Abstract: Objective To investigate the protein expression and subcelluar localization of novel tubulin member ε-tubulin, as well as its relationship with spindle in mouse oocytes during meiotic maturation. Methods ε-tubulin protein expression was evaluated with Western blot, its subcelluar localization and its involvement in spindle formation was detected using immunofluorescence in mouse oocytes at different meiotic stages. Results ε-tubulin protein was expressed stably and consistently throughout the meiotic progression. ε-tubulin was evenly distributed in germinal vesicle (GV) at meiotic prophase (GV stage), and immediately relocated upon germinal vesicle breakdown (GVBD), precisely colocalized with microtubule and concentrated on chromosomes until to metaphase II (MII) stage. ε-tubulin was sensitive to spindle poisons nocodazole and taxol, showing the same reaction as spindle microtubules. Conclusions Novel tubulin member ε-tubulin is stably expressed in mouse oocyte meiosis, and associates with the spindle formation and maintenance.

Key words: Key words: ε-tubulin, oocyte, meiosis, spindle