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Amyotrophic lateral sclerosis (ALS) is a devastating neuromuscular disease characterized by progressive motor function and muscle mass loss. Despite extensive research in the field, the underlying causes of ALS remain incompletely understood, contributing to the absence of specific diagnostic and prognostic biomarkers and effective therapies. This study investigates the expression of long-non-coding RNAs (lncRNAs) in skeletal muscle as a potential source of biomarkers and therapeutic targets for the disease. The expression profiles of 12 lncRNAs, selected from the literature, were evaluated across different disease stages in tissue and muscle biopsies from the SOD1^G93A transgenic mouse model of ALS. Nine out of the 12 lncRNAs were differentially expressed, with Pvt1, H19 and Neat1 showing notable increases in the symptomatic stages of the disease, and suggesting their potential as candidate biomarkers to support diagnosis and key players in muscle pathophysiology in ALS. Furthermore, the progression of Myhas and H19 RNA levels across disease stages correlated with longevity in the SOD1^G93A animal model, effectively discriminating between long- and short-term survival individuals, thereby highlighting their potential as prognostic indicators. These findings underscore the involvement of lncRNAs, especially H19 and Myhas, in ALS pathophysiology, offering novel insights for diagnostic, prognostic and therapeutic targets.

The development of therapies to combat neurodegenerative diseases is widely recognized as a research priority. Despite recent advances in understanding their molecular basis, there is a lack of suitable early biomarkers to test selected compounds and accelerate their translation to clinical trials. We have investigated the utility of in vivo reporters of cytoprotective pathways (e.g. NRF2, p53) as surrogate early biomarkers of the ALS degenerative disease progression. We hypothesized that cellular stress observed in a model of ALS may precede overt cellular damage and could activate our cytoprotective pathway reporters. To test this hypothesis, we generated novel ALS-reporter mice by crossing the hTDP-43tg model into our oxidative stress/inflammation (Hmox1; NRF2 pathway) and DNA damage (p21; p53 pathway) stress reporter models. Histological analysis of reporter expression in a homozygous hTDP-43tg background demonstrated a time-dependent and tissue-specific activation of the reporters in tissues directly associated with ALS, before moderate clinical signs are observed. Further work is warranted to determine the specific mechanisms by which TDP-43 accumulation leads to reporter activation and whether therapeutic intervention modulates reporters' expression. We anticipate the reporter strategy could be of great value in developing treatments for a range of degenerative disorders.

Cells must rapidly adapt to changes in nutrient conditions through responsive signalling cascades to maintain homeostasis. One of these adaptive pathways results in the post-translational modification of proteins by O-GlcNAc. O-GlcNAc modifies thousands of nuclear and cytoplasmic proteins in response to nutrient availability through the hexosamine biosynthetic pathway. O-GlcNAc is highly dynamic and can be added and removed from proteins multiple times throughout their life cycle, setting it up to be an ideal regulator of cellular processes in response to metabolic changes. Here, we describe the link between cellular metabolism and O-GlcNAc, and we explore O-GlcNAc's role in regulating cellular processes in response to nutrient levels. Specifically, we discuss the mechanisms of elevated O-GlcNAc levels in contributing to diabetes and cancer, as well as the role of decreased O-GlcNAc levels in neurodegeneration. These studies form a foundational understanding of aberrant O-GlcNAc in human disease and provide an opportunity to further improve disease identification and treatment.

The switch/sucrose non-fermentable (SWI/SNF) subfamily are evolutionarily conserved, ATP-dependent chromatin-remodelling complexes that alter nucleosome position and regulate a spectrum of nuclear processes, including gene expression, DNA replication, DNA damage repair, genome stability and tumour suppression. These complexes, through their ATP-dependent chromatin remodelling, contribute to the dynamic regulation of genetic information and the maintenance of cellular processes essential for normal cellular function and overall genomic integrity. Mutations in SWI/SNF subunits are detected in 25% of human malignancies, indicating that efficient functioning of this complex is required to prevent tumourigenesis in diverse tissues. During development, SWI/SNF subunits help establish and maintain gene expression patterns essential for proper cellular identity and function, including maintenance of lineage-specific enhancers. Moreover, specific molecular signatures associated with SWI/SNF mutations, including disruption of SWI/SNF activity at enhancers, evasion of G0 cell cycle arrest, induction of cellular plasticity through pro-oncogene activation and Polycomb group (PcG) complex antagonism, are linked to the initiation and progression of carcinogenesis. Here, we review the molecular insights into the aetiology of human malignancies driven by disruption of the SWI/SNF complex and correlate these mechanisms to their developmental functions. Finally, we discuss the therapeutic potential of targeting SWI/SNF subunits in cancer.

In this study, we develop an in silico model of a neuron's behaviour under demyelination caused by a cytokine storm to investigate the effects of viral infections in the brain. We use a comprehensive model to measure how cytokine-induced demyelination affects the propagation of action potential (AP) signals within a neuron. We analysed the effects of neuron-neuron communications by applying information and communication theory at different levels of demyelination. Our simulations demonstrate that virus-induced degeneration can play a role in the signal power and spiking rate, which compromise the propagation and processing of information between neurons. We propose a transfer function to model the weakening effects on the AP. Our results show that demyelination induced by a cytokine storm not only degrades the signal but also impairs its propagation within the axon. Our proposed in silico model can analyse virus-induced neurodegeneration and enhance our understanding of virus-induced demyelination.

Gregarines are a large and diverse subgroup of Apicomplexa, a lineage of obligate animal symbionts including pathogens such as Plasmodium, the malaria parasite. Unlike Plasmodium, however, gregarines are poorly studied, despite the fact that as early-branching apicomplexans they are crucial to our understanding of the origin and evolution of all apicomplexans and their parasitic lifestyle. Exemplifying this, the earliest branch of gregarines, the archigregarines, are particularly poorly studied: around 80 species have been described from marine invertebrates, but almost all of them were assigned to a single genus, Selenidium. Most are known only from light micrographs and largely unresolved rDNA phylogenies, where they exhibit a great deal of sequence variation, and fall into four subclades. To resolve the relationships within archigregarines, we sequenced 12 single-cell transcriptomes from species representing all four known subclades, as well as one blastogregarine (which frequently branch with Selenidium). A 190-gene phylogenomic tree confirmed four maximally supported individual clades of archigregarines and blastogregarines. These clades are discrete and distantly related, and also correlate with host identity. We propose the establishment of three novel genera of archigregarines to reflect their phylogenetic diversity and host range, and nine novel species isolated from a range of marine invertebrates.

Calmodulin (CaM) is a ubiquitous calcium-sensitive messenger in eukaryotic cells. It was previously shown that CaM possesses an affinity for diverse lipid moieties, including those found on CaM-binding proteins. These facts, together with our observation that CaM accumulates in membrane-rich protrusions of HeLa cells upon increased cytosolic calcium, motivated us to perform a systematic search for unmediated CaM interactions with model lipid membranes mimicking the cytosolic leaflet of plasma membranes. A range of experimental techniques and molecular dynamics simulations prove unambiguously that CaM interacts with lipid bilayers in the presence of calcium ions. The lipids phosphatidylserine (PS) and phosphatidylethanolamine (PE) hold the key to CaM-membrane interactions. Calcium induces an essential conformational rearrangement of CaM, but calcium binding to the headgroup of PS also neutralizes the membrane negative surface charge. More intriguingly, PE plays a dual role-it not only forms hydrogen bonds with CaM, but also destabilizes the lipid bilayer increasing the exposure of hydrophobic acyl chains to the interacting proteins. Our findings suggest that upon increased intracellular calcium concentration, CaM and the cytosolic leaflet of cellular membranes can be functionally connected.

Cilia are antenna-like organelles protruding from the surface of many cell types in the human body. Defects in ciliary structure or function often lead to diseases that are collectively called ciliopathies. Cilia and flagella-associated protein 410 (CFAP410) localizes at the basal body of cilia/flagella and plays essential roles in ciliogenesis, neuronal development and DNA damage repair. It remains unknown how its specific basal body location is achieved. Multiple single amino acid mutations in CFAP410 have been identified in patients with various ciliopathies. One of the mutations, L224P, is located in the C-terminal domain (CTD) of human CFAP410 and causes severe spondylometaphyseal dysplasia, axial (SMDAX). However, the molecular mechanism for how the mutation causes the disorder remains unclear. Here, we report our structural studies on the CTD of CFAP410 from three distantly related organisms, Homo sapiens, Trypanosoma brucei and Chlamydomonas reinhardtii. The crystal structures reveal that the three proteins all adopt the same conformation as a tetrameric helical bundle. Our work further demonstrates that the tetrameric assembly of the CTD is essential for the correct localization of CFAP410 in T. brucei, as the L224P mutation that disassembles the tetramer disrupts its basal body localization. Taken together, our studies reveal that the basal body localization of CFAP410 is controlled by the CTD and provide a mechanistic explanation for how the mutation L224P in CFAP410 causes ciliopathies in humans.

Nutrition and resilience are linked, though it is not yet clear how diet confers stress resistance or the breadth of stressors that it can protect against. We have previously shown that transiently restricting an essential amino acid can protect Drosophila melanogaster against nicotine poisoning. Here, we sought to characterize the nature of this dietary-mediated protection and determine whether it was sex, amino acid and/or nicotine specific. When we compared between sexes, we found that isoleucine deprivation increases female, but not male, nicotine resistance. Surprisingly, we found that this protection afforded to females was not replicated by dietary protein restriction and was instead specific to individual amino acid restriction. To understand whether these beneficial effects of diet were specific to nicotine or were generalizable across stressors, we pre-treated flies with amino acid restriction diets and exposed them to other types of stress. We found that some of the diets that protected against nicotine also protected against oxidative and starvation stress, and improved survival following cold shock. Interestingly, we found that a diet lacking isoleucine was the only diet to protect against all these stressors. These data point to isoleucine as a critical determinant of robustness in the face of environmental challenges.