A study of the interactions between proteins involved in chromosome segregation in Bacillus subtilis using the yeast-two-hybrid system (360G-Wellcome-206991_Z_17_Z)

During sporulation in the bacterium Bacillus subtilis, one of the sister chromosomes is translocated into the developing prespore. This mechanism is a useful model for studying chromosome segregation, a process which is vital in all organisms. The exact mechanism of chromosome segregation in sporulating B. subtilis is not fully understood. A protein complex, involving many proteins including Soj, Spo0J, MinD, MinJ, RacA, ComN and DivIVA, is known to anchor the origins of the sister chromosomes at opposite cell poles. We propose to test the direct interactions between members of this protein complex using yeast-two-hybrid assays. To begin with we will test interactions between the proteins Soj, Spo0J and MinD. Each of these are known to form dimers, and results from genetic and cell biology studies show that interactions between Soj-Spo0J and Soj-MinD are important for the anchoring of the chromosome origins to the cell poles. These latter interactions have not been shown directly and we aim to test these in this project. The project will hopefully move on to test further protein interactions in the complex, including those with RacA and ComN. Any interactions observed between these proteins will further our understanding of chromosome segregation in B. subtilis.