Taurine hypomodification underlies mitochondrial tRNATrp-related genetic diseases.

Escherichia coli MnmE and MnmG form a complex (EcMnmEG), generating transfer RNA (tRNA) 5-carboxymethylaminomethyluridine (cmnm5U) modification. Both cmnm5U and equivalent 5-taurinomethyluridine (τm5U, catalyzed by homologous GTPBP3 and MTO1) are found at U34 in several human mitochondrial tRNAs (hmtRNAs). Certain mitochondrial DNA (mtDNA) mutations, including m.

Experimental realization of multiple frequency photoassociation in an optical dipole trap.

The generation of cold molecules is an important topic in the field of cold atoms and molecules and has received relevant advanced research attention in ultracold chemistry, quantum computation, and quantum metrology. With a high atomic phase space density, optical dipole traps have been widely used to prepare, trap, and study cold molecules. In this work, Rb2 molecules were photoassociated in a magneto-optical trap to obtain a precise rovibrational spectrum, which provided accurate numerical references for the realization of multiple frequency photoassociation.

ADATs: roles in tRNA editing and relevance to disease.

Transfer RNAs (tRNAs) play central roles in protein biosynthesis. Post-transcriptional RNA modifications affect tRNA function and stability. Among these modifications, RNA editing is a widespread RNA modification in three domains of life.

Eukaryotic AlaX provides multiple checkpoints for quality and quantity of aminoacyl-tRNAs in translation.

Translational fidelity relies critically on correct aminoacyl-tRNA supply. The trans-editing factor AlaX predominantly hydrolyzes Ser-tRNAAla, functioning as a third sieve of alanyl-tRNA synthetase (AlaRS). Despite extensive studies in bacteria and archaea, the mechanism of trans-editing in mammals remains largely unknown.

Activity reconstitution of Kre33 and Tan1 reveals a molecular ruler mechanism in eukaryotic tRNA acetylation.

RNA acetylation is a universal post-transcriptional modification that occurs in various RNAs. Transfer RNA (tRNA) acetylation is found at position 34 (ac4C34) in bacterial tRNAMet and position 12 (ac4C12) in eukaryotic tRNASer and tRNALeu. The biochemical mechanism, structural basis and functional significance of ac4C34 are well understood; however, despite being discovered in the 1960s and identification of Kre33/NAT10 and Tan1/THUMPD1 as modifying apparatuses, ac4C12 modification activity has never been reconstituted for nearly six decades.

Pathophysiology of human mitochondrial tRNA metabolism.

Mitochondria play multiple critical roles in cellular activity. In particular, mitochondrial translation is pivotal in the regulation of mitochondrial and cellular homeostasis. In this forum article, we discuss human mitochondrial tRNA metabolism and highlight its tight connection with various mitochondrial diseases caused by mutations in aminoacyl-tRNA synthetases, tRNAs, and tRNA-modifying enzymes.

Transcriptome analysis unveils the mechanisms of lipid metabolism response to grayanotoxin I stress in .

Background: (tobacco caterpillar, ) is a pest of great economic importance due to being a polyphagous and world-distributed agricultural pest. However, agricultural practices involving chemical pesticides have caused resistance, resurgence, and residue problems, highlighting the need for new, environmentally friendly methods to control the spread of .

Aim: This study aimed to investigate the gut poisoning of grayanotoxin I, an active compound found in , on , and to explore the underlying mechanisms of these effects.

Mammalian trans-editing factor ProX is able to deacylate tRNA mischarged with alanine.

The precise coupling of tRNAs with their cognate amino acids, known as tRNA aminoacylation, is a stringently regulated process that governs translation fidelity. To ensure fidelity, organisms deploy multiple layers of editing mechanisms to correct mischarged tRNAs. Prior investigations have unveiled the propensity of eukaryotic AlaRS to erroneously attach alanine onto tRNA and tRNA featuring the G4:U69 base pair.

Mammalian mitochondrial translation infidelity leads to oxidative stress-induced cell cycle arrest and cardiomyopathy.

Proofreading (editing) of mischarged tRNAs by cytoplasmic aminoacyl-tRNA synthetases (aaRSs), whose impairment causes neurodegeneration and cardiac diseases, is of high significance for protein homeostasis. However, whether mitochondrial translation needs fidelity and the significance of editing by mitochondrial aaRSs have been unclear. Here, we show that mammalian cells critically depended on the editing of mitochondrial threonyl-tRNA synthetase (mtThrRS, encoded by ), disruption of which accumulated Ser-tRNA and generated a large abundance of Thr-to-Ser misincorporated peptides in vivo.

Mitochondrial RNA mC methyltransferase METTL8 relies on an isoform-specific N-terminal extension and modifies multiple heterogenous tRNAs.

Methyltransferase-like 8 (METTL8) encodes a mitochondria-localized METTL8-Iso1 and a nucleolus-distributed METTL8-Iso4 isoform, which differ only in their N-terminal extension (N-extension), by mRNA alternative splicing. METTL8-Iso1 generates 3-methylcytidine at position 32 (mC32) of mitochondrial tRNA and tRNA(UCN). Whether METTL8-Iso4 is an active mC32 methyltransferase and the role of the N-extension in mitochondrial tRNA mC32 formation remain unclear.

An advanced treatment process for 3-high wastewater discharged from crude oil storage tanks.

The wastewater discharged from crude oil storage tanks (WCOST) contains high concentrations of salt and metal iron ions, and high chemical oxygen demand (COD). It belongs to "3-high" wastewater, which is difficult for purification. In this study, WCOST treatments were comparatively investigated via an advanced pretreatment and the traditional coagulation-microfiltration (CMF) processes.

nASAP: A Nascent RNA Profiling Data Analysis Platform.

Although nascent RNA profiling data are widely used in transcriptional regulation studies, the development and standardization of data processing pipeline lags far behind RNA-seq. We are filling this gap by establishing the nASAP web server (https://grobase.top/nasap/) to provide practical quality evaluation and comprehensive analysis of nascent RNA datasets.

LncRNA FAS-AS1 upregulated by its genetic variation rs6586163 promotes cell apoptosis in nasopharyngeal carcinoma through regulating mitochondria function and Fas splicing.

Nasopharyngeal carcinoma (NPC) is a common head and neck malignant with a high incidence in Southern China. Genetic aberrations play a vital role in the pathogenesis, progression and prognosis of NPC. In the present study, we elucidated the underlying mechanism of FAS-AS1 and its genetic variation rs6586163 in NPC.

Continuously and widely tunable frequency-stabilized laser based on an optical frequency comb.

Continuously and widely tunable lasers, actively stabilized on a frequency reference, are broadly employed in atomic, molecular, and optical (AMO) physics. The frequency-stabilized optical frequency comb (OFC) provides a novel optical frequency reference, with a broadband spectrum that meets the requirement of laser frequency stabilization. Therefore, we demonstrate a frequency-stabilized and precisely tunable laser system based on it.

RNA granule-clustered mitochondrial aminoacyl-tRNA synthetases form multiple complexes with the potential to fine-tune tRNA aminoacylation.

Mitochondrial RNA metabolism is suggested to occur in identified compartmentalized foci, i.e. mitochondrial RNA granules (MRGs).

Selective degradation of tRNASer(AGY) is the primary driver for mitochondrial seryl-tRNA synthetase-related disease.

Mitochondrial translation is of high significance for cellular energy homeostasis. Aminoacyl-tRNA synthetases (aaRSs) are crucial translational components. Mitochondrial aaRS variants cause various human diseases.