Dataset Information

Induction of early Purkinje cell dendritic differentiation by thyroid hormone requires ROR?.

ABSTRACT:

Background

The active form (T3) of thyroid hormone (TH) controls critical aspects of cerebellar development, such as migration of postmitotic neurons and terminal dendritic differentiation of Purkinje cells. The effects of T3 on early dendritic differentiation are poorly understood.

Results

In this study, we have analyzed the influence of T3 on the progression of the early steps of Purkinje cell dendritic differentiation in postnatal day 0 organotypic cerebellar cultures. These steps include, successively, regression of immature neuritic processes, a stellate cell stage, and the extension of several long and mature perisomatic protrusions before the growth of the ultimate dendritic tree. We also studied the involvement of RORalpha, a nuclear receptor controlling early Purkinje cell dendritic differentiation. We show that T3 treatment leads to an accelerated progression of the early steps of dendritic differentiation in culture, together with an increased expression of RORalpha (mRNA and protein) in both Purkinje cells and interneurons. Finally, we show that T3 failed to promote early dendritic differentiation in staggerer RORalpha-deficient Purkinje cells.

Conclusions

Our results demonstrate that T3 action on the early Purkinje cell dendritic differentiation process is mediated by RORalpha.

SUBMITTER: Boukhtouche F

PROVIDER: S-EPMC2918593 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Publications

Induction of early Purkinje cell dendritic differentiation by thyroid hormone requires RORα.

Boukhtouche Fatiha F Brugg Bernard B Wehrlé Rosine R Bois-Joyeux Brigitte B Danan Jean-Louis JL Dusart Isabelle I Mariani Jean J

Neural development 20100727

<h4>Background</h4>The active form (T3) of thyroid hormone (TH) controls critical aspects of cerebellar development, such as migration of postmitotic neurons and terminal dendritic differentiation of Purkinje cells. The effects of T3 on early dendritic differentiation are poorly understood.<h4>Results</h4>In this study, we have analyzed the influence of T3 on the progression of the early steps of Purkinje cell dendritic differentiation in postnatal day 0 organotypic cerebellar cultures. These st ...[more]

PMID: 20663205

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