DNA damage

Impaired repair of DNA damage is associated with autistic-like traits in rats prenatally exposed to valproic acid

Prenatal exposure to the antiepileptic and mood stabilizer valproic acid (VPA) is an environmental risk factor for autism spectrum disorders (ASD), although recent epidemiological studies show that the public awareness of this association is still limited. Based on the clinical findings, prenatal VPA exposure in rodents is a widely used preclinical model of ASD. However, there is limited information about the precise biochemical mechanisms underlying the link between ASD and VPA.

p53-sensitive epileptic behavior and inflammation in Ft1 hypomorphic mice

Epilepsy is a complex clinical condition characterized by repeated spontaneous seizures. Seizures have been linked to multiple drivers including DNA damage accumulation. Investigation of epilepsy physiopathology in humans imposes ethical and practical limitations, for this reason model systems are mostly preferred. Among animal models, mouse mutants are particularly valuable since they allow conjoint behavioral, organismal, and genetic analyses.

Protective role of vitamin B6 (PLP) against DNA damage in Drosophila models of type 2 diabetes

Growing evidence shows that improper intake of vitamin B6 increases cancer risk and several studies indicate that diabetic patients have a higher risk of developing tumors. We previously demonstrated that in Drosophila the deficiency of Pyridoxal 5' phosphate (PLP), the active form of vitamin B6, causes chromosome aberrations (CABs), one of cancer prerequisites, and increases hemolymph glucose content. Starting from these data we asked if it was possible to provide a link between the aforementioned studies. Thus, we tested the effect of low PLP levels on DNA integrity in diabetic cells.

Genomic instability and DNA replication defects in progeroid syndromes

Progeroid syndromes induced by mutations in lamin A or in its interactors – named progeroid laminopathies – are model systems for the dissection of the molecular pathways causing physio- logical and premature aging. A large amount of data, based mainly on the Hutchinson Gilford Progeria syndrome (HGPS), one of the best characterized progeroid laminopathy, has highlighted the role of lamins in multiple DNA activities, including replication, repair, chromatin organization and telomere function.

Activation of M2 muscarinic acetylcholine receptors by a hybrid agonist enhances cytotoxic effects in GB7 glioblastoma cancer stem cells

In previous studies, we found that the orthosteric muscarinic agonist arecaidine propargyl ester (APE) (100 μM) induced a decreased cell proliferation and severe apoptosis in glioblastoma cancer stem cells (GSCs). In this report, we have investigated the effects mediated by hybrid (orthosteric/allosteric) muscarinic agonists P-6-Iper and N-8-Iper on GSCs survival. At variance with APE, the agonist N-8-Iper inhibited cell growth in a dose dependent manner and also impaired cell survival at low doses.

Inducible SMARCAL1 knockdown in iPSC reveals a link between replication stress and altered expression of master differentiation genes

The Schimke immuno-osseous dysplasia is an autosomal recessive genetic osteochondrodysplasia characterized by dysmorphism, spondyloepiphyseal dysplasia, nephrotic syndrome and frequently T cell immunodeficiency. Several hypotheses have been proposed to explain pathophysiology of the disease, however, the mechanism by which SMARCAL1 mutations cause the syndrome is elusive. Here, we generated a conditional SMARCAL1 knockdown model in iPSCs to mimic conditions associated with the severe form the disease.

JARID1B expression and its function in DNA damage repair are tightly regulated by miRNAs in breast cancer

JARID1B/KDM5B histone demethylase's mRNA is markedly over-expressed in breast cancer tissues and cell lines and the protein has been shown to have a prominent role in cancer cell proliferation and DNA repair. On the other hand, its post-transcriptional regulation in cancer cells remains elusive. We performed a computational analysis of transcriptomic data from a set of 103 breast cancer patients which, along with JARID1B up-regulation, showed a strong down-regulation of two miRNA, mir-381 and mir-486, potentially targeting its mRNA.

A genotoxicity study on Talitrus saltator (Crustacea, Amphipoda) exposed to lead and benzo(a)pyrene

Sandy beaches are ecosystems often subjected to a variety of pollution sources, including heavy metals and polycyclic aromatic hydrocarbons, largely due to improper human activities. The sandhopper Talitrus saltator s. l. (Montagu, 1808) typically lives on supralittoral shores where it plays an important ecological role. The purpose of this study was to investigate DNA damage levels on hemocytes of T. saltator by means of the Comet assay. Firstly, we tested the sensitivity and reproducibility of the Comet assay on hemocytes of T.

Citron Kinase Deficiency Leads to Chromosomal Instability and TP53-Sensitive Microcephaly

Mutations in citron (CIT), leading to loss or inactivation of the citron kinase protein (CITK), cause primary microcephaly in humans and rodents, associated with cytokinesis failure and apoptosis in neural progenitors. We show that CITK loss induces DNA damage accumulation and chromosomal instability in both mammals and Drosophila. CITK-deficient cells display "spontaneous" DNA damage, increased sensitivity to ionizing radiation, and defective recovery from radiation-induced DNA lesions. In CITK-deficient cells, DNA double-strand breaks increase independently of cytokinesis failure.

The Drosophila telomere-capping protein Verrocchio binds single-stranded DNA and protects telomeres from DNA damage response

Drosophila telomeres are sequence-independent structures maintained by transposition to chromosome ends of three specialized retroelements rather than by telomerase activity. Fly telomeres are protected by the terminin complex that includes the HOAP, HipHop, Moi and Ver proteins. These are fast evolving, non-conserved proteins that localize and function exclusively at telomeres, protecting them from fusion events. We have previously suggested that terminin is the functional analogue of shelterin, the multi-protein complex that protects human telomeres.

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