TY - JOUR
T1 - Differential distribution of Rac1 and Rac3 GTPases in the developing mouse brain
T2 - Implications for a role of Rac3 in Purkinje cell differentiation
AU - Bolis, Annalisa
AU - Corbetta, Sara
AU - Cioce, Antonella
AU - De Curtis, Ivan
PY - 2003/11
Y1 - 2003/11
N2 - Rac3 is one of the three known Rac GTPases in vertebrates. Rac3 shows high sequence homology to Rac1, and its transcript is specifically expressed in the developing nervous system, where its localization and function are unknown. By using Rac3-specific antibodies, we show that the endogenous Rac3 protein is differentially expressed during mouse brain development, with a peak of expression at times of neuronal maturation and synaptogenesis. Comparison with Rac1 shows clear-cut differences in the overall distribution of the two GTPases in the developing brain, and in their subcellular distribution in regions of the brain where both proteins are expressed. At P7, Rac3 staining is particularly marked in the deep cerebellar nuclei and in the pons, where it shows a discontinuous distribution around the neuronal cell bodies, in contrast with the diffuse staining of Rac1. Rac3 does not evidently co-localize with preand post-synaptic markers, nor with GFAP-positive astrocytes, but it clearly co-localizes with actin filaments, and with the terminal portions of calbindin-positive Purkinje cell axons in the deep cerebellar nuclei. Our data implicate Rac3 in neuronal differentiation, and support a specific role of this GTPase in actin-mediated remodelling of Purkinje cell neuritic terminals at time of synaptogenesis.
AB - Rac3 is one of the three known Rac GTPases in vertebrates. Rac3 shows high sequence homology to Rac1, and its transcript is specifically expressed in the developing nervous system, where its localization and function are unknown. By using Rac3-specific antibodies, we show that the endogenous Rac3 protein is differentially expressed during mouse brain development, with a peak of expression at times of neuronal maturation and synaptogenesis. Comparison with Rac1 shows clear-cut differences in the overall distribution of the two GTPases in the developing brain, and in their subcellular distribution in regions of the brain where both proteins are expressed. At P7, Rac3 staining is particularly marked in the deep cerebellar nuclei and in the pons, where it shows a discontinuous distribution around the neuronal cell bodies, in contrast with the diffuse staining of Rac1. Rac3 does not evidently co-localize with preand post-synaptic markers, nor with GFAP-positive astrocytes, but it clearly co-localizes with actin filaments, and with the terminal portions of calbindin-positive Purkinje cell axons in the deep cerebellar nuclei. Our data implicate Rac3 in neuronal differentiation, and support a specific role of this GTPase in actin-mediated remodelling of Purkinje cell neuritic terminals at time of synaptogenesis.
KW - Deep cerebellar nuclei
KW - Development
KW - Neuritogenesis
KW - Rho family GTPases
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U2 - 10.1046/j.1460-9568.2003.02938.x
DO - 10.1046/j.1460-9568.2003.02938.x
M3 - Article
C2 - 14622142
AN - SCOPUS:0345305736
VL - 18
SP - 2417
EP - 2424
JO - European Journal of Neuroscience
JF - European Journal of Neuroscience
SN - 0953-816X
IS - 9
ER -