Complex sentence: Initally, Riggs continued his lac repressor work, examining gene regulation in bacteria with Richard E. Dickerson, John Rosenberg, and Keiichi Itakura.
Split into simpler sentences: Initally, Riggs continued his lac repressor work, examining gene regulation in bacteria. Riggs worked with Richard E. Dickerson, John Rosenberg, and Keiichi Itakura.