Philippe Denoulet

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Recently, we and others reported that the doublecortin gene is responsible for X-linked lissencephaly and subcortical laminar heterotopia. Here, we show that Doublecortin is expressed in the brain throughout the period of corticogenesis in migrating and differentiating neurons. Immunohistochemical studies show its localization in the soma and leading(More)
The high degree of tubulin heterogeneity in neurons is controlled mainly at the posttranslational level. Several variants of alpha-tubulin can be posttranslationally labeled after incubation of cells with [3H]acetate or [3H]glutamate. Peptides carrying the radioactive moiety were purified by high-performance liquid chromatography. Amino acid analysis, Edman(More)
A monoclonal antibody (GT335) directed against polyglutamylated tubulin was obtained by immunization with a synthetic peptide which mimics the structure of the polyglutamylated site of alpha-tubulin. This peptide corresponds to the C-terminal sequence Glu441-Gly448 and was chemically modified by the addition of two glutamyl units at Glu445. The specificity(More)
The relationship between microtubule dynamics and polyglutamylation of tubulin was investigated in young differentiating mouse brain neurons. Selective posttranslational labeling with [3H]glutamate and immunoblotting with a specific monoclonal antibody (GT335) enabled us to analyze polyglutamylation of both alpha and beta subunits. Nocodazole markedly(More)
The distribution of glutamylated tubulin has been analyzed in mammalian testis using the specific mAb GT335 by immunoelectron microscopy and immunoblotting. In spermatozoa of various species, immunogold labeling showed the presence of glutamylated tubulin in all of the microtubules of axoneme and centrioles, whereas the microtubule network of the spermatid(More)
Macronuclear DNA of the ciliate Tetrahymena pyriformis contains only one size class of fragments coding for alpha-tubulin, alpha TT. We have isolated alpha TT from a partial plasmid library, using Chlamydomonas reinhardtii alpha-tubulin gene as a probe. This gene as well as the two beta-tubulin genes, beta TT1 and beta TT2, have been sequenced. None of(More)
Interaction of rat kinesin and Drosophila nonclaret disjunctional motor domains with tubulin was studied by a blot overlay assay. Either plus-end or minus-end-directed motor domain binds at the same extent to both alpha- and beta-tubulin subunits, suggesting that kinesin binding is an intrinsic property of each tubulin subunit and that motor directionality(More)
Polyglutamylation is an important posttranslational modification of tubulin that is very active in nerve cells, where it accounts for the main factor responsible for tubulin heterogeneity. In the present work, we have analyzed quantitative and qualitative changes in glutamylated alpha- and beta-tubulin occurring during neuronal differentiation in culture.(More)
Polyglutamylation is a posttranslational modification of tubulin that is very common in neurons and ciliated or flagellated cells. It was proposed to regulate the binding of microtubule associated proteins (MAPs) and molecular motors as a function of the length of the polyglutamyl side-chain. Though much less common, this modification of tubulin also occurs(More)
Brain tubulin preparations contain an abundant type of tubulin which does not undergo the normal cycle of tyrosination-detyrosination, and whose nature is still unknown. We have used peptide sequence analysis and mass spectrometry combined with immunological procedures to show that this non-tyrosinatable tubulin has a specific primary structure. It differs(More)