Reconstitution of a cytokine receptor scaffold utilizing multiple different tyrosine motifs

Cells have intracellular signal transduction systems to control cellular fates. Cytokine receptors initiate the intracellular signaling by recruiting specific signaling molecules to a range of tyrosine-containing motifs. To specifically activate a target signaling molecule, we previously designed single-chain Fv/cytokine receptor chimeras incorporating single tyrosine motifs in the intracellular domain, and each chimeric receptor activated the corresponding signaling molecule by oligomeric antigen stimulation. However, synergistic effects of multiple signaling pathways are indispensable to regulate complex cellular fates. In this study, we extended our approach by incorporating two different motifs in the chimeric receptor, which would result in the activation of multiple signaling molecules. We used retroviral transduction to express chimeric receptors in a murine interleukin-3-dependent pro-B cell line, Ba/F3. Our results indicate that the chimeric receptors incorporating two different motifs can activate both corresponding signaling molecules by the ligand stimulation, and that the signaling intensities are influenced by the distance between two motifs. Moreover, these chimeric receptors transduced downstream signaling, which exerted synergistic effects on cellular proliferation. Our system may be used for efficiently controlling fates of various types of cells, which will be applied to tissue engineering.