JWA protein binds to α-tubulin in PC12 cells

Our previous study elucidated that JWA protein was a newly identified microtubule-associated protein (MAP), which combined to and co-localized with beta-tubulin. In the present study, we designed a series of experiments to explore if any interactions between JWA protein and (alpha-tubulin existed and how JWA prot, in would functionally link to a-tubulin, especially in cell mitosis. Results of co-immunoprecipitation, gene transfection and immunofluorescence microscopy from PC12 and HEK293 cells provided strong evidence for a linkage between JWA protein and alpha-tubulin. Our data showed that JWA protein bound to (alpha-tubulin stably no matter whether a-tubulin was polymerized or not. In addition, by using antisense oligonucleotides, cell cycle blocking agents and hypothermia disposal techniques, we also found the interaction between JWA protein and a-tubulin. The further analysis using flow cytometry and confocal microscopy showed that both proteins co-existed in PC12 cells and were independent on the cell cycle. In conclusion, JWA protein is a newly identified microtubule-associated protein, binds to a-tubulin, and probably plays an important role in regulation of microtubular stability.