Biology subjects

Severino, A.

Publications and source records attributed to Severino, A..

6 recordsLinked to original sources

bioRxiv2026

A peripherally restricted cannabinoid 1 receptor agonist provides analgesic benefit from neuropathic pain and a lack of addiction-related behavior

IntroductionCannabis is increasingly used for pain management, with many patients reporting relief from chronic pain that did not respond to conventional treatments. However, cannabis is also associated with unwanted side effects including psychomimetic effects and the potential of developing a cannabis use disorder. To circumvent the central nervous system effects, we investigated whether a peripherally restricted cannabinoid receptor (CB1) agonist, PrNMI [(4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3yl]ethyl}morpholine] attenuated pain hypersensitivity associated with nerve injury and profiled its abuse potential. Materials and MethodsMice with chronic constriction injury (CCI) of the sciatic nerve developed hypersensitivity to mechanical stimulation. Paw withdrawal thresholds were assessed following administration of PrNMI (i.p. 0.3 mg/kg and 0.6 mg/kg) or vehicle in CCI and sham mice. The conditioned place preference model was used to measure drug-reward to 0.6 mg/kg i.p. PrNMI in CCI and sham-injury control animals. We further assessed abuse potential to determine if PrNMI (0.5 mg/kg) would reinstate drug-seeking behavior in mice trained to self-administer intravenous fentanyl (10 g/kg/infusion). ResultsPrNMI administration transiently increased paw withdrawal thresholds in mice with CCI-induced allodynia in a dose-dependent manner. PrNMI conditioning did not produce a conditioned place preference in mice with either CCI or sham injury. Mice who had learned to self-administer fentanyl and went through extinction training did not reinstate drug-seeking behavior when administered PrNMI. DiscussionThe systemic CB1 receptor agonist PrNMI demonstrated analgesic benefit in alleviating mechanical allodynia associated with chronic constriction injury of the sciatic nerve without increasing addiction related behaviors associated with the establishment of addiction.

neuroscience↗

bioRxiv2026

Characterizing Highly Conserved Fragments in 3'UTRs via Computational and Transfer Learning Approaches

3 untranslated regions (3 UTRs) serve as regulatory platforms that modulate translation, mRNA localization, and stability through the binding of regulators, such as RNA-binding proteins (RBPs) and miRNAs, in a sequence-specific manner. These vital binding sites are often identified through orthologous regions among species. A separate but related discovery is the ultraconserved elements (UCEs) detected in human, rat, and mouse genomes two decades ago. However, our knowledge about their functions is limited. Perplexingly, alterations in UCEs in mouse embryos can still produce viable progeny with no observable phenotypic differences. The majority of UCEs are non-coding, though [~]8% are located in the 3UTRs. Given the importance of 3UTRs in gene regulation, we use a computational approach to identify highly conserved fragments (CFs) in 3UTRs across diverse mammals, applying criteria appropriate for 3UTRs (250 bp and 290% identity). Results show that they are not composed of simple repeats or low-complexity regions common to mammalian genomes. Using a transformer-based foundational genomic model, CFs are characterized as A and T-rich and distinguishable from the 3UTR background. 36 human CFs from 25 genes are significantly depleted in variations in humans. They are enriched in neuronal tissues and play roles in neurodevelopment and RNA processing, mediated by RBPs and miRNAs. Our findings expand on existing studies that attribute UCEs primarily to enhancer function, suggesting a new path to explore the biological roles of UCEs in 3UTRs. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=139 SRC="FIGDIR/small/700376v1_ufig1.gif" ALT="Figure 1000"> View larger version (30K): org.highwire.dtl.DTLVardef@39727forg.highwire.dtl.DTLVardef@18c0374org.highwire.dtl.DTLVardef@136b784org.highwire.dtl.DTLVardef@14a5146_HPS_FORMAT_FIGEXP M_FIG C_FIG Created in BioRender. Ho, E. (2026) https://BioRender.com/dcyrx5f

genomics↗

bioRxiv2025

Cell type specific CaMKII activation patterns revealed by CaMKAR, a bioactivity reporter deployable in living cells

An accurate and precise mechanism for measuring CaMKII activity in living cells is invaluable in the search for effective and targeted CaMKII-based therapeutics. Here, we employ our recently published CaMKII Activity Reporter (CaMKAR) biosensor in order to investigate the spatiotemporal dynamics of CaMKII activation in three different types of cells - cardiac myocytes, skeletal myocytes, and neurons. In doing so, we found a greater rate of CaMKII activation in skeletal muscle compared to cardiac muscle and also delineated CaMKARs ability to measure discrete CaMKII activation events in the presence of individual action potentials. By modifying the original CaMKAR sequence, we generated sensors that can be localized to subcellular compartments and thereby preferentially detect the activity of specific spatially-distributed CaMKII isoforms. Finally, we utilized the live-cell data to generate mathematical models of CaMKII activation kinetics, both as an integrated function across multiple calcium transients and as discrete on-off events following individual depolarizations. By furthering our understanding of CaMKII activity profiles across cell types and within subcellular compartments, we hope to support development of CaMKII inhibitors that are optimally precise and potent.

molecular biology↗

bioRxiv2024

Engineering the Marine Pseudoalteromonas haloplanktis TAC125 via pMEGA Plasmid Targeted Curing Using PTasRNA Technology

Marine bacteria that have adapted to thrive in extreme environments, such as Pseudoalteromonas haloplanktis TAC125 (PhTAC125), offer a unique biotechnological potential. The discovery of an endogenous megaplasmid (pMEGA) raised questions about its metabolic impact and functional role in this strain. This study aimed at streamlining the host genetic background by curing PhTAC125 from the pMEGA plasmid using a sequential genetic approach. We combined homologous recombination by exploiting a suicide vector with the PTasRNA gene silencing technology to interfere with pMEGA replication machinery. This approach led to the construction of the novel PhTAC125 KrPL2 strain, cured from the pMEGA plasmid, which exhibited no significant differences in the growth behaviour, though showcasing enhanced resistance to oxidative stress and a reduced capability of biofilm formation. These findings represent a significant achievement for understanding of the role of pMEGA plasmid and for the biotechnological applications of PhTAC125 in recombinant protein production. This opens up the possibility to exploit pMEGA valuable genetic elements and further advancing the genetic tools for PhTAC125.

microbiology↗

bioRxiv2024

SGLT2 inhibitors protect against diabetic cardiomyopathy and atrial fibrillation through a CaMKII independent mechanism

Ca2+/calmodulin-dependent protein kinase II (CaMKII) has been implicated as an important mediator of the increasingly evident cardioprotective benefits exerted by sodium- glucose transport protein 2 channel inhibitors (SGLT2i). However, the exact nature of the relationship between CaMKII and SGLT2i remains unclear. Here, we find that empagliflozin but not dapagliflozin attenuated susceptibility to atrial fibrillation (AF) in a type 2 diabetic (T2D) mouse model. However, both empagliflozin and dapagliflozin protected from diabetic cardiomyopathy in T2D mice. We then used real-time microscopy of neonatal rat ventricular cardiomyocytes (NRVMs) with the CaMKII biosensor - CaMKAR to demonstrate that direct inhibition of CaMKII is not essential for the effects of SGLT2i in these cells. Therefore, we conclude that the benefits of SGLT2i in heart disease likely occur through indirect modulation of CaMKII activity, or possibly through an alternative pathway altogether.

molecular biology↗

bioRxiv2024

Universal Cold RNA Phase Transitions

RNAs diversity of structures and functions impacts all life forms since primordia. We use calorimetric force spectroscopy to investigate RNA folding landscapes in previously unexplored low-temperature conditions. We find that Watson-Crick RNA hairpins, the most basic secondary structure elements, undergo a glass-like transition below TG [~] 20{degrees}C where the heat capacity abruptly changes and the RNA folds into a diversity of misfolded structures. We hypothesize that an altered RNA biochemistry, determined by sequence-independent ribose-water interactions, outweighs sequence-dependent base pairing. The ubiquitous ribose-water interactions lead to universal RNA phase transitions below TG, such as maximum stability at TS [~] 5{degrees}C where water density is maximum, and cold denaturation at TC [~] -50{degrees}C. RNA cold biochemistry may have a profound impact on RNA function and evolution.

biophysics↗