THE N-TERMINAL DOMAIN OF C-MYC ASSOCIATES WITH ALPHA-TUBULIN AND MICROTUBULES IN-VIVO AND IN-VITRO

The polymerization of alpha- and beta-tubulin into microtubules result s in a complex network of microfibrils that have important structural and functional roles in all eukaryotic cells, In addition, microtubule s fan interact with a diverse family of polypeptides which are believe d to directly promote the assembly of microtubules and to modulate the ir functional activity, We have demonstrated that the c-Myc oncoprotei n interacts in vivo and in vitro with alpha-tubulin and with polymeriz ed microtubules and have defined the binding site to the N-terminal re gion within the transactivation domain of c-Myc. In addition, we have shown that c-Myc colocalizes with microtubules and remains tightly bou nd to the microtubule network after detergent extraction of intact cel ls, These findings suggest a potential role for Myc-tubulin interactio n in vivo.