Expression patterns of the <i>bst</i> genes during sporulation.

<p>Fluorescence microscopy of the eight <i>bst</i> promoter fusions to sfGFP during exponential growth (<i>t</i>_<i>0</i>), 3 hours (<i>t</i>_<i>3</i>) and 6 hours (<i>t</i>_<i>6</i>) after induction of sporulation by re-suspension. Cell membranes are stained with FM 4–64 (red). Phase images are shown to visualize cells that are late in the sporulation pathway and contain phase bright forespores. A) Micrographs of the 8 promoters fusions. GFP intensities for each strain and timepoint were adjusted individually to determine which genes were expressed under all conditions. Arrowheads show P_<i>bstB</i>-<i>sfGFP</i> and P_<i>bstE</i>-<i>sfGFP</i> expression in vegetative cells. B) Micrographs from Fig 2A with the GFP intensity at each panel adjusted to the brightest GFP (P_<i>bstB</i>-<i>sfGFP</i> at <i>t</i>₆) to illustrate the relative levels of gene expression. Phase images are shown for <i>t</i>_<i>6</i> images to allow visualization of phase bright intracellular spores at late stages of development.