Abstract: The present disclosure provides a conjugate comprising: a) an affinity agent that specifically binds a target ligand-binding polypeptide; and b) a photoisomerizable regulator comprising: i) a photoisomerizable moiety; and ii) a ligand that binds to the target ligand-binding polypeptide. The present disclosure provides cells comprising a conjugate of the present disclosure. The present disclosure provides methods of using a conjugate of the present disclosure to modulate activity of a target polypeptide, and to modulate activity of a target cell or cell population.