Abstract

Jennifer Saussede-Aim*and Charles Dumontet

Tubulin is the main constituent of microtubules, a macromolecule participating in a variety of essential cell phenomena. Although the roles of microtubules have been extensively described, the regulation of tubulin expression remains largely unexplored. This review gives an overall view of the regulatory mechanisms of tubulin expression reported in the literature. The first model proposed to explain the regulation of tubulin expression was based on an auto-regulatory mechanism. This hypothesis suggests that soluble tubulin pools regulate the tubulin mRNA levels. This is due to the MREI sequence common to all -tubulin isotypes. Nevertheless this model does not explain variations specific for each tubulin isotype. Transcriptional regulation has been suggested in multiple models. Indeed it appears that certain isotypes are expressed in defined conditions, and that this expression depends on gene regulatory sequences. To illustrate isotype specific regulatory mechanisms, the example of 3- tubulin is presented due to its particular expression pattern as well as its importance in certain physiological phenomena and pharmacological situations.