Translational recoding by chemical modification of non-AUG start codon ribonucleotide bases

In contrast to prokaryotes wherein GUG and UUG are permissive start codons, initiation frequencies from non-AUG codons are generally low in eukaryotes, with CUG being considered as strongest. Here, we report that combined 5-cytosine methylation (5mC) and pseudouridylation (Ψ) of near-cognate non-AUG start codons convert GUG and UUG initiation strongly favored over CUG initiation in eukaryotic translation under a certain context. This prokaryotic-like preference is attributed to enhanced NUG initiation by Ψ in the second base and reduced CUG initiation by 5mC in the first base. Molecular dynamics simulation analysis of tRNAiMet anticodon base pairing to the modified codons demonstrates that Ψ universally raises the affinity of codon:anticodon pairing within the ribosomal preinitiation complex through partially mitigating discrimination against non-AUG codons imposed by eukaryotic initiation factor 1. We propose that translational control by chemical modifications of start codon bases can offer a new layer of proteome diversity regulation and therapeutic mRNA technology.

Atopic Dermatitis: Disease Characteristics and Comorbidities in Smoking and Nonsmoking Patients from the TREATgermany Registry

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a multifactorial genesis including genetic predispositions and environmental risk and trigger factors. One of the latter possibly is smoking, indicated by an increased prevalence of AD in adults and children that are actively or passively exposed to cigarette smoke.

OBJECTIVES

In this study AD characteristics and its atopic comorbidities are compared in smoking and nonsmoking AD patients.

METHODS

TREATgermany is a non-interventional clinical registry which includes patients with moderate to severe AD in Germany. Baseline data of patients included into TREATgermany from inception in June 2016 to April 2020 in 39 sites across Germany was analyzed comparing AD disease characteristics and comorbidities in smokers versus non-smokers.

RESULTS

Of 921 patients, 908 (male: 58.7%) with a mean age of 41.9 ± 14.4 reported their smoking status. The objective Scoring of Atopic Dermatitis (oSCORAD) did not differ between smokers (n=352; 38.8%) and nonsmokers, however lesions' intensity of oozing/crusts and excoriations as well as patient global assessment scores (PGA) of AD severity were higher in smoking as opposed to nonsmoking patients. Smokers reported a lower number of weeks with well-controlled AD and more severe pruritus than nonsmokers. Total IgE levels were more elevated in smokers and they displayed a younger age at initial diagnosis of bronchial asthma. After adjustment for potential confounders, the increased intensity of oozing/crusts, the reduced number of weeks with well-controlled AD and the greater pruritus remained different in smokers compared to nonsmokers. In addition, smoking patients with adult-onset AD showed a 2.5 times higher chance of involvement of the feet.

CONCLUSIONS

German registry data indicate that AD patients who smoke have a higher disease burden with a different distribution pattern of lesions in adult-onset AD.

Human oncoprotein 5MP suppresses general and repeat-associated non-AUG translation via eIF3 by a common mechanism

eIF5-mimic protein (5MP) is a translational regulatory protein that binds the small ribosomal subunit and modulates its activity. 5MP is proposed to reprogram non-AUG translation rates for oncogenes in cancer, but its role in controlling non-AUG initiated synthesis of deleterious repeat-peptide products, such as FMRpolyG observed in fragile-X-associated tremor ataxia syndrome (FXTAS), is unknown. Here, we show that 5MP can suppress both general and repeat-associated non-AUG (RAN) translation by a common mechanism in a manner dependent on its interaction with eIF3. Essentially, 5MP displaces eIF5 through the eIF3c subunit within the preinitiation complex (PIC), thereby increasing the accuracy of initiation. In Drosophila, 5MP/Kra represses neuronal toxicity and enhances the lifespan in an FXTAS disease model. These results implicate 5MP in protecting cells from unwanted byproducts of non-AUG translation in neurodegeneration.

Gcn2 eIF2α kinase mediates combinatorial translational regulation through nucleotide motifs and uORFs in target mRNAs

The protein kinase Gcn2 is a central transducer of nutritional stress signaling important for stress adaptation by normal cells and the survival of cancer cells. In response to nutrient deprivation, Gcn2 phosphorylates eIF2α, thereby repressing general translation while enhancing translation of specific mRNAs with upstream ORFs (uORFs) situated in their 5'-leader regions. Here we performed genome-wide measurements of mRNA translation during histidine starvation in fission yeast Schizosaccharomyces pombe. Polysome analyses were combined with microarray measurements to identify gene transcripts whose translation was up-regulated in response to the stress in a Gcn2-dependent manner. We determined that translation is reprogrammed to enhance RNA metabolism and chromatin regulation and repress ribosome synthesis. Interestingly, translation of intron-containing mRNAs was up-regulated. The products of the regulated genes include additional eIF2α kinase Hri2 amplifying the stress signaling and Gcn5 histone acetyl transferase and transcription factors, together altering genome-wide transcription. Unique dipeptide-coding uORFs and nucleotide motifs, such as '5'-UGA(C/G)GG-3', are found in 5' leader regions of regulated genes and shown to be responsible for translational control.

Baseline characteristics, disease severity and treatment history of patients with atopic dermatitis included in the German AD Registry TREATgermany

BACKGROUND

The Atopic Dermatitis (AD) TREATgermany registry was initiated by the German Society for Dermatology (DDG) in 2011 to evaluate the 'real-life' situation of health care for patients with AD.

OBJECTIVES

Interim data analysis on baseline characteristics as well as current and prescribed systemic treatments of the TREATgermany registry patients.

METHODS

Patients (≥18 years) with moderate-to-severe AD [objective (o)SCORAD > 20], or with current or previous anti-inflammatory systemic treatment for AD within 24 months, were included and are followed up over at least 24 months. To assess clinical signs, the eczema area severity index (EASI, 0-72), the oSCORAD (0-83) and the Investigator Global Assessment (IGA; 6-point scale) were used. The disease severity was globally scored by the patients [Patient Global Assessment (PGA); six-step Likert scale]. Disease symptoms were assessed by the patient-oriented eczema measure (POEM, 0-28) and numeric rating scales (NRS, 0-10). Health-related quality of life was measured using the dermatological life quality index (DLQI, 0-30).

RESULTS

A total of 612 patients were recruited across 32 sites between 06/2016 and 01/2019 (mean age: 42.6 ± 14.2 years; mean oSCORAD: 40.8 ± 16.3). The mean POEM score was 16.3 ± 7.5. Pruritus was rated highest among subjective symptoms (NRS: 5.4 ± 2.7). The mean DLQI value was 11.3 ± 7.5. The frequency of arterial hypertension was lower (20.8%) compared with the general population, whilst this was higher for depression (10%). More than 60% of the patients had received systemic glucocorticosteroids, and 36.8% had received cyclosporine A prior to inclusion. Dupilumab was the leading substance documented as either 'current' (12.1%) or 'prescribed' (31.4%) at baseline.

CONCLUSIONS

These 'real-life' data clearly demonstrate the substantial disease burden. Most of TREATgermany patients were already treated with or prescribed dupilumab at baseline. Moreover, current findings indicate the urgent need for further alternative agents in order to achieve a perceptible improvement of quality of life of patients with moderate-to-severe AD.

Neural Precursor Cells as Carriers for a Gene Therapeutical Approach in Tumor Therapy

Conventional therapeutical approaches such as surgery, radiotherapy, or chemotherapy have been shown to be rather unsuccessful in the treatment of infiltrative growing tumors such as the malignant glioblastoma multiforme. Thus, new therapeutical strategies have to be developed that are suitable for inducing cell death also in migrating tumor cells. These new therapeutical stategies include cell and/or gene therapeutical approaches. We demonstrate that glial-restricted progenitor cells as well as embryonic stem cell-derived neural stem cells belong to cell populations applicable to such therapeutical concepts. Both cell types can be efficiently transduced using a third-generation high-capacity “gutless” adenoviral vector, and show a tropism for the F98 glioma cells by migrating towards a spheroid of F98 glioma cells with a tendency to form a barrier around the tumor spheroid in an in vitro tumor confrontation model. Moreover, in a migration assay, secretion products of glial-restricted precursor cells have shown a potency to inhibit the migratory activity of glioma cells in vitro. In vivo, F98 glioma cell-derived tumor formation in the right striatum resulted in migration of glial as well as neural precursor cells towards the tumor area when cotransplanted in the corpus callosum of the contralateral hemisphere. After arrival, both cell types surround the tumor mass and even invade the experimentally induced tumor. These data indicate that glial-restricted as well as embryonic stem cell-derived neural precursor cells are good candidates as carriers for an ex vivo gene therapeutical approach in tumor therapy.

[Cain. The separation of shame and guilt exemplified in Genesis]

Referring to Cain's fratricide, the authors investigate the origin of guilt. They assume that feelings of shame preceded feelings of guilt and that the former are the cause of the destructiveness and persistence of the latter.