title: Post-transcriptionally generated cell heterogeneity regulates biofilm formation in Bacillus subtilis.
abstract: Bacillus subtilis forms biofilms in appropriate environments by producing extracellular matrices. Genes required for matrix formation, for example tapA, are regulated by the SinI/SinR/SlrR system. SinR is the repressor for tapA. SinI and SlrR inhibit DNA-binding of SinR. sinI and sinR constitute two-gene operon, and sinR has its own promoter. During biofilm formation, a portion of the population differentiates into matrix-producing cells. This is thought to be caused by Spo0A-dependent, heterogeneous expression of the PsinI promoter, whereas the PsinR promoter is expressed homogeneously. However, we observed that at its original locus, overall sinI transcription was almost homogeneous, because upstream read-through transcription from PyqHG would overcome expression of PsinI. When we used translational sinI-gfp and sinR-mCherry reporters at their original loci, their fluorescence distribution patterns in the cell population were clearly bimodal. This bimodal expression might be caused by cell-to-cell variations of mRNA stability. This study shows that the post-transcriptionally regulated bimodal expression of SinI and SinR is important for bacterial cell-fate determination.
authors.affiliation: Institute of Oceanic Research and Development, Tokai University, 3-20-1 Orido-Shimizu, Shizuoka, 424-8610, Japan.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Ogura
mesh_terms: D001412:Bacillus subtilis / Q000166:cytology / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms; D049452:Green Fluorescent Proteins / Q000235:genetics; D008164:Luminescent Proteins / Q000378:metabolism; D009154:Mutation; D012323:RNA Processing, Post-Transcriptional; D012260:Ribonucleases / Q000378:metabolism; D000097573:Red Fluorescent Protein
chemical_list: D001426:Bacterial Proteins; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D012260:Ribonucleases; D000097573:Red Fluorescent Protein; C066497:DegU protein, Bacteria; C076733:FlaD protein, Bacteria