Singapore, Singapore, June 06, 2018 --(PR.com)-- In a pioneering study, scientists led by Dr Wan Yue (Senior Research Scientist) and Professor Niranjan Nagarajan (Associate Director and Senior Group Leader) at the Agency for Science, Technology and Research's (A*STAR) Genome Institute of Singapore (GIS), developed the first rapid, large scale structure-probing screening method for biological sensors known as riboswitches
, or RNA sensors.
The expression of the CrcB protein is controlled by fluoride-sensing messenger RNAs named fluoride riboswitches
. The CrcB protein augments the activity of CspE to increase camphor resistance beyond the action of crcB alone, which protects the chromosome from decondensation by camphor .
Others discuss DNA self-catalyzed depurination, B12-dependent photoreceptors, engineering and in vivo applications of riboswitches
, cyclic GMP-AMP as an endogenous second messenger, antibiotics, surface-active and surfactant proteins, functionally diverse lipid-binding compartments, the evolution of membrane coating complexes, endoplasmic reticulum-plasma membrane contact sites, mitochondrial biogenesis, oxidative stress, mammalian peroxiredoxins, redox-based regulation of bacterial behavior, heme uptake and bacterial cell membranes, biological probes built from fluoresceins and rhodamines, microbial rhodopsins, and cellular electron cryotomography.
For instance, riboswitches
that are found in the 5'-untranslated region of the Salmonella typhimurium transcription, which is conserved among Gram-negative enteric bacteria, are allosterically activated by [Mn.sup.2+], rather than by [Ca.sup.2+] or [Mg.sup.2+] .
(1) Although aptamers were first described as artificial molecules, they were later found as natural components of riboswitches
that affect transcription or translation.
Bacterial genomes tend to have multiple DGCs and PDEs which suggests that cyclic-di-GMP levels are regulated through a complex signaling network integrating numerous environmental signals that control riboswitches
, transcription factors, and enzyme activities including cellulose expression.
are RNA-based regulatory elements, which control a plethora of metabolic genes in bacteria frequently found in the 5' untranslated region (UTR) of genes related to the metabolism or transport of the ligand they respond to.
"It is very likely no one would have solved the mystery of fluoride riboswitches
for several more decades, if we had not been lucky enough to receive a contaminated chemical sample spiked with fluoride." Genes associated with fluoride-sensitive riboswitches
are very widespread in biology.
Unlike other known riboswitches
, which have relatively limited functions, this one acts as a sensor for the basic molecular fuel that powers all living cells and controls many genes.
22 online issue of the journal Science Express, the researchers report that sections of RNA messages called riboswitches
-- which control the expression of genes -- detect the build-up of fluoride and activate the defenses of bacteria, including those that contribute to tooth decay.
The section on non-coding RNA includes discussions of transfer RNAs, small nucleolar RNAs, small non-coding RNAs and the mechanisms of gene silencing, RNA editing, and riboswitches
and RAN sensors.