Recombinant TGFBI and periostin support adhesion of ovarian cancer cells and stimulate Akt phosphorylation. A, Schematic representation of the domain structure of TGFBI and periostin. Both TGFBI and periostin contain conserved Fasciclin I and EMI domains, while only TGFBI contains an RGD motif. B, Purified bacterially expressed recombinant TGFBI (rTGFBI) and recombinant Periostin (rPOSTN). Coomassie brilliant blue stained SDS-PAGE of purified rTGFBI and rPOSTN and Western blot (IB) probed with specific antibodies against TGFBI and periostin. C, Bright-field images of SKOV3 adhesion to uncoated, fibronectin, rTGFBI, or rPOSTN coated tissue culture plastic. D, Results of three independent adhesion experiments were normalized to poly-L-lysine and are represented as percent of fibronectin control, *p < 0.05, **p < 0.01. E, NIH3T3 cells were replated on tissue culture wells coated with 10 μg/ml of fibronectin, rTGFBI, or rPeriostin and allowed to adhere for 30 minutes. Results of two independent experiments were normalized to poly-L-lysine and represented as percent of fibronectin control. F, Western blot analysis of NIH3T3 cell lysates following stimulation with 10 μg/ml of rTGFBI or rPeriostin in serum-free media for indicated time points. The membrane was probed with antibodies specific to the phosphorylated Serine 473 amino acid residue of Akt and pan-Akt antibodies were utilized as loading control.