Author(s): Elva D?az
During development of the central nervous system, successive intrinsic and extrinsic programs control the specification, proliferation, and migration of individual neuronal cell types that ultimately result in the formation of precise synaptic connections. In previous research, expression profiling of the developing mouse cerebellum identified genes expressed during specific phases of neuronal differentiation. Based on this study, a novel type II transmembrane protein (SynDIG1) that regulates AMPA receptor content at developing synapses was discovered. Here I provide a detailed analysis of SynDIG1 mRNA expression in the developing mouse cerebellum. SynDIG1 mRNA is expressed exclusively in Purkinje neurons as demonstrated by analysis of Lurcher and weaver mutant mice in which Purkinje neurons or granule neurons degenerate, respectively. SynDIG1 mRNA expression is most prominent in mouse cerebellum at postnatal day 14, the peak of synaptogenesis in rodents. Interestingly, SynDIG1 mRNA appears to localize to Purkinje neuron dendrites, suggesting the intriguing possibility that SynDIG1 mRNA is subject to local protein synthesis at synapses. Taken together, these results demonstrate that SynDIG1 mRNA expression is highly dynamic with restricted expression to Purkinje neurons in the developing mouse cerebellum.