Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The Thermus thermophilus DEAD-box protein Hera is a general RNA chaperone and plays a key role in tRNA metabolism

ABSTRACT: RNA helicases catalyze the ATP-dependent destabilization of RNA duplexes. DEAD-box helicases share a helicase core that mediates ATP binding and hydrolysis, RNA binding and unwinding. Most members of this family contain domains flanking the core that can confer RNA substrate specificity and guide the helicase to a specific RNA. However, the in vivo RNA substrates of most helicase are currently not defined. The DEAD-box helicase Hera from Thermus thermophilus contains a helicase core, followed by a dimerization domain (DD) and an RNA binding domain (RBD) that folds into an RNA recognition motif (RRM). The RRM mediates high affinity binding to an RNA hairpin, and an adjacent duplex is then unwound by the helicase core. Hera is a cold-shock protein, and has been suggested to act as an RNA chaperone under cold-shock conditions. Using immunoprecipitation of Hera-RNA complexes and RNA-Seq, we show that Hera binds to a large fraction of T. thermophilus RNAs under normal-growth and cold-shock conditions without a strong sequence preference, in agreement with a structure-specific recognition of RNAs and a general function in RNA metabolism. Under cold-shock conditions, Hera is recruited to RNAs with high propensities to form stable secondary structures. We show that selected RNAs identified, including a set of tRNAs, bind to Hera in vitro, and activate the Hera helicase core. Gene ontology analysis reveals an enrichment of genes related to translation, including mRNAs of ribosomal proteins, tRNAs, tRNA ligases, and tRNA-modifying enzymes, consistent with a key role of Hera in ribosome assembly and tRNA metabolism.

ORGANISM(S): Thermus thermophilus HB27

PROVIDER: GSE135435 | GEO | 2020/10/22

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Identification of RNA helicases that mediate processing of tRNAs into distinct tRNA fragments by LC-MS/MS.

Project description:Specific environmental insults cause the limited fragmentation of transfer RNAs (tRNAs) into tRNA-derived small RNAs (tsRNAs), which have been implicated in a wide range of biological processes. tRNA fragmentation results from endonucleolytic activities targeting single-stranded tRNA regions. However, how a tRNA with a single hydrolyzed phosphodiester bond in the anticodon loop (‘nicked’ tRNA) gives rise to distinct tsRNAs remains poorly understood. By utilizing biochemical fractionation of tsRNA-containing ribonucleoprotein complexes (RNPs) coupled with LC-MS/MS, we identified several RNA helicase enzymes that represent putative tRNA/tsRNA processing enzymes. Furthermore, a combination of biochemical and computational approaches revealed that specific RNA helicases indeed bind specific tRNAs with high affinity, as well as process nicked tRNAs into individual tsRNAs. In summary, these findings reveal that tRNA-derived duplexes can be substrates of well-known RNA helicases, thereby expanding their potential for cellular function to the creation of individual tsRNAs during the cellular stress response.

2023-01-09 | PXD029869 | Pride

Hydrogen-deuterium exchange mass spectrometry of wt Mtr4 with various RNA substrates

Project description:Mtr4 is a eukaryotic RNA helicase required for RNA decay by the nuclear exosome. Previous studies have shown how RNA enroute to the exosome threads through the highly conserved helicase core of Mtr4. Mtr4 also contains an arch domain, although details of potential interactions between the arch and RNA have been elusive. To understand the interaction of Saccharomyces cerevisiae Mtr4 with various RNAs, we have characterized RNA binding in solution using hydrogen-deuterium exchange mass spectrometry, and affinity and unwinding assays. We have identified RNA interactions within the helicase core that are consistent with existing structures and do not vary between tRNA, single-stranded RNA, and double-stranded RNA constructs. We have also identified novel RNA interactions with a region of the arch known as the fist or KOW. These interactions are important for RNA unwinding and vary in strength depending on RNA structure and length. They account for Mtr4 discrimination between different RNAs. These interactions further drive Mtr4 to adopt a closed conformation characterized by reduced dynamics of the arch arm and intra-domain contacts between the fist and helicase core.

2022-03-07 | PXD031962 | Pride

Small RNA sequencing of in vitro Angiogenin-hydrolyzed tRNAs

Project description:Specific environmental insults cause the limited fragmentation of transfer RNAs (tRNAs) into tRNA-derived small RNAs (tsRNAs), which have been implicated in a wide range of biological processes. tRNA fragmentation results from endonucleolytic activities targeting single-stranded tRNA regions. However, how a tRNA with a single hydrolyzed phosphodiester bond in the anticodon loop (‘nicked’ tRNA) gives rise to distinct tsRNAs remains poorly understood. After identifying RNA helicases that were able to unwind ‘nicked’ tRNAs in vitro, the specificity of one of those enzymes, DDX3X, was determined by RNA helicase assays on tRNAs, which had been subjected to recombinant Angiogenin. Both in vivo ‘nicked’ tRNAs, DDX3X-unwound ‘nicked’ tRNAs as well as heat-denatured ‘nicked’ tRNAs were subjected to small RNA sequencing.

2022-04-05 | GSE187021 | GEO

Cooperation of GRSF1 and the mitochondrial degradosome (hSuv3-PNPase complex) in degradation of mitochondrial RNA

Project description:Vertebrate mitochondrial genomes show extraordinary GC skew which results in the synthesis of RNAs prone to form G-quadruplexes (G4). Such RNAs, although mostly non-coding, are transcribed at high rate and swiftly degraded by an unknown mechanism. Comprehensive proteomic and transcriptomic approaches revealed that quasi-RRM protein GRSF1 together with the mitochondrial degradosome composed of RNA helicase hSuv3 and PNPase control the levels of G4 containing RNAs in mitochondria. When this machinery is inactivated non-coding mtRNAs are upregulated and novel, previously undescribed transcript, which we named tRNA-like, strongly accumulates. In vitro reconstitution experiments showed that GRSF is responsible for G4 RNA melting essential for degradosome-mediated decay.

2018-06-17 | GSE106368 | GEO

Influence of cold shock on total mRNA expression profile during harvesting Thermus thermophilus HB8 cells.

2010-10-15 | GSE19723 | GEO

The cold shock response of Bacillus subtilis analyzed by RNA-sequencing: YplP regulates pyruvate transport at low temperatures

Project description:The cold shock response of B. subtilis was defined after 0.5 hr and 2 hr cold shock using RNA sequencing. We identified novel RNAs (including non-coding RNAs) that play a role during growth at low temperatures. Deletion of the cold induced protein YplP results in a cold sensitive phenotype, and a comparative RNA sequencing analysis suggests that YplP induces pftAB expression after prolonged incubation at low temperatures, thereby optimizing pyruvate transport under cold shock conditions.

2018-03-12 | GSE111577 | GEO

Influence of cold shock on total mRNA expression profile during harvesting Thermus thermophilus HB8 cells.

Project description:In order to investigate the influence of the cold shock during harvesting the cells, we compare the expression profile of mRNA between in T. thermophilus HB8 cells harvested after arrested the growth on ice and in those harvested after addition of cold ethanol. Three wild-type strain of T. thermophilus HB8 were pre-cultured at 70Â°C for 16 hours in 3 mL of TT medium containing 0.8% polypeptone, 0.4% yeast extract, 0.2% NaCl, 0.4 mM CaCl2, and 0.4 mM MgCl2, which was adjusted to pH 7.2 with NaOH. The cells (2 mL) were inoculated into 1000 mL of same medium and then cultivated at 70Â°C for 8 hours (A600 value being ~2.57). For normal cells (harvested after arrested the growth on ice), 15 mL of culture medium was centrifuged 4270G for 5 min at 4Â°C. For cold-shock avoided cells (harvested after addition of cold ethanol), 15 mL of culture medium was cooled down immediately by addition of the same volume of ethanol which pre-cooled to -80Â°C, and then centrifuged in same way as normal cells. Then crude RNA was extracted from each sample.

2010-10-15 | E-GEOD-19723 | biostudies-arrayexpress

Alteration of DNA supercoiling serves as a trigger of short-term cold shock repressed genes of E. coli

Project description:Cold shock adaptability is a key survival skill of gut bacteria of warm-blooded animals. Escherichia coli cold shock responses are controlled by a complex multi-gene, timely-ordered transcriptional program. We investigated its underlying mechanisms. Having identified short-term, cold shock repressed genes, we show that their responsiveness is unrelated to their transcription factors or global regulators, while their single-cell protein numbers’ variability increases after cold shock. We hypothesized that some cold shock repressed genes could be triggered by high propensity for transcription locking due to changes in DNA supercoiling (likely due to DNA relaxation caused by an overall reduction in negative supercoiling). Concomitantly, we found that nearly half of cold shock repressed genes are also highly responsive to gyrase inhibition (albeit most genes responsive to gyrase inhibition are not cold shock responsive). Further, their response strengths to cold shock and gyrase inhibition correlate. Meanwhile, under cold shock, nucleoid density increases, and gyrases and nucleoid become more colocalized. Moreover, the cellular energy decreases, which may hinder positive supercoils resolution. Overall, we conclude that sensitivity to diminished negative supercoiling is a core feature of E. coli’s short-term, cold shock transcriptional program, and could be used to regulate the temperature sensitivity of synthetic circuits.

2022-07-20 | GSE194037 | GEO

Structural basis of RNA-induced autoregulation of the DExH-type RNA helicase maleless

Project description:RNA unwinding by DExH-type helicases underlies most RNA metabolism and function. It remains unresolved if and how the basic unwinding reaction of helicases is regulated by auxiliary domains. We explored the interplay between the RecA and auxiliary domains of the RNA helicase maleless (MLE) from Drosophila, using a suite of structural and functional studies. We discovered that MLE exists in a dsRNA bound open conformation and the auxiliary dsRBD2 domain aligns the substrate RNA with the accessible helicase tunnel. In an ATP-dependent manner, dsRBD2 associates with the helicase module, leading to tunnel closure around ssRNA. Furthermore, our structures provide a rationale for blunt ended dsRNA unwinding and 3’-5’ translocation by MLE. Structure-based MLE mutations confirm the functional relevance of our model for RNA unwinding. Our findings contribute to our understanding of fundamental mechanics of auxiliary domains in DExH helicase MLE which serves as model for its human ortholog and potentially therapeutic target, DHX9/RHA.

2023-11-27 | PXD045725 | Pride

Substrate discrimination and quality control require each catalytic activity of TRAMP and the nuclear RNA exosome

Project description:Abstract: Quality control requires discrimination between functional and aberrant species to selectively target substrates for destruction. Nuclear RNA quality control in Saccharomyces cerevisiae includes the TRAMP complex that marks RNA for decay via polyadenylation and helicase-dependent 3′ to 5′ degradation by the RNA exosome. Using reconstitution biochemistry we show that polyadenylation and helicase activities of TRAMP cooperate with processive and distributive exoribonuclease activities of the nuclear RNA exosome to selectively target and degrade an unmodified tRNA while leaving native tRNA intact. Inactivation of the distributive exoribonuclease activity of Rrp6 results in loss of substrate discrimination, leading to degradation of all RNAs. These data suggest that the activities of the Mtr4 helicase and Rrp6 exoribonuclease endow the TRAMP-RNA exosome complex with the ability to protect stable RNA while degrading defective RNA species. Rrp6 and its 3′-5′ exonuclease activity have previously been shown to contribute to quality control and processing of various types of nuclear RNAs. Our sequencing analysis further confirms that Rrp6 contributes to this process.

2021-03-18 | GSE160368 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data