The association of G protein β2 subunit (Gβ2) with mitotic spindles in various mammalian cells has been demonstrated previously. Recently, we have identified the association of Gβ2 protein with microtubules (Wu et al.,  J. Cell. Biochem. 70: 552-562). In the present experiment we have demonstrated the possible functional role of Gβ2 in microtubule and mitotic spindle organization in mammalian cells. When Gβ2 antisense phosphorothioate oligonucleotides were transfected into mammalian cells, inhibition of cell proliferation with cell death after a 4-day treatment was observed. If the transfected cells were incubated for two days and their Gβ2 and microtubules were examined by Western blotting and immunofluorescence localization, marked reduction of the Gβ2 protein, fragmentation and disassembly of cytoplasmic microtubules, and disorganized mitotic spindles were found. We conclude that the Gβ2 protein is closely associated with microtubule assembly and may play a potential role in the regulation of cell proliferation and microtubule and mitotic spindle organization in mammalian cells.
- Antisense oligonucleotide transfection
- Gβ2 protein
- Microtubule assembly
- Mitotic spindle organization
- Nasopharyngeal carcinoma cells