FUS Mislocalization Rewires a Cortical Gene Network to Drive Cognitive and Behavioral Impairment in ALS.

Cognitive and behavioral impairment affects up to half of individuals with amyotrophic lateral sclerosis (ALS), but their molecular origin remains unresolved. Here, we identify mislocalization of the RNA-binding protein FUS in cortical neurons as a defining feature in ALS patients with cognitive impairment (ALS-ci). Selective mislocalization of FUS in adult cortical projection neurons in mice is sufficient to trigger ALS-ci- and ALS with behavioral impairment (ALS-bi)-like phenotypes, including deficits in sociability, and neurodegeneration.

PIK3C2A-Related Clinical Phenotype and Cellular Charaterization Linked to Functional SHH Primary Cilia Defect.

PIK3C2A is a member of the class II phosphatidylinositol-3-kinases (PI3K) family that catalyzes the phosphorylation of phosphatidylinositol (PI) into PI(3)P and of PI(4)P into PI(3,4)P2. These second messenger lipids regulate a wide range of downstream signaling pathways involved in many physiological functions and cellular processes, including cell proliferation, growth, survival, motility, and metabolism. PIK3C2A is also involved in the regulation of primary cilia formation and maintenance and in the regulation of receptor-mediated endocytosis at the base of the cilium.

CREB3 gain of function variants protect against ALS.

Amyotrophic lateral sclerosis (ALS) is a fatal and rapidly evolving neurodegenerative disease arising from the loss of glutamatergic corticospinal neurons (CSN) and cholinergic motoneurons (MN). Here, we performed comparative cross-species transcriptomics of CSN using published snRNA-seq data from the motor cortex of ALS and control postmortem tissues, and performed longitudinal RNA-seq on CSN purified from male Sod1 mice. We report that CSN undergo ER stress and altered mRNA translation, and identify the transcription factor CREB3 and its regulatory network as a resilience marker of ALS, not only amongst vulnerable neuronal populations, but across all neuronal populations as well as other cell types.

Experimental myositis: an optimised version of C-protein-induced myositis.

Introduction: Inflammatory myopathies (IM) are a group of severe autoimmune diseases, sharing some similarities, whose cause is unknown and treatment is empirical.While C-protein-induced myositis (CIM), the most currently used mouse model of IM, has removed some roadblocks to understand and improve the treatment of IM, it has only been partially characterised and its generation limited by poor reproducibility. This study aimed at optimising the generation and the characterisation of CIM.

A Snake Toxin Derivative for Treatment of Hyponatremia and Polycystic Kidney Diseases.

Key Points: MQ232, a disulfide-bond reticulated peptide derived from a natural snake toxin, was optimized as a new aquaretic drug candidate. MQ232 showed very low acute and chronic toxicity in rat and a biodistribution in mice strongly in favor of the kidney organs. MQ232 induced a sole aquaretic effect and demonstrated high activities on hyponatremia and polycystic kidney disease models.

Cortical hyperexcitability in mouse models and patients with amyotrophic lateral sclerosis is linked to noradrenaline deficiency.

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, characterized by the death of upper (UMN) and lower motor neurons (LMN) in the motor cortex, brainstem, and spinal cord. Despite decades of research, ALS remains incurable, challenging to diagnose, and of extremely rapid progression. A unifying feature of sporadic and familial forms of ALS is cortical hyperexcitability, which precedes symptom onset, negatively correlates with survival, and is sufficient to trigger neurodegeneration in rodents.

A synthetic delivery vector for mucosal vaccination.

The success of mRNA-based vaccines during the Covid-19 pandemic has highlighted the value of this new platform for vaccine development against infectious disease. However, the CD8 T cell response remains modest with mRNA vaccines, and these do not induce mucosal immunity, which would be needed to prevent viral spread in the healthy population. To address this drawback, we developed a dendritic cell targeting mucosal vaccination vector, the homopentameric STxB.

Engineered Synthetic STxB for Enhanced Cytosolic Delivery.

Many molecular targets for cancer therapy are located in the cytosol. Therapeutic macromolecules are generally not able to spontaneously translocate across membranes to reach these cytosolic targets. Therefore a strong need exists for tools that enhance cytosolic delivery.

From a Cone Snail Toxin to a Competitive MC4R Antagonist.

The melanocortin 4 receptor (MC4R) plays a role in energy homeostasis and represents a target for treating energy balance disorders. For decades, synthetic ligands have been derived from MC4R endogenous agonists and antagonists, such as setmelanotide used to treat rare forms of genetic obesity. Recently, animal venoms have demonstrated their capacity to provide melanocortin ligands with toxins from a scorpion and a spider.

Cytoplasmic FUS triggers early behavioral alterations linked to cortical neuronal hyperactivity and inhibitory synaptic defects.

Gene mutations causing cytoplasmic mislocalization of the RNA-binding protein FUS lead to severe forms of amyotrophic lateral sclerosis (ALS). Cytoplasmic accumulation of FUS is also observed in other diseases, with unknown consequences. Here, we show that cytoplasmic mislocalization of FUS drives behavioral abnormalities in knock-in mice, including locomotor hyperactivity and alterations in social interactions, in the absence of widespread neuronal loss.

Mambalgin-1 pain-relieving peptide locks the hinge between α4 and α5 helices to inhibit rat acid-sensing ion channel 1a.

Acid-sensing ion channels (ASICs) are proton-gated cationic channels involved in pain and other processes, underscoring the potential therapeutic value of specific inhibitors such as the three-finger toxin mambalgin-1 (Mamb-1) from snake venom. A low-resolution structure of the human-ASIC1a/Mamb-1 complex obtained by cryo-electron microscopy has been recently reported, implementing the structure of the chicken-ASIC1/Mamb-1 complex previously published. Here we combine structure-activity relationship of both the rat ASIC1a channel and the Mamb-1 toxin with a molecular dynamics simulation to obtain a detailed picture at the level of side-chain interactions of the binding of Mamb-1 on rat ASIC1a channels and of its inhibition mechanism.

A snake toxin as a theranostic agent for the type 2 vasopressin receptor.

MQ1, a snake toxin which targets with high nanomolar affinity and absolute selectivity for the type 2 vasopressin receptor (V2R), is a drug candidate for renal diseases and a molecular probe for imaging cells or organs expressing V2R. MQ1's pharmacological properties were characterized and applied to a rat model of hyponatremia. Its PK/PD parameters were determined as well as its therapeutic index.

Amphiphysin 2 modulation rescues myotubular myopathy and prevents focal adhesion defects in mice.

Centronuclear myopathies (CNMs) are severe diseases characterized by muscle weakness and myofiber atrophy. Currently, there are no approved treatments for these disorders. Mutations in the phosphoinositide 3-phosphatase myotubularin (MTM1) are responsible for X-linked CNM (XLCNM), also called myotubular myopathy, whereas mutations in the membrane remodeling Bin/amphiphysin/Rvs protein amphiphysin 2 [bridging integrator 1 (BIN1)] are responsible for an autosomal form of the disease.

STIM1 over-activation generates a multi-systemic phenotype affecting the skeletal muscle, spleen, eye, skin, bones and immune system in mice.

Strict regulation of Ca2+ homeostasis is essential for normal cellular physiology. Store-operated Ca2+ entry (SOCE) is a major mechanism controlling basal Ca2+ levels and intracellular Ca2+ store refilling, and abnormal SOCE severely impacts on human health. Overactive SOCE results in excessive extracellular Ca2+ entry due to dominant STIM1 or ORAI1 mutations and has been associated with tubular aggregate myopathy (TAM) and Stormorken syndrome (STRMK).

Reducing dynamin 2 (DNM2) rescues -related dominant centronuclear myopathy.

Centronuclear myopathies (CNM) are a group of severe muscle diseases for which no effective therapy is currently available. We have previously shown that reduction of the large GTPase DNM2 in a mouse model of the X-linked form, due to loss of myotubularin phosphatase MTM1, prevents the development of the skeletal muscle pathophysiology. As is mutated in autosomal dominant forms, here we tested whether DNM2 reduction can rescue -related CNM in a knock-in mouse harboring the p.

A Method for Parasagittal Sectioning for Neuroanatomical Quantification of Brain Structures in the Adult Mouse.

In this article, we present a standardized protocol for fast and robust neuroanatomical phenotyping of the adult mouse brain, which complements a previously published article (doi: 10.1002/cpmo.12) in Current Protocols in Mouse Biology.

Late-Stage Isotopic Carbon Labeling of Pharmaceutically Relevant Cyclic Ureas Directly from CO.

A robust, click-chemistry-inspired procedure for radiolabeling of cyclic ureas was developed. This protocol, suitable for all carbon isotopes ( C, C, C), is based on the direct functionalization of carbon dioxide: the universal building block for carbon radiolabeling. The strategy is operationally simple and reproducible in different radiochemistry centers, exhibits remarkably wide substrate scope with short reaction times, and demonstrates superior reactivity as compared to previously reported systems.

Expression of the neuropathy-associated MTMR2 gene rescues MTM1-associated myopathy.

Myotubularins (MTMs) are active or dead phosphoinositides phosphatases defining a large protein family conserved through evolution and implicated in different neuromuscular diseases. Loss-of-function mutations in MTM1 cause the severe congenital myopathy called myotubular myopathy (or X-linked centronuclear myopathy) while mutations in the MTM1-related protein MTMR2 cause a recessive Charcot-Marie-Tooth peripheral neuropathy. Here we aimed to determine the functional specificity and redundancy of MTM1 and MTMR2, and to assess their abilities to compensate for a potential therapeutic strategy.

Coactivators and general transcription factors have two distinct dynamic populations dependent on transcription.

SAGA and ATAC are two distinct chromatin modifying co-activator complexes with distinct enzymatic activities involved in RNA polymerase II (Pol II) transcription regulation. To investigate the mobility of co-activator complexes and general transcription factors in live-cell nuclei, we performed imaging experiments based on photobleaching. SAGA and ATAC, but also two general transcription factors (TFIID and TFIIB), were highly dynamic, exhibiting mainly transient associations with chromatin, contrary to Pol II, which formed more stable chromatin interactions.

The three-finger toxin fold: a multifunctional structural scaffold able to modulate cholinergic functions.

Three-finger fold toxins are miniproteins frequently found in Elapidae snake venoms. This fold is characterized by three distinct loops rich in β-strands and emerging from a dense, globular core reticulated by four highly conserved disulfide bridges. The number and diversity of receptors, channels, and enzymes identified as targets of three-finger fold toxins is increasing continuously.

A Theranostic Agent Combining a Two-Photon-Absorbing Photosensitizer for Photodynamic Therapy and a Gadolinium(III) Complex for MRI Detection.

The convergent synthesis and characterization of a potential theranostic agent, [DPP-ZnP-GdDOTA](-), which combines a diketopyrrolopyrrole-porphyrin component DPP-ZnP as a two-photon photosensitizer for photodynamic therapy (PDT) with a gadolinium(III) DOTA complex as a magnetic resonance imaging probe, is presented. [DPP-ZnP-GdDOTA](-) has a remarkably high longitudinal water proton relaxivity (19.94 mm(-1)  s(-1) at 20 MHz and 25 °C) for a monohydrated molecular system of this size.