Graves’ Ophthalmopathy: A Comprehensive Role For Platelet-Derived Growth Factors

Autoimmune thyroid disorders include Graves’ disease (GD), which leads to hyperthyroidism, and Hashimoto’s thyroiditis, which leads to hypothyroidism. The incidence of autoimmune hypothyroidism is around five times higher than the incidence of autoimmune hyperthyroidism, but together these autoimmune thyroid disorders are the most common autoimmune conditions in the Western population and affect around 2-5% of the population. Estimates for the incidence of autoimmune hyperthyroidism vary considerably, but a recent review estimates an incidence of 80/100.000/year for women and 8/100.000/year for men in Caucasian populations. Graves’ disease (GD) is the most common cause of hyperthyroidism in Western and other iodine-sufficient populations, and accounts for ~80% of cases of hyperthyroidism

High-throughput assessment of context-dependent effects of chromatin proteins

Background: Chromatin proteins control gene activity in a concerted manner. We developed a high-throughput assay to study the effects of the local chromatin environment on the regulatory activity of a protein of interest. The assay combines a previously reported multiplexing strategy based on barcoded randomly integrated reporters with Gal4-mediated tethering. We applied the assay to Drosophila heterochromatin protein 1a (HP1a), which is mo

Social anxiety and perceptions of likeability by peers in children

The current study aimed to investigate the discrepancy between self-reported and peer-reported likeability among children, and the relation with social anxiety, depression, and social support. In total, 532 children between 7 and 12 years completed questionnaires about social anxiety symptoms, depressive symptoms, and social support, estimated their own likeability, and indicated how much they liked their classmates. Children with higher levels of social anxiety or depression overestimated their likeability less or even underestimated their likeability. Social anxiety symptoms, but not depressive symptoms, were significant predictors of the discrepancy. Social support was positively related to likeability and negatively related to social anxiety, but did not moderate the association between social anxiety symptoms and perception accuracy of likeability. These results are in line with cognitive theories of childhood social anxiety, and they stress the importance of using multi-informant measures when studying the relation between social anxiety and social functioning in children

Local rewiring of genome-nuclear lamina interactions by transcription

Transcriptionally inactive genes are often positioned at the nuclear lamina (NL), as part of large lamina-associated domains (LADs). Activation of such genes is often accompanied by repositioning toward the nuclear interior. How this process works and how it impacts flanking chromosomal regions are poorly understood. We addressed these questions by systematic activation or inactivation of individual genes, followed by detailed genome-wide analysis of NL interactions, replication timing, and transcription patterns. Gene activation inside LADs typically causes NL detachment of the entire transcription unit, but rarely more than 50-100 kb of flanking DNA, even when multiple neighboring genes are activated. The degree of detachment depends on the expression level and the length of the activated gene. Loss of NL interactions coincides with a switch from late to early replication timing, but the latter can involve longer stretches of DNA. Inactivation of active genes can lead to increased NL contacts. These extensive datasets are a resource for the analysis of LAD rewiring by transcription and reveal a remarkable flexibility of interphase chromosomes

Widespread chromatin context-dependencies of DNA double-strand break repair proteins

DNA double-strand breaks are repaired by multiple pathways, including non-homologous end-joining (NHEJ) and microhomology-mediated end-joining (MMEJ). The balance of these pathways is dependent on the local chromatin context, but the underlying mechanisms are poorly understood. By combining knockout screening with a dual MMEJ:NHEJ reporter inserted in 19 different chromatin environments, we identified dozens of DNA repair proteins that modulate pathway balance dependent on the local chromatin state. Proteins that favor NHEJ mostly synergize with euchromatin, while proteins that favor MMEJ generally synergize with distinct types of heterochromatin. Examples of the former are BRCA2 and POLL, and of the latter the FANC complex and ATM. Moreover, in a diversity of human cancer types, loss of several of these proteins alters the distribution of pathway-specific mutations between heterochromatin and euchromatin. Together, these results uncover a complex network of proteins that regulate MMEJ:NHEJ balance in a chromatin context-dependent manner.</p

Widespread chromatin context-dependencies of DNA double-strand break repair proteins

DNA double-strand breaks are repaired by multiple pathways, including non-homologous end-joining (NHEJ) and microhomology-mediated end-joining (MMEJ). The balance of these pathways is dependent on the local chromatin context, but the underlying mechanisms are poorly understood. By combining knockout screening with a dual MMEJ:NHEJ reporter inserted in 19 different chromatin environments, we identified dozens of DNA repair proteins that modulate pathway balance dependent on the local chromatin state. Proteins that favor NHEJ mostly synergize with euchromatin, while proteins that favor MMEJ generally synergize with distinct types of heterochromatin. Examples of the former are BRCA2 and POLL, and of the latter the FANC complex and ATM. Moreover, in a diversity of human cancer types, loss of several of these proteins alters the distribution of pathway-specific mutations between heterochromatin and euchromatin. Together, these results uncover a complex network of proteins that regulate MMEJ:NHEJ balance in a chromatin context-dependent manner.</p