RESUMO
BACKGROUND: Regulation of gene transcription in response to stress is central to a cell's ability to cope with environmental challenges. Taf14 is a YEATS domain protein in S.cerevisiae that physically associates with several transcriptionally relevant multisubunit complexes including the general transcription factors TFIID and TFIIF and the chromatin-modifying complexes SWI/SNF, INO80, RSC and NuA3. TAF14 deletion strains are sensitive to a variety of stresses suggesting that it plays a role in the transcriptional stress response. RESULTS: In this report we survey published genome-wide transcriptome and occupancy data to define regulatory properties associated with Taf14-dependent genes. Our transcriptome analysis reveals that stress related, TATA-containing and SAGA-dependent genes were much more affected by TAF14 deletion than were TFIID-dependent genes. Comparison of Taf14 and multiple transcription factor occupancy at promoters genome-wide identified a group of proteins whose occupancy correlates with that of Taf14 and whose proximity to Taf14 suggests functional interactions. We show that Taf14-repressed genes tend to be extensively regulated, positively by SAGA complex and the stress dependent activators, Msn2/4 and negatively by a wide number of repressors that act upon promoter chromatin and TBP. CONCLUSIONS: Taken together our analyses suggest a novel role for Taf14 in repression and derepression of stress induced genes, most probably as part of a regulatory network which includes Cyc8-Tup1, Srb10 and histone modifying enzymes.
Assuntos
Regulação Fúngica da Expressão Gênica , Proteínas de Saccharomyces cerevisiae/metabolismo , Fator de Transcrição TFIID/metabolismo , Perfilação da Expressão Gênica , Genômica , Resposta ao Choque Térmico/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologiaRESUMO
Identification of multiple histone acylations diversifies transcriptional control by metabolism, but their functions are incompletely defined. Here we report evidence of histone crotonylation in the human fungal pathogen Candida albicans. We define the enzymes that regulate crotonylation and show its dynamic control by environmental signals: carbon sources, the short-chain fatty acids butyrate and crotonate, and cell wall stress. Crotonate regulates stress-responsive transcription and rescues C. albicans from cell wall stress, indicating broad impact on cell biology. The YEATS domain crotonylation readers Taf14 and Yaf9 are required for C. albicans virulence, and Taf14 controls gene expression, stress resistance, and invasive growth via its chromatin reader function. Blocking the Taf14 C terminus with a tag reduced virulence, suggesting that inhibiting Taf14 interactions with chromatin regulators impairs function. Our findings shed light on the regulation of histone crotonylation and the functions of the YEATS proteins in eukaryotic pathogen biology and fungal infections.
Assuntos
Candida albicans/metabolismo , Proteínas Fúngicas/metabolismo , Histonas/metabolismo , Animais , Candida albicans/patogenicidade , Cromatina/metabolismo , Crotonatos/metabolismo , Feminino , Histona Acetiltransferases/metabolismo , Humanos , Camundongos , Domínios Proteicos , Fator de Transcrição TFIID , VirulênciaRESUMO
Background Although environmental factors induce development of type 1 diabetes mellitus (T1DM) in genetically susceptible individuals, many of those factors have been uncovered. Therefore, the aim of the present study was to analyze associations of T1DM with a wide range of environmental factors. Material and Methods A case-control study was conducted on 249 diabetic and 255 healthy individuals from the Dalmatian region of South Croatia. Data regarding risk factors during pregnancy and early life period of the child were evaluated. Results History of antihypertensive intake (p=0.04) and frequency of stressful life events during pregnancy (p=0.01) were associated with higher risk of T1DM, while hypertension was associated with lower risk of T1DM (p=0.01). Maternal age<25 years at delivery was associated with a higher risk of T1DM (p=0.01).Diabetic patients had a positive family history of T1DM or T2DM (p=0.002) more frequently than controls, while history of infectious diseases was inversely associated with the risk of T1DM (p=0.03). A higher risk of T1DM was significantly associated with earlier introduction of cow's milk (p=0.001), higher number of meals consumed per day (p=0.02), higher frequency of carbohydrate (p=0.001) and meat (p=0.01) consumption and stressful life events during childhood (p=0.02) while earlier introduction of fruit was associated with a lower risk of T1DM (p=0.03) Conclusion This case-control study confirmed associations of a large number of environmental factors with development of T1DM with emphasis on the association of mother's antihypertensive intake during pregnancy, which extends our knowledge about environmental factors related with development of T1DM.
Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Estudos de Casos e Controles , Criança , Pré-Escolar , Croácia/epidemiologia , Diabetes Mellitus Tipo 1/etiologia , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/efeitos adversos , Feminino , Humanos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Fatores de RiscoRESUMO
Hashimoto's thyroiditis (HT) is the most common form of autoimmune thyroid diseases (AITD) characterized by progressive destruction of thyroid tissue that may lead to hypothyroidism. High thyroid autoantibodies against thyroid peroxidase (TPOAb) levels are present in 90% of patients with HT and serve as a clinical marker for the detection of early AITD/HT. The main aim of our study was to test whether recently identified genetic variants associated with TPOAb are also involved in HT development. A total of 504 unrelated individuals, including 200 patients with HT and 304 controls, were involved in this study. Diagnosis of HT cases was based on clinical examination, measurement of thyroid hormones (TSH and fT4) and antibodies (TgAb, TPOAb) and ultrasound examination. We selected and genotyped 14 known TPOAb-associated genetic variants. Case-control logistic regression model was used to test the association of selected genetic variants with HT. Additionally, we tested association of the same genetic variants with thyroid related quantitative traits (TPOAb levels, TgAb levels and thyroid gland volume) using linear regression. Three genetic variants showed nominal association with HT; rs10774625 in ATXN2 gene (p = 0.0149, OR = 0.73, CI = 0.56-0.94), rs7171171 near RASGRP1 gene (p = 0.0356, OR = 1.4, CI = 1.02-1.92) and rs11675434 in TPO gene (p = 0.041, OR = 1.31, CI = 1.01-1.69). Two of these SNPs (rs1077462, rs11675434) also showed association with TPOAb levels (p = 0.043, ß = -0.39; p = 0.042, ß = 0.40, respectively) and one (rs7171171) was associated with thyroid gland volume (p = 0.0226, ß = -0.21). Our findings suggest that variants inside or near TPO, ATXN2 and RASGRP1 genes are associated with HT. Identified loci are novel to HT and represent good basis for further exploration of HT susceptibility.