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Subarachnoid haemorrhage (SAH) is a devastating cerebrovascular disease which has a high morbidity and mortality. The phenotypic transformation of smooth muscle cells (SMCs) lead to neurovascular injury after SAH. However, the underlying mechanism remains unclear. In the present study, we aimed to investigate the potential role of ET-1/ETAR on the phenotypic transformation of SMCs after SAH. The models of SAH were established in vivo and vitro. We observed ET-1 secretion by endothelial cells was increased, and the phenotypic transformation of SMCs was aggravated after SAH. Knocking down ETAR inhibited the phenotypic transformation of SMCs, decreased the migration ability of SMCs in vitro. Moreover, Knocking down ETAR ameliorated cerebral ischaemia and alleviated dysfunction of neurological function in vivo. In addition, Exogenous ET-1 increased the migration ability of SMCs and aggravated the phenotypic transformation of SMCs in vitro, which were partly reversed by the antagonist of Erk1/2 - SCH772984. Taken together, our results demonstrated that endothelial ET-1 aggravated the phenotypic transformation of SMCs after SAH. Knocking down ETAR inhibited the phenotypic transformation of SMCs through ERK/KLF4 thus ameliorating neurovascular injury after SAH. We also revealed that ET-1/ETAR is a potential therapeutic target after SAH.In this issue of Structure, Juaire et al. use X-ray crystallography, biophysical tools, and cell-based assays to investigate disease-associated variants of the SRP54 GTPase and to demonstrate that defects in SRP-mediated protein secretion can explain phenotypes of severe neutropenia with Shwachman-Diamond-syndrome-like symptoms.The canonical DNA glycosylase role is global base damage repair but includes functions in epigenetic gene regulation, immune response modulation, replication, and transcription. In this issue of Structure, Eckenroth et al. (2020) present the NEIL2 glycosylase structure. Its catalytic domain flexibility differentiates it from most other glycosylases and suggests novel regulatory mechanisms.The delineation of disease entities is complex, yet recent advances in the molecular characterization of diseases provide opportunities to designate diseases in a biologically valid manner. Here, we have formalized an approach to the delineation of Mendelian genetic disorders that encompasses two distinct but inter-related concepts (1) the gene that is mutated and (2) the phenotypic descriptor, preferably a recognizably distinct phenotype. We assert that only by a combinatorial or dyadic approach taking both of these attributes into account can a unitary, distinct genetic disorder be designated. We propose that all Mendelian disorders should be designated as "GENE-related phenotype descriptor" (e.g., "CFTR-related cystic fibrosis"). This approach to delineating and naming disorders reconciles the complexity of gene-to-phenotype relationships in a simple and clear manner yet communicates the complexity and nuance of these relationships.The National Human Genome Research Institute (NHGRI) recently published a new strategic vision for the future of human genomics, the product of an extensive, multi-year engagement with numerous research, medical, educational, and public communities. The theme of this 2020 vision-The Forefront of Genomics-reflects NHGRI's critical role in providing responsible stewardship of the field of human genomics, especially as genomic methods and approaches become increasingly disseminated throughout biomedicine. Embracing that role, the new NHGRI strategic vision features a set of guiding principles and values that provide an ethical and moral framework for the field. One principle emphasizes the need to champion a diverse genomics workforce because "the promise of genomics cannot be fully achieved without attracting, developing, and retaining a diverse workforce, which includes individuals from groups that are currently underrepresented in the genomics enterprise." To build on the remarkable metamorphosis of the field over the last three decades, enhancing the diversity of the genomics workforce must be embraced as an urgent priority. Toward that end, NHGRI recently developed an "action agenda" for training, employing, and retaining a genomics workforce that reflects the diversity of the US population.POLR3B encodes the second-largest catalytic subunit of RNA polymerase III, an enzyme involved in transcription. Bi-allelic pathogenic variants in POLR3B are a well-established cause of hypomyelinating leukodystrophy. We describe six unrelated individuals with de novo missense variants in POLR3B and a clinical presentation substantially different from POLR3-related leukodystrophy. Resiquimod These individuals had afferent ataxia, spasticity, variable intellectual disability and epilepsy, and predominantly demyelinating sensory motor peripheral neuropathy. Protein modeling and proteomic analysis revealed a distinct mechanism of pathogenicity; the de novo POLR3B variants caused aberrant association of individual enzyme subunits rather than affecting overall enzyme assembly or stability. We expand the spectrum of disorders associated with pathogenic variants in POLR3B to include a de novo heterozygous POLR3B-related disorder.Toxin-antidote elements (TAs) are selfish genetic dyads that spread in populations by selectively killing non-carriers. TAs are common in prokaryotes, but very few examples are known in animals. link2 Here, we report the discovery of maternal-effect TAs in both C. tropicalis and C. briggsae, two distant relatives of C. elegans. In C. tropicalis, multiple TAs combine to cause a striking degree of intraspecific incompatibility five elements reduce the fitness of >70% of the F2 hybrid progeny of two Caribbean isolates. We identified the genes underlying one of the novel TAs, slow-1/grow-1, and found that its toxin, slow-1, is homologous to nuclear hormone receptors. Remarkably, although previously known TAs act during embryonic development, maternal loading of slow-1 in oocytes specifically slows down larval development, delaying the onset of reproduction by several days. Finally, we found that balancing selection acting on linked, conflicting TAs hampers their ability to spread in populations, leading to more stable genetic incompatibilities. Our findings indicate that TAs are widespread in Caenorhabditis species and target a wide range of developmental processes and that antagonism between them may cause lasting incompatibilities in natural populations. We expect that similar phenomena exist in other animal species.One of the main reasons why amputees report poor satisfaction with prostheses is their excessive weight perceived,1 despite the fact that they typically weigh less than half of the natural limb.2 Weight perception can be a subjective percept that is influenced by cognitive processes.3-5 Even though recent developments in prosthetics have shown that sensory feedback restoration positively influences cognitive aspects (as embodiment of the device and cognitive load),6,7 the potential benefits on prosthesis heaviness perception have never been investigated. In this study, we explored this matter using intraneural sensory feedback in a transfemoral (above-knee) amputee. We hypothesized that providing neural feedback would affect the integration of the prosthesis in the amputee's body schema, hence influencing the prosthesis weight perception. The results indicate that, after performing an over-ground walking task, the sensory feedback allowed a 23% decrease in prosthesis heaviness perception compared to the no feedback condition. Our hypothesis was confirmed by a significant increase in the embodiment of the prosthesis (by 60.5%) and confidence (by 36%) while walking with the sensory feedback. A subsequent dual task (i.e., walking while spelling backward) showed that the sensory feedback abolished the reduction of walking speed and accuracy observed during the no-feedback condition and normally seen with increased mental workload, suggesting a cognitive integration of the system. These results show the importance of providing close-to-natural sensations from the missing limb to allow a good integration of the prostheses and increase the satisfaction of their users. VIDEO ABSTRACT.Tissue bending is vital to plant development, as exemplified by apical hook formation during seedling emergence by bending of the hypocotyl. How tissue bending is coordinated during development remains poorly understood, especially in plants where cells are attached via rigid cell walls. Asymmetric distribution of the plant hormone auxin underlies differential cell elongation during apical hook formation. Yet the underlying mechanism remains unclear. Here, we demonstrate spatial correlation between asymmetric auxin distribution, methylesterified homogalacturonan (HG) pectin, and mechanical properties of the epidermal layer of the hypocotyl in Arabidopsis. Genetic and cell biological approaches show that this mechanochemical asymmetry is essential for differential cell elongation. We show that asymmetric auxin distribution underlies differential HG methylesterification, and conversely changes in HG methylesterification impact the auxin response domain. Our results suggest that a positive feedback loop between auxin distribution and HG methylesterification underpins asymmetric cell wall mechanochemical properties to promote tissue bending and seedling emergence.Mismatch repair (MMR) safeguards genome stability through recognition and excision of DNA replication errors.1-4 How eukaryotic MMR targets the newly replicated strand in vivo has not been established. MMR reactions reconstituted in vitro are directed to the strand containing a preexisting nick or gap,5-8 suggesting that strand discontinuities could act as discrimination signals. Another candidate is the proliferating cell nuclear antigen (PCNA) that is loaded at replication forks and is required for the activation of Mlh1-Pms1 endonuclease.7-9 Here, we discovered that overexpression of DNA ligase I (Cdc9) in Saccharomyces cerevisiae causes elevated mutation rates and increased chromatin-bound PCNA levels and accumulation of Pms1 foci that are MMR intermediates, suggesting that premature ligation of replication-associated nicks interferes with MMR. We showed that yeast Pms1 expression is mainly restricted to S phase, in agreement with the temporal coupling between MMR and DNA replication.10 Restricting Pms1 expression to the G2/M phase caused a mutator phenotype that was exacerbated in the absence of the exonuclease Exo1. This mutator phenotype was largely suppressed by increasing the lifetime of replication-associated DNA nicks, either by reducing or delaying Cdc9 ligase activity in vivo. Therefore, Cdc9 dictates a window of time for MMR determined by transient DNA nicks that direct the Mlh1-Pms1 in a strand-specific manner. Because DNA nicks occur on both newly synthesized leading and lagging strands,11 these results establish a general mechanism for targeting MMR to the newly synthesized DNA, thus preventing the accumulation of mutations that underlie the development of human cancer.Organismal phenotypes usually have a quantitative distribution, and their genetic architecture can be studied by genome-wide association (GWA) mapping approaches. In most of such studies, it has become clear that many genes of moderate or small effects contribute to the phenotype.1-4 Hence, the attention has turned toward the loci falling below the GWA cut-off, which may contribute to the phenotype through modifier interactions with a set of core genes, as proposed in the omnigenic model.5 One can thus predict that both moderate effect GWA-derived candidate genes and randomly chosen genes should have a similar likelihood to affect a given phenotype when they are analyzed via gene disruption assays. We have tested this hypothesis by using an automated phenotyping system for Drosophila pupal phenotypes.6,7 We first identified candidate genes for pupal length in a GWA based on the Drosophila Genetic Reference Panel (DGRP)8,9 and showed that most of these candidate genes are indeed involved in the phenotype. link3 We then randomly chose genes below a GWA significance threshold and found that three-quarters of them had also an effect on the trait with comparable effect sizes as the GWA candidate genes.

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