YB-1 promotes microtubule assembly in vitro through interaction with tubulin and microtubules

摘要

Background: YB-1 is a major regulator of gene expression in eukaryotic cells. In addition to itsrole in transcription, YB-1 plays a key role in translation and stabilization of mRNAs.Results: We show here that YB-1 interacts with tubulin and microtubules and stimulatesmicrotubule assembly in vitro. High resolution imaging via electron and atomic force microscopyrevealed that microtubules assembled in the presence of YB-1 exhibited a normal single wallultrastructure and indicated that YB-1 most probably coats the outer microtubule wall.Furthermore, we found that YB-1 also promotes the assembly of MAPs-tubulin and subtilisin-treated tubulin. Finally, we demonstrated that tubulin interferes with RNA:YB-1 complexes.Conclusion: These results suggest that YB-1 may regulate microtubule assembly in vivo and thatits interaction with tubulin may contribute to the control of mRNA translation.