Regulatory RNA as mediator in GacA/RsmA-dependent global control of exoproduct formation in Pseudomonas fluorescens CHA0.
TLDR
A model in which GacA upregulates the expression of regulatory RNAs, such as RsmZ of strain CHA0, in response to a bacterial signal is supported, by a titration effect, which may alleviate the repressing activity of RsmA on theexpression of target mRNAs.Abstract:
In Pseudomonas fluorescens CHA0, an antagonist of root-pathogenic fungi, the GacS/GacA two-component system tightly controls the expression of antifungal secondary metabolites and exoenzymes at a posttranscriptional level, involving the RNA-binding protein and global regulator of secondary metabolism RsmA. This protein was purified from P. fluorescens, and RNA bound to it was converted to cDNA, which served as a probe to isolate the corresponding chromosomal locus, rsmZ. This gene encoded a regulatory RNA of 127 nucleotides and a truncated form lacking 35 nucleotides at the 3" end. Expression of rsmZ depended on GacA, increased with increasing population density, and was stimulated by the addition of a solvent-extractable extracellular signal produced by strain CHA0 at the end of exponential growth. This signal appeared to be unrelated to N-acyl-homoserine lactones. A conserved upstream element in the rsmZ promoter, but not the stress sigma factor RpoS, was involved in rsmZ expression. Overexpression of rsmZ effectively suppressed the negative effect of gacS and gacA mutations on target genes, i.e., hcnA (for hydrogen cyanide synthase) and aprA (for the major exoprotease). Mutational inactivation of rsmZ resulted in reduced expression of these target genes in the presence of added signal. Overexpression of rsmA had a similar, albeit stronger negative effect. These results support a model in which GacA upregulates the expression of regulatory RNAs, such as RsmZ of strain CHA0, in response to a bacterial signal. By a titration effect, RsmZ may then alleviate the repressing activity of RsmA on the expression of target mRNAs.read more
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References
More filters
Journal ArticleDOI
A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding
TL;DR: This assay is very reproducible and rapid with the dye binding process virtually complete in approximately 2 min with good color stability for 1 hr with little or no interference from cations such as sodium or potassium nor from carbohydrates such as sucrose.
Book
Molecular Cloning: A Laboratory Manual
TL;DR: Molecular Cloning has served as the foundation of technical expertise in labs worldwide for 30 years as mentioned in this paper and has been so popular, or so influential, that no other manual has been more widely used and influential.
Book
Experiments in molecular genetics
TL;DR: Molecular Genetics (Biology): An Overview | Sciencing Experimental in Molecular Genetics Experiments in molecular genetics (1972 edition) | Open ...
Journal ArticleDOI
Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen.
Charles K. Stover,X. Q. Pham,A. L. Erwin,S. D. Mizoguchi,Paul Warrener,Mark J. Hickey,Fiona S. L. Brinkman,W. O. Hufnagle,D. J. Kowalik,Lagrou Mj,R. L. Garber,L. Goltry,E. Tolentino,S. Westbrock-Wadman,Ying Yuan,L. L. Brody,S. N. Coulter,K. R. Folger,Arnold Kas,K. Larbig,R. Lim,Kelly D. Smith,David H. Spencer,Gane Ka-Shu Wong,Z. Wu,Ian T. Paulsen,Ian T. Paulsen,Jonathan Reizer,Milton H. Saier,Robert E. W. Hancock,Stephen Lory,Maynard V. Olson +31 more
TL;DR: It is proposed that the size and complexity of the P. aeruginosa genome reflect an evolutionary adaptation permitting it to thrive in diverse environments and resist the effects of a variety of antimicrobial substances.
Journal ArticleDOI
On finding all suboptimal foldings of an RNA molecule
TL;DR: The mathematical problem of determining how well defined a minimum energy folding is can now be solved and all predicted base pairs that can participate in suboptimal structures may be displayed and analyzed graphically.
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