Fig 1.

Phosphate deprivation leads to G₁ arrest. Wild-type cells were grown exponentially in synthetic complete medium. At time zero, cells were harvested and incubated either in the same medium (+PO₄²⁻) or in a medium without phosphate (−PO₄²⁻). At the indicated times, samples were collected and then subjected to several analyses: total cell number (A), DNA content (B), percentage of budding (C), and cell volume (D). (B) The DNA contents of wild-type cells incubated in a medium without a nitrogen source (−N) are shown. (C) The percentages of budding of wild-type cells carrying a centromeric plasmid with the CLN2 gene expressed from an ADH promoter are shown. Data ± standard deviations from three independent experiments are shown.