Mutation in ADORA1 identified as likely cause of early-onset parkinsonism and cognitive dysfunction.

BACKGROUND: We aimed to identify the genetic cause of neurological disease in an Iranian family whose manifestations include symptoms of parkinsonism and cognitive dysfunction. METHODS: Clinical data on the patients were gathered by interviews with parents, neurological examinations, and laboratory tests. Genetic analysis was performed by genome-wide single-nucleotide polymorphism homozygosity mapping and exome sequencing. The effect of putative disease-causing mutation was assessed by immunocytochemistry on HEK293 cells and Western blotting on proteins extracted from HEK293 cells transfected with wild-type and mutated genes. RESULTS: Homozygosity mapping and exome sequencing led to identification of a mutation in ADORA1 that causes p.Gly279Ser in the encoded protein, adenosine A1 receptor (A1 R), as the probable cause of disease. The mutation segregated with disease status in the family, affects a highly conserved amino acid, and was absent in 700 controls. CONCLUSIONS: The known biological activities of A1 R in brain functions including its physical interaction with and inhibitory effect on dopamine receptor D1 provide supportive evidence that disruptions of A1 R may result in neurological dysfunction. Also, recent evidence on the related adenosine A2B receptor marks the domain in which the mutation is positioned as important for function. Finally, ADORA1 is located within the Parkinson's disease locus PARK16, which has been identified in several populations. ADORA1 may be the PD susceptibility gene within this locus. The molecular mechanism by which p.Gly279Ser disrupts A1 R function remains unknown, but a quantitative effect on interaction with the dopamine receptor was not shown. © 2016 International Parkinson and Movement Disorder Society.

Selenite and methylseleninic acid epigenetically affects distinct gene sets in myeloid leukemia: A genome wide epigenetic analysis.

Selenium compounds have emerged as promising chemotherapeutic agents with proposed epigenetic effects, however the mechanisms and downstream effects are yet to be studied. Here we assessed the effects of the inorganic selenium compound selenite and the organic form methylseleninic acid (MSA) in a leukemic cell line K562, on active (histone H3 lysine 9 acetylation, H3K9ac and histone H3 lysine 4 tri-methylation, H3K4me3) and repressive (histone H3 lysine 9 tri-methylation, H3K9me3) histone marks by Chromatin immunoprecipitation followed by DNA sequencing (ChIP-Seq). Both selenite and MSA had major effects on histone marks but the effects of MSA were more pronounced. Gene ontology analysis revealed that selenite affected genes involved in response to oxygen and hypoxia, whereas MSA affected distinct gene sets associated with cell adhesion and glucocorticoid receptors, also apparent by global gene expression analysis using RNA sequencing. The correlation to adhesion was functionally confirmed by a significantly weakened ability of MSA treated cells to attach to fibronectin and linked to decreased expression of integrin beta 1. A striking loss of cellular adhesion was also confirmed in primary patient AML cells. Recent strategies to enhance the cytotoxicity of chemotherapeutic drugs by disrupting the interaction between leukemic and stromal cells in the bone marrow are of increasing interest; and organic selenium compounds like MSA might be promising candidates. In conclusion, these results provide new insight on the mechanism of action of selenium compounds, and will be of value for the understanding, usage, and development of new selenium compounds as anticancer agents.

Study of a polymerase chain reaction-based method for detection of herpes simplex virus type 1 DNA among Iranian patients with ocular herpetic keratitis infection.

PURPOSE: To study the presence of the herpes simplex virus type 1 (HSV-1) glycoprotein D gene in tear films of Iranian patients with herpetic keratitis. METHODS: Twenty-five tear film and eye swab specimens from 25 herpetic keratitis patients and 10 specimens from 10 healthy volunteers were collected in the Farabi Eye Hospital, Tehran, Iran. HSV-1 DNA was detected by using the nested polymerase chain reaction (nPCR) method. Viral isolation was done using conventional viral techniques. A monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) was used for confirmation of positive cytopathic effect cell culture. The results of a diagnosis by an ophthalmologist team were compared with those of nPCR. RESULTS: HSV-1 DNA was identified in tear films of 88% (23/25) of suspected herpetic keratitis patients. All healthy controls (100%) had negative PCR results. HSV-1 was isolated in cell culture and confirmed by ELISA in 12% (3/25) of herpetic keratitis patients who had epithelial keratitis. The kappa value showed a high level of agreement between ophthalmologist team diagnosis and the PCR results (kappa = 0.86, P < 0.0001). CONCLUSIONS: nPCR is a sensitive, rapid, and powerful tool for detection of HSV-1 DNA in tear films of ocular herpetic keratitis patients and can serve as a supplemental method for diagnosis of herpetic keratitis infection.

Genomic DNA hypomethylation by histone deacetylase inhibition implicates DNMT1 nuclear dynamics.

Histone deacetylase inhibitors (HDACi) are promising antitumor drugs acting through reactivation of silenced tumor suppressor genes. Several HDACi are currently in clinical trials both for hematological and solid tissue malignancies. Cooperative action of HDACi and DNA methylation inhibitors (DNMTi) has been reported, making combined treatment an attractive choice for cancer therapy. There is some evidence that synergistic effects of HDACi and DNMTi are achieved by their action on common targets, including DNA methyltransferase 1 (DNMT1). To further analyze this interaction, we investigated the effect of the HDACi trichostatin A on global and gene-specific DNA methylation and applied methods with single molecule sensitivity, confocal laser scanning microscopy with avalanche photodiode detectors (APD imaging) and fluorescence correlation spectroscopy (FCS), to study its effect on the nuclear dynamics of DNMT1 in live cells. Our data show that trichostatin A treatment reduces global DNA methylation and the DNMT1 protein level and alters DNMT1 nuclear dynamics and interactions with chromatin. The mechanisms underlying these effects are apparently distinct from the mechanisms of action of the DNMT inhibitor 5-azacytidine. Our study sheds light on the molecular mechanisms underlying the synergistic action of HDACi and DNMTi and may also help to define improved policies for cancer treatment.