Figure 2. A screen for rosette defect mutants in S. rosetta.
Rosette defect mutants were isolated by exposing S. rosetta haploid cells to either EMS or X-rays and then isolating clones in rosette-inducing Algoriphagus conditioned media (ACM) prior to visual screening. The use of limiting dilution to isolate clones resulted in many wells with no cells (indicated as white circles). Wells seeded with a wild-type cell (gray circles) produced a culture with abundant rosette colonies, while wells seeded with a rosette defect mutant (black circle) produced a culture with chains or single cells, but few to no chain colonies. Candidate rosette defect mutants were validated through repeated rounds of limiting dilution prior to re-screening in ACM.