The "pro" sequence of the sporulation-specific sigma transcription factor sigma(E) directs it to the mother cell side of the sporulation septum

• Published in: Journal of bacteriology Vol. 181; no. 19; pp. 6171 - 6175
• Main Authors: Ju, J, Haldenwang, W G
• Format: Journal Article
• Language: English
• Published: United States 01.10.1999
• Subjects: Bacillus subtilis - physiology; Bacterial Proteins - metabolism; Biological Transport; Cell Compartmentation; Endopeptidases - metabolism; Green Fluorescent Proteins; Luminescent Proteins - genetics; Luminescent Proteins - metabolism; Membrane Proteins - metabolism; Peptide Hydrolases; Protein Precursors - metabolism; Protein Processing, Post-Translational; Protein Sorting Signals - metabolism; Recombinant Fusion Proteins - metabolism; Sigma Factor - genetics; Sigma Factor - metabolism; Spores, Bacterial; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 0021-9193
• DOI: 10.1128/jb.181.19.6171-6175.1999

sigma(E), a mother cell-specific transcription factor of sporulating Bacillus subtilis, is derived from an inactive precursor protein (pro-sigma(E)). Activation of sigma(E) occurs when a sporulation-specific protease (SpoIIGA) cleaves 27 amino acids from the pro-sigma(E) amino terminus. This reaction is believed to take place at the mother cell-forespore septum. Using a chimera of pro-sigma(E) and green fluorescent protein (GFP) to visualize the intracellular location of pro-sigma(E) by fluorescence microscopy, and lysozyme treatment to separate the mother cell and forespore compartments, we determined that the pro-sigma(E)::GFP signal, localized to the forespore septum prior to lysozyme treatment, is restricted to the mother cell compartment after treatment. Thus, pro-sigma(E)::GFP had been sequestered to the mother cell side of the septum. This segregation of pro-sigma(E)::GFP, and presumably pro-sigma(E), to the mother cell is likely to be the reason why sigma(E) activity is restricted to that compartment.