FIGURE 3: An abrogated Mec1-branch of the checkpoint pathway is required for Cdc13-independent cell growth.

(A) Schematic representation of the functional complementation test: 12 independent strains of cdc13Δ cells were used in this experiment. Each cap-independent cdc13Δ strain was transformed with five constructs (plasmids): pGal-MEC1, pGal-MEC3, pGal-RAD17, pGal-RAD24 or empty vector pGal-Empty as a control. Serial dilutions of cultures of the resulting strains were spotted onto YEP+ Glucose (2%) for growth control and onto YEP+ Galactose (2%) to induce the expression of indicated genes.

(B) Cells of a Cdc13-independent strain stop growing when the mutated checkpoint gene is complemented by the corresponding wild-type construct. The results shown in this figure were derived with strain MSY053 which holds a mutation in RAD24 in the genome.