AKT-dependent nuclear localization of EPRS1 activates PARP1 in breast cancer cells.

Glutamyl-prolyl-tRNA synthetase (EPRS1) is a bifunctional aminoacyl-tRNA-synthetase (aaRS) essential for decoding the genetic code. EPRS1 resides, with seven other aaRSs and three noncatalytic proteins, in the cytoplasmic multi-tRNA synthetase complex (MSC). Multiple MSC-resident aaRSs, including EPRS1, exhibit stimulus-dependent release from the MSC to perform noncanonical activities distinct from their primary function in protein synthesis.

Cell surface CD55 traffics to the nucleus leading to cisplatin resistance and stemness by inducing PRC2 and H3K27 trimethylation on chromatin in ovarian cancer.

Background: Platinum resistance is the primary cause of poor survival in ovarian cancer (OC) patients. Targeted therapies and biomarkers of chemoresistance are critical for the treatment of OC patients. Our previous studies identified cell surface CD55, a member of the complement regulatory proteins, drives chemoresistance and maintenance of cancer stem cells (CSCs).

Homozygous EPRS1 missense variant causing hypomyelinating leukodystrophy-15 alters variant-distal mRNA mA site accessibility.

Hypomyelinating leukodystrophy (HLD) is an autosomal recessive disorder characterized by defective central nervous system myelination. Exome sequencing of two siblings with severe cognitive and motor impairment and progressive hypomyelination characteristic of HLD revealed homozygosity for a missense single-nucleotide variant (SNV) in EPRS1 (c.4444 C > A; p.

Host-like RNA Elements Regulate Virus Translation.

Viruses are obligate, intracellular parasites that co-opt host cell machineries for propagation. Critical among these machineries are those that translate RNA into protein and their mechanisms of control. Most regulatory mechanisms effectuate their activity by targeting sequence or structural features at the RNA termini, i.

Homeostatic iron regulatory protein drives glioblastoma growth via tumor cell-intrinsic and sex-specific responses.

Background: Glioblastoma (GBM) displays alterations in iron that drive proliferation and tumor growth. Iron regulation is complex and involves many regulatory mechanisms, including the homeostatic iron regulator () gene, which encodes the homeostatic iron regulatory protein. While is upregulated in GBM and correlates with poor survival outcomes, the function of HFE in GBM remains unclear.

Aminoacyl-tRNA synthetase interactions in SARS-CoV-2 infection.

Aminoacyl-tRNA synthetases (aaRSs) are ancient enzymes that serve a foundational role in the efficient and accurate translation of genetic information from messenger RNA to proteins. These proteins play critical, non-canonical functions in a multitude of cellular processes. Multiple viruses are known to hijack the functions of aaRSs for proviral outcomes, while cells modify antiviral responses through non-canonical functions of certain synthetases.

Translational control of murine adiponectin expression by an upstream open reading frame element.

Adiponectin, an adipocyte-specific secretory protein encoded by the gene has a causal role in insulin resistance. Anti-diabetic drugs increase plasma adiponectin by a poorly understood, post-transcriptional mechanism enhancing insulin sensitivity. Deletion analysis of a reporter bearing the mouse mRNA 5'-leader identified an inhibitory -regulatory sequence.

A viral pan-end RNA element and host complex define a SARS-CoV-2 regulon.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, generates multiple protein-coding, subgenomic RNAs (sgRNAs) from a longer genomic RNA, all bearing identical termini with poorly understood roles in regulating viral gene expression. Insulin and interferon-gamma, two host-derived, stress-related agents, and virus spike protein, induce binding of glutamyl-prolyl-tRNA synthetase (EPRS1), within an unconventional, tetra-aminoacyl-tRNA synthetase complex, to the sgRNA 3'-end thereby enhancing sgRNA expression. We identify an EPRS1-binding sarbecoviral pan-end activating RNA (SPEAR) element in the 3'-end of viral RNAs driving agonist-induction.

Benefits of co-translational complex assembly for cellular fitness.

Complexes of two or more proteins form many, if not most, of the intracellular "machines" that execute physical and chemical work, and transmit information. Complexes can form from stochastic post-translational interactions of fully formed proteins, but recent attention has shifted to co-translational interactions in which the most common mechanism involves binding of a mature constituent to an incomplete polypeptide emerging from a translating ribosome. Studies in yeast have revealed co-translational interactions during formation of multiple major complexes, and together with recent mammalian cell studies, suggest widespread utilization of the mechanism.

, genome-wide profiling of endogenously tagged chromatin-binding proteins with spatial and temporal resolution using NanoDam in .

NanoDam is a technique for genome-wide profiling of the binding targets of any endogenously tagged chromatin-binding protein , without the need for antibodies, crosslinking, or immunoprecipitation. Here, we explain the procedure for NanoDam experiments in , starting from a genetic cross, to the generation of sequencing libraries and, finally, bioinformatic analysis. This protocol can be readily adapted for use in other model systems after simple modifications.

Glutamyl-prolyl-tRNA synthetase 1 coordinates early endosomal anti-inflammatory AKT signaling.

The AKT signaling pathway plays critical roles in the resolution of inflammation. However, the underlying mechanisms of anti-inflammatory regulation and signal coordination remain unclear. Here, we report that anti-inflammatory AKT signaling is coordinated by glutamyl-prolyl-tRNA synthetase 1 (EPRS1).

Analysis of nested alternate open reading frames and their encoded proteins.

Transcriptional and post-transcriptional mechanisms diversify the proteome beyond gene number, while maintaining a sequence relationship between original and altered proteins. A new mechanism breaks this paradigm, generating novel proteins by translating alternative open reading frames (Alt-ORFs) within canonical host mRNAs. Uniquely, 'alt-proteins' lack sequence homology with host ORF-derived proteins.

The Drosophila homologue of CTIP1 (Bcl11a) and CTIP2 (Bcl11b) regulates neural stem cell temporal patterning.

In the developing nervous system, neural stem cells (NSCs) use temporal patterning to generate a wide variety of different neuronal subtypes. In Drosophila, the temporal transcription factors, Hunchback, Kruppel, Pdm and Castor, are sequentially expressed by NSCs to regulate temporal identity during neurogenesis. Here, we identify a new temporal transcription factor that regulates the transition from the Pdm to Castor temporal windows.

TRIM-NHL protein, NHL-2, modulates cell fate choices in the C. elegans germ line.

Many tissues contain multipotent stem cells that are critical for maintaining tissue function. In Caenorhabditis elegans, germline stem cells allow gamete production to continue in adulthood. In the gonad, GLP-1/Notch signaling from the distal tip cell niche to neighboring germ cells activates a complex regulatory network to maintain a stem cell population.

Multimodal cotranslational interactions direct assembly of the human multi-tRNA synthetase complex.

Amino acid ligation to cognate transfer RNAs (tRNAs) is catalyzed by aminoacyl-tRNA synthetases (aaRSs)-essential interpreters of the genetic code during translation. Mammalian cells harbor 20 cytoplasmic aaRSs, out of which 9 (in 8 proteins), with 3 non-aaRS proteins, AIMPs 1 to 3, form the ∼1.25-MDa multi-tRNA synthetase complex (MSC).

NanoDam identifies Homeobrain (ARX) and Scarecrow (NKX2.1) as conserved temporal factors in the Drosophila central brain and visual system.

Temporal patterning of neural progenitors is an evolutionarily conserved strategy for generating neuronal diversity. Type II neural stem cells in the Drosophila central brain produce transit-amplifying intermediate neural progenitors (INPs) that exhibit temporal patterning. However, the known temporal factors cannot account for the neuronal diversity in the adult brain.

IL-17-induced HIF1α drives resistance to anti-PD-L1 via fibroblast-mediated immune exclusion.

Increasing evidence suggests that intratumoral inflammation has an outsized influence on antitumor immunity. Here, we report that IL-17, a proinflammatory cytokine widely associated with poor prognosis in solid tumors, drives the therapeutic failure of anti-PD-L1. By timing the deletion of IL-17 signaling specifically in cancer-associated fibroblasts (CAFs) in late-stage tumors, we show that IL-17 signaling drives immune exclusion by activating a collagen deposition program in murine models of cutaneous squamous cell carcinoma (cSCC).

An optimized protocol for and structural determination of the multi-tRNA synthetase complex by cross-linking mass spectrometry.

Despite recent advances in structural determination of individual proteins, elucidating the 3-dimensional architecture of large, multiprotein complexes remains challenging, partly because of issues related to structural integrity during purification. Here, we describe a protocol to determine the 3-dimensional architecture of the 11-constituent, multi-tRNA synthetase complex (MSC) using chemical cross-linking coupled with mass-spectrometry (XL-MS). The protocol does not require purification and is broadly applicable, facilitating determination of native structures in cell lysates and in non-disrupted cells as well as in purified complexes.

Aminoacyl-tRNA synthetases of the multi-tRNA synthetase complex and their role in tumorigenesis.

In mammalian cells, 20 aminoacyl-tRNA synthetases (AARS) catalyze the ligation of amino acids to their cognate tRNAs to generate aminoacylated-tRNAs. In higher eukaryotes, 9 of the 20 AARSs, along with 3 auxiliary proteins, join to form the cytoplasmic multi-tRNA synthetase complex (MSC). The complex is absent in prokaryotes, but evolutionary expansion of MSC constituents, primarily by addition of novel interacting domains, facilitates formation of subcomplexes that join to establish the holo-MSC.

Cotranslational interaction of human EBP50 and ezrin overcomes masked binding site during complex assembly.

Multiprotein assemblages are the intracellular workhorses of many physiological processes. Assembly of constituents into complexes can be driven by stochastic, domain-dependent, posttranslational events in which mature, folded proteins specifically interact. However, inaccessibility of interacting surfaces in mature proteins (e.

Acoustic propagation in gassy intertidal marine sediments: An experimental study.

The need to predict acoustic propagation through marine sediments that contain gas bubbles has become increasingly important for civil engineering and climate studies. There are relatively few in situ acoustic wave propagation studies of muddy intertidal sediments, in which bubbles of biogenic gas (generally methane, a potent greenhouse gas) are commonly found. We used a single experimental rig to conduct two in situ intertidal acoustical experiments to improve understanding of acoustic remote sensing of gassy sediments, eventually including gas bubble size distributions.

Screening of CRISPR-Cas9-generated point mutant mice using MiSeq and locked nucleic acid probe PCR.

CRISPR-Cas9-mediated, site-directed mutagenesis in mice generates mosaic founder mice with varied efficiency of desired point mutation and other non-homologous end-joined variants. Here, we present a protocol for design, sample preparation, and analysis for identification of mice with the desired mutation. Deep sequencing provides the proportion of reads of a particular allele for each mouse line.

The zinc-binding domain of mammalian prolyl-tRNA synthetase is indispensable for catalytic activity and organism viability.

Aminoacyl-tRNA synthetases (AARS) participate in decoding the genome by catalyzing conjugation of amino acids to their cognate tRNAs. During evolution, biochemical and environmental conditions markedly influenced the sequence and structure of the 20 AARSs, revealing adaptations dictating canonical and orthogonal activities. Here, we investigate the function of the appended Zn-binding domain (ZBD) in the bifunctional AARS, glutamyl-prolyl-tRNA synthetase (GluProRS).

Systematic Review on Which Analytics and Learning Methodologies Are Applied in Primary and Secondary Education in the Learning of Robotics Sensors.

Robotics technology has become increasingly common both for businesses and for private citizens. Primary and secondary schools, as a mirror of societal evolution, have increasingly integrated science, technology, engineering and math concepts into their curricula. Our research questions are: "In teaching robotics to primary and secondary school students, which pedagogical-methodological interventions result in better understanding and knowledge in the use of sensors in educational robotics?", and "In teaching robotics to primary and secondary school students, which analytical methods related to Learning Analytics processes are proposed to analyze and reflect on students' behavior in their learning of concepts and skills of sensors in educational robotics?".