Recombinant DNA approaches to study the role of the regulatory light chains (RLC) using scallop myosin as a test system.

The ability to exchange reversibly the regulatory light chains (RLCs) from scallop myosin has provided us with a test system to probe the mechanisms of regulation mediated by the RLCs from vertebrate skeletal, vertebrate smooth and molluscan myosins. The cloning and expression of these RLCs, together with domain-swapping and site-directed mutagenesis approaches, has allowed us to explore further the mechanisms involved and identify the functional importance of specific regions of the RLC molecule; for example, the presence of a high affinity metal binding site in the N-terminal domain and its interaction with the intact C-terminal domains are required for regulation.