Title: "It’s all about communication: how bacteria coordinate their life cycles."
Speaker: Paola Mera, Assistant Professor of Microbiology, School of Molecular & Cellular Biology, University of Illinois Urbana Champaign.
Maintaining the integrity of the chromosome is vital for the survival of bacteria. To accomplish this vital task, major cell cycle events including chromosome replication, segregation, and proper timing of cytokinesis are coordinated, temporally and spatially. Any defect that disturbs this coordination can be lethal. Although replication, segregation, and cell division have been extensively studied in bacteria, our understanding of how these processes are coordinated with each other remains limited. Using the bacterial system Caulobacter crescentus, Dr. Mera’s lab has uncovered a complex communication network that occurs between the initiator of chromosome replication (DnaA) and the initiator of chromosome segregation (ParA). For instance, their data revealed that DnaA can promote the onset of chromosome segregation independently of DnaA’s ability to initiate replication, but dependently on ParA’s activity. Similarly, ParA can promote the onset of chromosome replication independently of ParA’s ability to trigger chromosome segregation, but dependently on the presence of DnaA. Overall, Dr. Mera’s work is revealing a highly coordinated and multidirectional network that is involved in maintaining the integrity of the chromosome during the proliferation of bacteria.