The level of sequestered calcium in vegetative amoebae of Dictyostelium discoideum can predict post-aggregative cell fate.

When freshly starved amoebae of Dictyostelium discoideum are stained with chlortetracycline (CTC), a cell type-specific fluorescent probe for membrane-associated calcium (CA2+) the resulting fluorescence distribution falls into two functional classes. Fluorescence-activated cell sorting shows that highly fluorescing amoebae tend to enter the prestalk pathway while those with low fluorescence tend to become prespores. In the light of previous findings, these results indicate that in addition to cell cycle phase at starvation, phenotypic variation in the level of sequestered calcium is an early correlate of cell fate.