SporeWeb

Stage 5: GerE Completion of engulfment and cortex systhesis (Stages III - IV)

GerE during engulfment

The final step in gene regulation for the formation of the mature spore is the activation of the gerE gene in the mother cell under the control of σ^K. After synthesis, another σ^K-dependent product in the form of SpoVIF is responsible for the stability and further functioning of GerE ¹⁵⁹. GerE acts both as a repressor and as an activator for a large subset of genes in the σ^K regulon ⁹⁵. Its inhibitory effect on σ^K-dependent gene expression is especially apparent, since it also represses the gene required for σ^K synthesis ¹⁵². On the other hand, over 40 genes are strongly dependent on GerE for their expression ⁹⁵. These genes are some of the latest to be activated during the sporulation process, especially those for which relief of SpoIIID repression is required ^{111, 112, 129}.