Figure 1. Chemically Self-Assembled Nanorings (CSANs).
Bivalent DHFR2 proteins fused to a targeting domain are spontaneously oligomerized into CSANs via the chemical dimerizer, bisMTX. In this work, a fibronectin domain with engineered specificity for epithelial cell adhesion molecule (EpCAM)46 was fused, enabling the formation of EpCAM-targeted CSANs. While not drawn to scale, the CSAN scaffold as a whole is 19 ± 5 nm in diameter, as depicted by the rough scale bar.43