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Emmanuel Taillebourg

Publications and source records attributed to Emmanuel Taillebourg.

4 recordsLinked to original sources
PubMed2006

Peripheral myelin maintenance is a dynamic process requiring constant Krox20 expression.

Onset of myelination in Schwann cells is governed by several transcription factors, including Krox20/Egr2, and mutations affecting Krox20 result in various human hereditary peripheral neuropathies, including congenital hypomyelinating neuropathy (CHN) and Charcot-Marie-Tooth disease (CMT). Similar molecular information is not available on the process of myelin maintenance. We have generated conditional Krox20 mutations in the mouse that allowed us to develop models for CHN and CMT. In the latter case, specific inactivation of Krox20 in adult Schwann cells results in severe demyelination, involving rapid Schwann cell dedifferentiation and increased proliferation, followed by an attempt to remyelinate and a block at the promyelinating stage. These data establish that Krox20 is not only required for the onset of myelination but that it is also crucial for the maintenance of the myelinating state. Furthermore, myelin maintenance appears as a very dynamic process in which Krox20 may constitute a molecular switch between Schwann cell myelination and demyelination programs.

Alleles↗
PubMed2004

In vivo evidence for a regulatory role of the kinase activity of the linotte/derailed receptor tyrosine kinase, a Drosophila Ryk ortholog.

The RYK subfamily of receptor tyrosine kinases is characterised by unusual, but highly conserved, amino acid substitutions in the kinase domain. The linotte/derailed gene encodes a Drosophila RYK subfamily member involved in embryonic and adult central nervous system development. Previous studies have shown that the kinase activity of this receptor is not required in vivo for its embryonic function. In this study, we have investigated the role of the cytoplasmic domain and the kinase activity of the linotte/derailed receptor tyrosine kinase in adult brain development. Our results indicate that these domains are not essential for adult brain development but they are required for the proper regulation of the activity of this receptor. This sheds light on a regulatory role for the kinase activity of a RYK subfamily member.

Animals↗
PubMed2002

Mutation of linotte causes behavioral defects independently of pigeon in Drosophila.

The Drosophila linotte1 mutation was isolated from a genetic screen designed to identify learning and memory genes. For some authors, this mutation affects a novel gene specifically involved in adult learning and memory, whereas for others, it is an allele of the derailed receptor tyrosine kinase gene (the linotte/derailed gene) involved in nervous system development. Here, we show that the original derailed mutation induces a memory phenotype. We also report that a new null mutation, lioexc21, affecting specifically the linotte/derailed gene causes behavioral defects, which can be partially rescued by expression of a lio+/drl+ transgene. The data presented here suggest that the memory phenotype of linotte and derailed mutants is a consequence of abnormal brain development due to loss of function of the linotte/derailed encoded receptor tyrosine kinase.

Amino Acid Sequence↗