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Xu, W., Huang, J., Lin, R., Shi, J. & Cohen, S. N Regulation of morphological differentiation in S. coelicolor by RNase III (AbsB) cleavage of mRNA encoding the AdpA transcription factor. Mol. Microbiol. 75, 781-791

Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
Molecular Microbiology (Impact Factor: 4.42). 02/2010; 75(3):781-91. DOI: 10.1111/j.1365-2958.2009.07023.x
Source: PubMed

ABSTRACT

RNase III family enzymes, which are perhaps the most widely conserved of all ribonucleases, are known primarily for their role in the processing and maturation of small RNAs. The RNase III gene of Streptomyces coelicolor, which was discovered initially as a global regulator of antibiotic production in this developmentally complex bacterial species and named absB (antibiotic biosynthesis gene B), has subsequently also been found to modulate the cellular abundance of multiple messenger RNAs implicated in morphological differentiation. We report here that regulation of differentiation-related mRNAs by the S. coelicolor AbsB/RNase III enzyme occurs largely by ribonucleolytic cleavage of transcripts encoding the pleiotropic transcription factor, AdpA, and that AdpA and AbsB participate in a novel feedback-control loop that reciprocally regulates the cellular levels of both proteins. Our results reveal a previously unsuspected mechanism for global ribonuclease-mediated control of gene expression in streptomycetes.

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Available from: Jing Shi, Jan 14, 2015
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    • "morphological development is mediated by RNase III cleavage of mRNA encoding the AdpA transcription factor (Xu et al., 2010). AdpA plays a key role in the regulation of both morphological differentiation and secondary metabolite biosynthesis (Xu et al., 2010). Some RNase mutants show defects in cell morphology of Escherichia coli and Bacillus subtilis. "
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    • "Relief of ScbR2 binding to the cpkO promoter has also been observed by adding Act ( and Red , although the data for this ambiguous ) , and it is pos - tulated that this antibiotic may be a ScbR2 ligand , indicating another pos - sible mechanism of regulatory cross talk between different antibiotic biosynthetic pathways ( Xu , Huang , et al . , 2010 ) . The γ - butyrolactones represent important small autoregulatory molecules controlling antibiotic biosynthesis . Production of Mmy , encoded by the mmy gene cluster on the plasmid SCP1 , is controlled in a similar manner by similar , but different , chemical entities , the MMF furans ( Corre et al . , 2008 ) , see also Section 4 . 1 "
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    • "In S. coelicolor, BldD represses adpA expression [21]. At the translational level, a feedback-control loop regulates levels of AdpA and AbsB (a RNAse III) in S. coelicolor[22,23]. A positive feedback loop between AdpA and BldA, the only tRNA able to read the UUA codon present in all adpA mRNA, has been demonstrated in S. griseus[22,23]. "
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