Crosstalk between DNA damage and cGAS-STING immune pathway drives neuroinflammation and dopaminergic neurodegeneration in Parkinson's disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder marked by substantial degeneration of dopaminergic neurons in the substantia nigra and dopamine depletion in the striatum, leading to debilitating motor and non-motor impairments. Recent studies provide clues on the pathogenic role of DNA damage in age-related neurodegenerative diseases, but the molecular mechanisms of DNA damage response in PD remain poorly understood. We found that the accumulation of DNA double-strand breaks (DDSBs), and/or DNA repair deficits, are key in the pathogenesis of PD and drives cyclic GMP-AMP synthase (cGAS) and stimulator of interferon genes (STING) immune regulatory pathway, contributing to neuroinflammation and dopaminergic neurodegeneration in human postmortem PD and non-PD brains as well as in experimental models of PD.

An Overview of UBTF Neuroregression Syndrome.

Recently, a recurrent de novo dominant mutation in (c.628G>A, p.Glu210Lys; E210K) was identified as the cause of a neurological disorder which has been named UBTF Neuroregression Syndrome (UNS), or Childhood-Onset Neurodegeneration with Brain Atrophy (CONDBA).

Behavioral and molecular effects of Ubtf knockout and knockdown in mice.

The UBTF E210K neuroregression syndrome is caused by de novo dominant mutations in UBTF (NM_014233.3:c.628G > A, p.

Ribosomal DNA promoter recognition is determined in vivo by cooperation between UBTF1 and SL1 and is compromised in the UBTF-E210K neuroregression syndrome.

Transcription of the ~200 mouse and human ribosomal RNA genes (rDNA) by RNA Polymerase I (RPI/PolR1) accounts for 80% of total cellular RNA, around 35% of all nuclear RNA synthesis, and determines the cytoplasmic ribosome complement. It is therefore a major factor controlling cell growth and its misfunction has been implicated in hypertrophic and developmental disorders. Activation of each rDNA repeat requires nucleosome replacement by the architectural multi-HMGbox factor UBTF to create a 15.

Brain Selective Estrogen Treatment Protects Dopaminergic Neurons and Preserves Behavioral Function in MPTP-induced Mouse Model of Parkinson's Disease.

Parkinson's disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra and loss of both motor and non-motor features. Several clinical and preclinical studies have provided evidence that estrogen therapy reduces the risk of PD but have limitations in terms of adverse peripheral effects. Therefore, we examined the potential beneficial effects of the brain-selective estrogen prodrug, 10β, 17β-dihydroxyestra-1,4-dien-3-one (DHED) on nigrostriatal dopaminergic neurodegeneration and behavioral abnormalities in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD.

DNA Double-Strand Break Accumulation in Alzheimer's Disease: Evidence from Experimental Models and Postmortem Human Brains.

Alzheimer's disease (AD) is a progressive neurodegenerative disease that accounts for a majority of dementia cases. AD is characterized by progressive neuronal death associated with neuropathological lesions consisting of neurofibrillary tangles and senile plaques. While the pathogenesis of AD has been widely investigated, significant gaps in our knowledge remain about the cellular and molecular mechanisms promoting AD.

DNA double-strand breaks: a potential therapeutic target for neurodegenerative diseases.

The complexity of neurodegeneration restricts the ability to understand and treat the neurological disorders affecting millions of people worldwide. Therefore, there is an unmet need to develop new and more effective therapeutic strategies to combat these devastating conditions and that will only be achieved with a better understanding of the biological mechanism associated with disease conditions. Recent studies highlight the role of DNA damage, particularly, DNA double-strand breaks (DSBs), in the progression of neuronal loss in a broad spectrum of human neurodegenerative diseases.

A recurrent de novo missense mutation in UBTF causes developmental neuroregression.

UBTF (upstream binding transcription factor) exists as two isoforms; UBTF1 regulates rRNA transcription by RNA polymerase 1, whereas UBTF2 regulates mRNA transcription by RNA polymerase 2. Herein, we describe 4 patients with very similar patterns of neuroregression due to recurrent de novo mutations in UBTF (GRCh37/hg19, NC_000017.10: g.

Role of sirtuin 1 in the regulation of hepatic gene expression by thyroid hormone.

Sirtuin 1 (SIRT1) is a nuclear deacetylase that modulates lipid metabolism and enhances mitochondrial activity. SIRT1 targets multiple transcription factors and coactivators. Thyroid hormone (T(3)) stimulates the expression of hepatic genes involved in mitochondrial fatty acid oxidation and gluconeogenesis.

Peroxisome proliferator activated receptor alpha (PPARalpha) and PPAR gamma coactivator (PGC-1alpha) induce carnitine palmitoyltransferase IA (CPT-1A) via independent gene elements.

Long chain fatty acids and pharmacologic ligands for the peroxisome proliferator activated receptor alpha (PPARalpha) activate expression of genes involved in fatty acid and glucose oxidation including carnitine palmitoyltransferase-1A (CPT-1A) and pyruvate dehydrogenase kinase 4 (PDK4). CPT-1A catalyzes the transfer of long chain fatty acids from acyl-CoA to carnitine for translocation across the mitochondrial membranes and is an initiating step in the mitochondrial oxidation of long chain fatty acids. PDK4 phosphorylates and inhibits the pyruvate dehydrogenase complex (PDC) which catalyzes the conversion of pyruvate to acetyl-CoA in the glucose oxidation pathway.

The minimal Tumor Suppressor in Lung Cancer-1 promoter is restrained by an inhibitory region.

Tumor Suppressor in Lung Cancer-1 (TSLC1) expression is repressed in many different cancers. Hypermethylation of six CpG sites upstream of the TSLC1 coding region is correlated with TSLC1 repression. However, the functional elements of the TSLC1 promoter have not been examined.

Identification of a domain within human TAF(I)48, a subunit of Selectivity Factor 1, that interacts with helix 2 of TBP.

RNA polymerase I transcription in human cells requires Selectivity Factor 1, a multisubunit complex composed of the TATA-box-binding protein (TBP) and three TBP-associated factors (TAFs) called TAF(I)48, TAF(I)63 and TAF(I)110. Each of the Selectivity Factor 1 subunits binds directly to the other three components, but these interactions have not been characterized. This study is the initial identification and analysis of a TBP-binding domain within a Selectivity Factor 1 TAF.

TFIIB-facilitated recruitment of preinitiation complexes by a TAF-independent mechanism.

Gene activators contain activation domains that are thought to recruit limiting components of the transcription machinery to a core promoter. VP16, a viral gene activator, has served as a model for studying the mechanistic aspects of transcriptional activation from yeast to human. The VP16 activation domain can be divided into two modules--an N-terminal subdomain (VPN) and a C-terminal subdomain (VPC).

The carboxyl-terminus directs TAF(I)48 to the nucleus and nucleolus and associates with multiple nuclear import receptors.

The protein complex Selectivity Factor 1, composed of TBP, TAF(I)48, TAF(I)63 and TAF(I)110, is required for rRNA transcription by RNA polymerase I in the nucleolus. The steps involved in targeting Selectivity Factor 1 will be dependent on the transport pathways that are used and the localization signals that direct this trafficking. In order to investigate these issues, we characterized human TAF(I)48, a subunit of Selectivity Factor 1.