Cloning and characterization of the scallop essential and regulatory myosin light chain cDNAs.

The scallop system has several properties that make it ideal for studying the function of light chains in myosin regulation. To use a molecular genetic approach to dissect light chain function, cDNA clones of the regulatory and essential myosin light chains from the scallop (Aequipecten irradians) have been isolated from a lambda gt11 expression library. The clones were isolated using polyclonal antibodies directed against either the essential or the regulatory light chain. Four clones were isolated for the regulatory light chain, and two were isolated for the essential light chain. From these clones, the complete DNA sequences of the protein coding regions were obtained for both light chains. Both translated sequences are compared to previously published sequences of the light chains. RNA analysis shows that clones encoding both light chains hybridize to multiple RNA transcripts. Genomic DNA analysis shows that each protein is encoded by a single gene.