SpoOA Onset of sporulation – (Stage I - II)
Spo0A during the onset of sporulation
Phosphorylated Spo0A binds to the so-called 0A box (TGNCGAA) present in the promoter sequences of 121 genes 42. High levels of phosphorylated Spo0A are required for the activation of the low-affinity promoters in front of sporulation-specific genes, such as racA, spoIIA, spoIIE and spoIIG and for the repression of genes involved in (for instance) cell division 44 and competence development 75. Accordingly, Spo0A is repeatedly described to play a key role in the initial stages of spore development such as asymmetric septum formation, engulfment and compartmentalized gene expression 33.