads to ataxia in hotfoot mice.
• GluRdelta2-null mice show potential alterations in Purkinje cell innervation by climbing fibers, possibly due to uninnervated parallel fiber spines.

Conclusions:

• GluRdelta2's function is dependent on its presence at the Purkinje cell surface.
• Mutant mouse studies provide significant insights into GluRdelta2's structure-function relationship and its role in cerebellar circuitry.
• Further research on GluRdelta2 is crucial for understanding both normal and abnormal cerebellar function and neurological disorders.