Abi1 isoform-specific regulation of Rac1 activation and interaction.

A. Isoform 2 expressing cell line exhibits lower levels of activated Rac1 but exhibits greater Rac1 activation in response to PDGF. Serum starved and PDGF-induced Rac1 activity was evaluated by luminescence assay (Materials and Methods); PDGF was at 100 ng/ml. Measurements were performed in triplicate, error bars represent ± s.e.m., n = 4. B. PDGF-induced Alexa Fluor 647 uptake is enhanced in Abi1 isoform expressing cell lines. Cellular accumulation of Alexa Fluor 647 in LNCaP cell lines was evaluated by flow cytometry in serum starved or PDGF (100 ng/ml) treated cells following a 2-hour incubation with the dye. Mock, mock transfected cell line; Iso-2.1, isoform 2 expressing cell line; Iso-3.1, isoform 3 expressing cell line. Measurements were performed in triplicate, n = 3, error bars ± s.e.m.