Biology subjects

Cozzolino, M.

Publications and source records attributed to Cozzolino, M..

4 recordsLinked to original sources

bioRxiv2026

Interplay Between Retroviral Element De-repression and Wnt/β-Catenin Pathway in Cellular Models of Parkinson's Disease

Parkinsons disease (PD) is characterized by progressive dopaminergic neurodegeneration driven by complex interactions among oxidative stress, impaired survival signaling, and protein homeostasis disruption. Emerging evidence suggests that endogenous retroelements, including human endogenous retrovirus K (HERV-K), may contribute to neurodegenerative processes; however, their role in PD remains poorly defined. Here, we investigated whether dopaminergic neurotoxic stress induces HERV-K activation and whether modulation of pro-survival signaling pathways influences this response in PD-relevant cellular models. Using undifferentiated SHSY5Y cells and neuron-like retinoic acid-differentiated SHSY5Y cells, we show that exposure to the dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA) induces a rapid and robust transcriptional de-repression of HERV-K Env gene. HERV-K activation occurs early after toxin exposure, scales with the intensity of the insult, and is associated with alterations in oxidative stress defenses, survival signaling pathways, and protein homeostasis. Notably, 6-OHDA treatment promotes the accumulation and cytoplasmic mislocalization of phosphorylated TAR DNA-binding protein 43 (pTDP-43), a pathological feature linked to neurodegenerative proteinopathies. Pharmacological modulation of the Wnt/{beta}-catenin pathway by the natriuretic peptide atrial natriuretic peptide (ANP) significantly attenuates neurotoxin-induced HERV-K activation, restores oxidative stress-related and survival signaling markers, and limits pTDP-43 accumulation and mislocalization. These findings indicate that reinforcement of Wnt/{beta}-catenin dependent protective pathways constrains stress-driven HERV-K de-repression and associated molecular alterations. Overall, this study identifies HERV-K activation as an early stress-responsive feature in PD-like cellular models and supports the existence of a functional interplay between retroelement regulation, survival signaling, and protein homeostasis. Modulation of Wnt/{beta}-catenin signaling may represent a strategy to limit retroelement-associated pathological responses in PD.

neuroscience↗

bioRxiv2024

Cytoplasmic accumulation of a splice variant of hnRNP A2/B1 contributes to FUS-associated toxicity in a mouse model of ALS

Genetic and experimental findings point to a crucial role of RNA dysfunction in the pathogenesis of Amyotrophic Lateral Sclerosis (ALS). Evidence suggests that mutations in RBPs such as FUS, a gene associated with ALS, affect the regulation of alternative splicing. We have previously shown that the overexpression of wild-type FUS in mice, a condition that induces ALS-like phenotypes, impacts the splicing of hnRNP A2/B1, a protein with key roles in RNA metabolism, suggesting that a pathological connection between FUS and hnRNP A2/B1 might promote FUS-associated toxicity. Here we report that the expression and distribution of different hnRNP A2/B1 splice variants are modified in the affected tissues of mice overexpressing wild-type FUS. Notably, degenerating motor neurons are characterized by the cytoplasmic accumulation of splice variants of hnRNP A2/B1 lacking exon 9 (hnRNP A2b/B1b). In vitro studies show that exon 9 skipping affects the nucleocytoplasmic distribution of hnRNP A2/B1, promoting its localization into stress granules (SGs), and demonstrate that cytoplasmic localization is the primary driver of hnRNP A2b recruitment into SGs and cell toxicity. Finally, boosting exon 9 skipping using splicing switching oligonucleotides exacerbates disease phenotypes in wild-type FUS mice. Altogether, these findings reveal that alterations of the nucleocytoplasmic distribution of hnRNP A2/B1, driven by FUS-induced splicing changes, likely contribute to motor neuron degeneration in ALS.

neuroscience↗

bioRxiv2024

DNA damage response defects induced by the formation of TDP-43 and mutant FUS cytoplasmic inclusions and their pharmacological rescue.

Formation of cytoplasmic inclusions (CIs) of TDP-43 and FUS, along with DNA damage accumulation, is a hallmark of affected motor neurons in Amyotrophic Lateral Sclerosis (ALS). However, the impact of CIs on DNA damage response (DDR) and repair in this pathology remains unprobed. Here, we show that CIs of TDP-43 and FUSP525L, co-localizing with stress granules, lead to a dysfunctional DDR activation associated with physical DNA breakage. Inhibition of the activity of the DDR kinase ATM, but not of ATR, abolishes DDR signaling, indicating that DNA double-strand breaks (DSBs) are the primary source of DDR activation. In addition, cells with TDP-43 and FUSP525L CIs exhibit reduced DNA damage-induced RNA synthesis at DSBs. We previously showed that the two endoribonucleases DROSHA and DICER, also known to interact with TDP-43 and FUS during small RNA processing, contribute to DDR signaling at DSBs. Treatment with enoxacin, which stimulates DDR and repair by boosting the enzymatic activity of DICER, restores a proficient DDR and reduces DNA damage accumulation in cultured cells with CIs and in vivo in a murine model of ALS. In Drosophila melanogaster, Dicer-2 overexpression rescues TDP-43-mediated retinal degeneration. In summary, our results indicate that the harmful effects caused by TDP-43 and FUS proteinopathies include genotoxic stress and that the pharmacological stimulation of the DNA damage signaling and repair counteracts it.

molecular biology↗

bioRxiv2018

Enigma at the nanoscale: can the NPC act as an intrinsic reporter for isotropic expansion microscopy?

Expansion microscopy is a super-resolution method that allows expanding uniformly biological samples, by increasing the relative distances among fluorescent molecules labeling specific components. The main \"enigma\" regarding this approach is given by the isotropic behavior at the nanoscale. The present study aims to determine the robustness of such a technique, quantifying the expansion parameters i.e. scale factor, isotropy, uniformity. Our focus is on the nuclear pore complex (NPC), as well-known nanoscale component endowed of a preserved and symmetrical structure localized on the nuclear envelope. Here, we show that Nup153 is a good reporter to quantitatively address the isotropy of the expansion process. The quantitative analysis carried out on NPCs, at different spatial scales, allows concluding that expansion microscopy can be used at the nanoscale with a uniform accuracy in the range of 20 nm. In addition, it is an excellent method for structural studies of macromolecular complexes.

biophysics↗