-
Brain : a Journal of Neurology Jun 2024Charcot-Marie-Tooth (CMT) disease is a neuromuscular disorder affecting the peripheral nervous system. The diagnostic yield in demyelinating CMT (CMT1) is typically...
Charcot-Marie-Tooth (CMT) disease is a neuromuscular disorder affecting the peripheral nervous system. The diagnostic yield in demyelinating CMT (CMT1) is typically ∼80-95%, of which at least 60% is due to the PMP22 gene duplication. The remainder of CMT1 is more genetically heterogeneous. We used whole exome and whole genome sequencing data included in the GENESIS database to investigate novel causal genes and mutations in a cohort of ∼2,670 individuals with CMT neuropathy. A recurrent heterozygous missense variant p.Thr1424Met in the recently described CMT gene ITPR3, encoding IP3R3 (inositol 1,4,5-trisphosphate receptor 3) was identified. This previously reported p.Thr1424Met change was present in 33 affected individuals from nine unrelated families from multiple populations, representing an unusual recurrence rate at a mutational hotspot, strengthening the gene-disease relationship (GnomADv4 allele frequency 1.76e-6). Sanger sequencing confirmed the co-segregation of the CMT phenotype with the presence of the mutation in autosomal dominant and de novo inheritance patterns, including a four-generation family with multiple affected second-degree cousins. Probands from all families presented with slow nerve conduction velocities, matching the diagnostic category of CMT1. Remarkably, we observed a uniquely variable clinical phenotype for age at onset and phenotype severity in p.Thr1424Met carrying patients, even within families. Finally, we present data supportive of a dominant-negative effect of the p.Thr1424Met mutation with associated changes in protein expression in patient-derived cells.
PubMed: 38938188
DOI: 10.1093/brain/awae206 -
Plant Disease Jun 2024The first tri-segmented viruses in the family Rhabdoviridae were recently discovered by exploring publicly available plant datasets in several hosts, including alfalfa...
The first tri-segmented viruses in the family Rhabdoviridae were recently discovered by exploring publicly available plant datasets in several hosts, including alfalfa (Medicago sativa L.) (Bejerman et al. 2023). They were classified in a novel genus "Trirhavirus" within the family Rhabdoviridae. The trirhavirus identified in alfalfa was named Medicago trirhavirus 1 (MeTRV1). Here we report the first confirmation of MeTRV1 in commercial alfalfa fields in Washington State, USA. Samples were collected in 2019-2021 in Benton and Grant Counties, WA. The alfalfa leaves in which the virus was detected displayed irregular chlorotic spotting (Fig.1). Total RNA extraction, library preparation, high throughput sequencing, and bioinformatics analysis were performed as described in Nemchinov et al (2023). Raw reads were trimmed with Trimmomatic 0.39 (Bolger at al. 2014). SPAdes 3.15.5 (Bankevich et al. 2012) was used for assembly. MeTRV1 was identified in four plants out of 100 tested and three complete RNA segments were recovered from one of them. For clarity, the virus found in the alfalfa field samples was designated MeTRV1-Wa. De novo assembly resulted in three contigs, which, when subjected to BLASTn analyses, aligned to the respective RNA segments of MeTRV1. The first contig was 6,498 nucleotides (nts)-long, 99.4% identical to RNA1 of MeTRV1 (BK064256.1), and 5,922 reads mapped to it (coverage 125x). RNA1 of MeTRV1-Wa encoded a protein 2,040 amino acid (aa)-long that aligned with protein L of MeTRV1 (DBA36559.1, 99.8%). The second contig was 4,014 nts-long and 95.2% identical to the RNA2 of MetRV1 (BK064257.1) with 1,751 reads mapping (coverage 59x). It contained four open reading frames (ORFs) encoding proteins N (445 aa, 99.8%, DBA36560.1); P2 (343 aa, 99.4%, DBA36561.1); P3 (183 aa, 99.4%, DBA36562.1); and P4 (72 aa, 98.6%, DBA36563.1). Altogether, 4,653 reads mapped to the third contig (coverage 131x) that was 4,889 nts-long and 99.1% identical to the RNA 3 segment of MeTRV1 (BK064258.1). RNA3 of MeTRV1-Wa encoded four proteins: P6 (274 aa, 100%, DBA36565.1); P7 (189 aa, 99.5%, DBA36566.1); P8 (514 aa, 99 %, DBA36567.1); and P5 (303 aa, 99.7%, DBA36564.1). The 5' trailer of each RNA segment had a nearly identical 24 nts at the end. Genomic organization of the MeTRV1-Wa and the locations of its ORFs are shown in Fig.2. To confirm the virus's presence, two sets of primers were designed based on the predicted sequence of the viral RNA 3 segment. The correct-size products were amplified in RT-PCR assays with RNA extracted from infected plants (Fig.3) and verified by Sanger sequencing. Besides MeTRV1-Wa, sequences of the following viruses known to cause symptoms in alfalfa were identified in the same library: alfalfa mosaic virus, bean leafroll virus, lucerne transient streak virus, and pea streak virus. Thus, the observed symptomatology may not be clearly attributed to MeTRV1-Wa due to coinfecting organisms. However, a possible association of the disease symptoms with the virus presence could be suggested based on comparison with both asymptomatic and symptomatic plants negative for MeTRV1-Wa (Fig.1). Since plant rhabdoviruses are recognized as a cause of economic losses in alfalfa and other major crops and are transmitted by insects (Bejerman et al. 2011, 2015; Jackson et al. 2005; Man and Dietzgen 2014), this first experimental confirmation of the occurrence of the new virus in the U.S. alfalfa is important for understanding its origin, distribution, and pathogenic potential.
PubMed: 38937929
DOI: 10.1094/PDIS-05-24-1132-PDN -
Nature Chemistry Jun 2024The 1,2-arylheteroaryl ethane motif stands as a privileged scaffold with promising implications in drug discovery. Conventional de novo syntheses of these molecules have...
The 1,2-arylheteroaryl ethane motif stands as a privileged scaffold with promising implications in drug discovery. Conventional de novo syntheses of these molecules have relied heavily on pre-functionalized synthons, entailing harsh conditions and multi-step processes. Here, to address these limitations, we present a modular approach for the direct synthesis of 1,2-arylheteroaryl ethanes using feedstock chemicals, including ethylene, arenes and heteroarenes. We disclosed a photo triplet-energy-transfer-initiated radical cascade process, leveraging homolytic cleavage of C-S bonds in aryl sulfonium salts as the key step to access aryl radicals with excellent regioselectivity. This method allows for rapid structural diversification of bioactive molecules, showcasing excellent functional group tolerance and streamlining the synthesis of bioactive compounds and their derivatives. Furthermore, our approach can be extended to propylene, non-gaseous terminal alkenes and various other electrophilic radical precursors, including heteroaryl radicals, hydroxyl radicals, trifluoromethyl radicals and α-carbonyl alkyl radicals. This study highlights the significance of radical polarity matching in designing selective multi-component couplings.
PubMed: 38937591
DOI: 10.1038/s41557-024-01560-7 -
Journal of Medical Genetics Jun 2024Tatton-Brown-Rahman syndrome (TBRS; OMIM 615879), also known as DNA methyltransferase 3 alpha ()-overgrowth syndrome (DOS), was first described by Tatton-Brown in 2014....
BACKGROUND
Tatton-Brown-Rahman syndrome (TBRS; OMIM 615879), also known as DNA methyltransferase 3 alpha ()-overgrowth syndrome (DOS), was first described by Tatton-Brown in 2014. This syndrome is characterised by overgrowth, intellectual disability and distinctive facial features and is the consequence of germline loss-of-function variants in , which encodes a DNA methyltransferase involved in epigenetic regulation. Somatic variants of are frequently observed in haematological malignancies, including acute myeloid leukaemia (AML). To date, 100 individuals with TBRS with de novo germline variants have been described. We aimed to further characterise this disorder clinically and at the molecular level in a nationwide series of 24 French patients and to investigate the correlation between the severity of intellectual disability and the type of variant.
METHODS
We collected genetic and medical information from 24 individuals with TBRS using a questionnaire released through the French National AnDDI-Rares Network.
RESULTS
Here, we describe the first nationwide French cohort of 24 individuals with germline likely pathogenic/pathogenic variants in , including 17 novel variants. We confirmed that the main phenotypic features were intellectual disability (100% of individuals), distinctive facial features (96%) and overgrowth (87%). We highlighted novel clinical features, such as hypertrichosis, and further described the neurological features and EEG results.
CONCLUSION
This study of a nationwide cohort of individuals with TBRS confirms previously published data and provides additional information and clarifies clinical features to facilitate diagnosis and improve care. This study adds value to the growing body of knowledge on TBRS and broadens its clinical and molecular spectrum.
PubMed: 38937076
DOI: 10.1136/jmg-2024-110031 -
The Science of the Total Environment Jun 2024The present study aims to evaluate the effects of 2-ethylhexyldiphenyl phosphate (EHDPP) on glycolipid metabolism in vivo. Adult male zebrafish were exposed to various...
The present study aims to evaluate the effects of 2-ethylhexyldiphenyl phosphate (EHDPP) on glycolipid metabolism in vivo. Adult male zebrafish were exposed to various concentrations (0, 1, 10, 100 and 250 μg/L) of EHDPP for 28 days, and changes in lipid and glucose levels were measured. Results indicated significant liver damages in the 100 and 250 μg/L EHDPP groups, which both exhibited significant decreases in hepatic somatic index (HSI), elevated activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum and liver, as well as hepatocyte vacuolation and nuclear pyknosis. Exposure to 100 and 250 μg/L EHDPP led to significant reductions in serum and liver cholesterol (TC), triglycerides (TGs), and lipid droplet deposition, indicating a significant inhibition of EHDPP on hepatic lipid accumulation. Lipidomic analyses manifested that 250 μg/L EHDPP reduced the levels of 103 lipid metabolites which belong to glycerides (TGs, diglycerides, and monoglycerides), fatty acyles (fatty acids), sterol lipids (cholesterol, bile acids), sphingolipids, and glycerophospholipids, and downregulated genes involved in de novo synthesis of fatty acids (fas, acc, srebp1, and dagt2), while upregulated genes involved in fatty acid β-oxidation (pparα and cpt1). KEGG analyses revealed that EHDPP significantly disrupted glycerolipid metabolism, steroid biosynthesis and fatty acid biosynthesis pathways. Collectively, the results showed that EHDPP induced lipid reduction in zebrafish liver, possibly through inhibiting lipid synthesis and disrupting glycerolipid metabolism. Our findings provide a theoretical basis for evaluating the ecological hazards and health effects of EHDPP on glycolipid metabolism.
PubMed: 38936724
DOI: 10.1016/j.scitotenv.2024.174248 -
Cell Jun 2024Interleukin (IL)-23 and IL-17 are well-validated therapeutic targets in autoinflammatory diseases. Antibodies targeting IL-23 and IL-17 have shown clinical efficacy but...
Interleukin (IL)-23 and IL-17 are well-validated therapeutic targets in autoinflammatory diseases. Antibodies targeting IL-23 and IL-17 have shown clinical efficacy but are limited by high costs, safety risks, lack of sustained efficacy, and poor patient convenience as they require parenteral administration. Here, we present designed miniproteins inhibiting IL-23R and IL-17 with antibody-like, low picomolar affinities at a fraction of the molecular size. The minibinders potently block cell signaling in vitro and are extremely stable, enabling oral administration and low-cost manufacturing. The orally administered IL-23R minibinder shows efficacy better than a clinical anti-IL-23 antibody in mouse colitis and has a favorable pharmacokinetics (PK) and biodistribution profile in rats. This work demonstrates that orally administered de novo-designed minibinders can reach a therapeutic target past the gut epithelial barrier. With high potency, gut stability, and straightforward manufacturability, de novo-designed minibinders are a promising modality for oral biologics.
PubMed: 38936360
DOI: 10.1016/j.cell.2024.05.052 -
Reproductive Biomedicine Online Apr 2024Does routine clinical practice require an increase in the resolution of preimplantation genetic testing for aneuploidies (PGT-A) to detect segmental aneuploidies ≤5 Mb?
RESEARCH QUESTION
Does routine clinical practice require an increase in the resolution of preimplantation genetic testing for aneuploidies (PGT-A) to detect segmental aneuploidies ≤5 Mb?
DESIGN
This retrospective study analysed 963 trophectoderm biopsies from 346 couples undergoing PGT between 2019 and 2023. Segmental aneuploidies ≥1 Mb were reported. The characteristics, clinical interpretation and concordance of segmental aneuploidies ≤5 Mb were analysed.
RESULTS
The incidence of segmental aneuploidies was 15.1% (145/963) in blastocysts, with segmental aneuploidies of ≤5 Mb accounting for 2.3% (22/963). The size of the segmental aneuploidies showed a skewed distribution. Segmental aneuploidies ≤5 Mb were found to occur more frequently on the q arm of the chromosome, compared with the p arm. Losses of ≤5 Mb segmental aneuploidies were more prevalent than gains, with 17 deletions compared with 5 duplications. Of the segmental aneuploidies, 63.6% (14/22) ≤5 Mb were de novo, and 50.0% (7/14) of de-novo segmental aneuploidies were pathogenic/likely pathogenic (P/LP) copy number variations, accounting for 0.7% of 963 blastocysts. For blastocysts carrying ≤5 Mb segmental aneuploidies, a re-analysis of back-up biopsy samples showed that 35.7% of de-novo segmental aneuploidies (5/14) were not detected in the back-up samples. Cases were reported in which prenatal diagnosis (amniocentesis) revealed the absence of embryonic ≤5 Mb segmental aneuploidies detected at the blastocyst stage.
CONCLUSIONS
The incidence of P/LP de-novo ≤5 Mb segmental aneuploidies in human blastocysts is extremely low. There is no compelling need to increase the resolution of PGT-A to 5 Mb in routine clinical practice.
PubMed: 38936339
DOI: 10.1016/j.rbmo.2024.103991 -
European Journal of Cancer (Oxford,... Jun 2024Myocarditis is the most lethal cardiovascular immune related adverse events with a low incidence, depending on the studies. We prospectively studied the potential...
INTRODUCTION
Myocarditis is the most lethal cardiovascular immune related adverse events with a low incidence, depending on the studies. We prospectively studied the potential interest of a systematic screening to early detect immune related myocarditis and confirm the incidence of immune-induced myocarditis in advanced lung cancer and the impact of troponin systematic screening in early detection of other major cardiovascular events (MACE).
MATERIAL AND METHODS
This prospective bicentric study includes adults who received at least one dose of immune checkpoint inhibitor (ICI) for advanced lung cancer. Cardiac biomarkers dosage, ECG and transthoracic echography (TTE) were done at baseline. Diagnosis of myocarditis was based on European Society of Cardiology recommendations. MACEs were reported during the observation period.
RESULTS
Among 298 patients, 5 (1.68 %) immune-induced myocarditis occurred, all being asymptomatic with at first troponin elevation, treated by corticosteroids and ICI's discontinuation. No attributable death occurred, and no specific clinical characteristics were identified with myocarditis onset. Three patients were rechallenged with ICI after troponin normalization in the absence of other therapeutic options. Recurrence occurred in 2 patients, with a re-increase of troponin and a de novo modification of the ECG. Systematic cardiovascular screening also led to 14 cardiovascular diseases detection and 11 MACEs during ICI.
CONCLUSION
Systematic cardiovascular screening has uncovered slightly more immuno-induced myocarditis cases than reported previously, but without altering treatment strategies due to their subclinical nature. Additionally, it helps detecting other cardiovascular diseases in this comorbid population.
PubMed: 38936104
DOI: 10.1016/j.ejca.2024.114191 -
JACC. Heart Failure Jun 2024Cardiac allograft vasculopathy is characterized by increased coronary intimal thickness and is a leading cause of death in heart transplant (HTx) recipients despite the...
BACKGROUND
Cardiac allograft vasculopathy is characterized by increased coronary intimal thickness and is a leading cause of death in heart transplant (HTx) recipients despite the routine use of statins. The experience with inhibitors of proprotein convertase subtilisin-kexin type 9 in HTx recipients is limited. Our hypothesis was that lowering cholesterol with the proprotein convertase subtilisin-kexin type 9inhibitor evolocumab would reduce coronary intimal thickness in these patients without compromising safety.
OBJECTIVES
This double blind, randomized trial was conducted to test whether evolocumab reduces the burden of cardiac allograft vasculopathy.
METHODS
Patients who had received a cardiac allograft at one of the Nordic transplant centers within the prior 4 to 8 weeks were randomized to monthly subcutaneous injections of evolocumab 420 mg or matching placebo. The primary endpoint was the baseline-adjusted maximal intimal thickness as measured by intracoronary ultrasound after 12 months' treatment.
RESULTS
The trial enrolled 128 patients between June 2019 and May 2022. Matched pairs of coronary ultrasound images were available for 56 patients assigned to evolocumab and 54 patients assigned to placebo. At 12 months, the adjusted mean difference in the maximal intimal thickness between the 2 arms was 0.017 mm (95% CI: -0.006 to 0.040; P = 0.14). The mean reduction in low-density lipoprotein cholesterol with evolocumab compared with placebo was 1.11 mmol/L (95% CI: 0.86-1.37 mmol/L). The use of evolocumab was not associated with an increase in adverse events.
CONCLUSIONS
Twelve months of treatment with evolocumab substantially reduced low-density lipoprotein cholesterol but did not reduce maximal coronary intimal thickness in HTx recipients. (Cholesterol Lowering With EVOLocumab to Prevent Cardiac Allograft Vasculopathy in De-novo Heart Transplant Recipients [EVOLVD]; NCT03734211).
PubMed: 38934968
DOI: 10.1016/j.jchf.2024.04.026 -
Genome Biology and Evolution Jun 2024De novo genes emerge from non-coding regions of genomes via succession of mutations. Among others, such mutations activate transcription and create a new open reading...
De novo genes emerge from non-coding regions of genomes via succession of mutations. Among others, such mutations activate transcription and create a new open reading frame (ORF). Although the mechanisms underlying ORF emergence are well documented, relatively little is known about the mechanisms enabling new transcription events. Yet, in many species a continuum between absent and very prominent transcription has been reported for essentially all regions of the genome. In this study we searched for de novo transcripts by using newly assembled genomes and transcriptomes of seven inbred lines of Drosophila melanogaster, originating from six European and one African population. This setup allowed us to detect sample specific de novo transcripts, and compare them to their homologous non-transcribed regions in other samples, as well as genic and intergenic control sequences. We studied the association with transposable elements and the enrichment of transcription factor motifs upstream of de novo emerged transcripts and compared them with regulatory elements. We found that de novo transcripts overlap with TEs more often than expected by chance. The emergence of new transcripts correlates with regions of high GC content and TE expression. Moreover, upstream regions of de novo transcripts are highly enriched with regulatory motifs. Such motifs are more enriched in new transcripts overlapping with TEs, particularly DNA TEs, and are more conserved upstream de novo transcripts than upstream their 'non-transcribed homologs'. Overall, our study demonstrates that TE insertion is important for transcript emergence, partly by introducing new regulatory motifs from DNA TE families.
PubMed: 38934893
DOI: 10.1093/gbe/evae134