Spatio-temporal dynamics of β-tubulin isotypes during the development of the sensory auditory organ in rat.

There are different β-tubulin isoforms in microtubules of vertebrate tissues. However, their functional significance is still largely unknown. In the present study, we investigated the localization of five β-tubulin isotypes (β1-5) within the hearing organ during development in rat.

Der p 1 is the primary activator of Der p 3, Der p 6 and Der p 9 the proteolytic allergens produced by the house dust mite Dermatophagoides pteronyssinus.

Background: The enzymatic activity of the four proteases found in the house dust mite Dermatophagoides pteronyssinus is involved in the pathogenesis of allergy. Our aim was to elucidate the activation cascade of their corresponding precursor forms and particularly to highlight the interconnection between proteases during this cascade.

Methods: The cleavage of the four peptides corresponding to the mite zymogen activation sites was studied on the basis of the Förster Resonance Energy Transfer method.

Differentiation of Boettcher's cells during postnatal development of rat cochlea.

Contrary to the highly specialized epithelial cells of the mammalian auditory organ, little is known about the surrounding cells and, in particular, Boettcher's cells (BC). Our morphological studies show that, in rats, these cells began their differentiation around postnatal day 8 (P8) reaching maturity around P20, when they are completely covered by Hensen's and Claudius' cells. Tight junctions were noted near the apex of BC, providing that they were in direct contact with the endolymphatic space, between approximately P8 and P16.

Evidence for a partial epithelial-mesenchymal transition in postnatal stages of rat auditory organ morphogenesis.

The epithelial-mesenchymal transition (EMT) plays a crucial role in the differentiation of many tissues and organs. So far, an EMT was not detected in the development of the auditory organ. To determine whether an EMT may play a role in the morphogenesis of the auditory organ, we studied the spatial localization of several EMT markers, the cell-cell adhesion molecules and intermediate filament cytoskeletal proteins, in epithelium of the dorsal cochlea during development of the rat Corti organ from E18 (18th embryonic day) until P25 (25th postnatal day).

Proteomic and functional characterization of a Chlamydomonas reinhardtii mutant lacking the mitochondrial alternative oxidase 1.

In the present work, we have isolated by RNA interference and characterized at the functional and the proteomic levels a Chlamydomonas reinhardtii strain devoid of the mitochondrial alternative oxidase 1 (AOX1). The AOX1-deficient strain displays a remarkable doubling of the cell volume and biomass without alteration of the generation time or change in total respiratory rate, with a significantly higher ROS production. To identify the molecular adaptation underlying these observations, we have carried out a comparative study of both the mitochondrial and the cellular soluble proteomes.