Publications by authors named "E Sierecki"

The compaction of chromatin is a prevalent paradigm in gene repression. Chromatin compaction is commonly thought to repress transcription by restricting chromatin accessibility. However, the spatial organization and dynamics of chromatin compacted by gene-repressing factors are unknown.

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α-Synuclein (αSyn) aggregates, detected in the biofluids of patients with Parkinson's disease (PD), have the ability to catalyze their own aggregation, leading to an increase in the number and size of aggregates. This self-templated amplification is used by newly developed assays to diagnose Parkinson's disease and turns the presence of αSyn aggregates into a biomarker of the disease. It has become evident that αSyn can form fibrils with slightly different structures, called "strains" or polymorphs, but little is known about their differential reactivity in diagnostic assays.

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The development of a flow chemistry platform for the generation of modified protein targets via expressed protein ligation (EPL) is described. The flow EPL platform enables efficient ligation reactions with high recoveries of target protein products and superior reaction rates compared to corresponding batch processes. The utility of the flow EPL technology was first demonstrated through the semisynthesis of the tick-derived chemokine-binding protein ACA-01 containing two tyrosine sulfate modifications.

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Article Synopsis
  • Chromatin compaction is a key mechanism in gene repression, traditionally believed to limit transcription by reducing chromatin accessibility.
  • Using cryo-electron tomography, researchers mapped the 3D structure of chromatin compacted by the Polycomb Repressive Complex 1 (PRC1) and CBX8, revealing that this complex is porous and stabilized by dynamic interactions.
  • The findings suggest that PRC1-chromatin condensates are not rigidly compacted, but instead remain dynamic and accessible in differentiated mouse embryonic stem cells, challenging previous assumptions about Polycomb domains.
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HIV can infect non-dividing cells because the viral capsid can overcome the selective barrier of the nuclear pore complex and deliver the genome directly into the nucleus. Remarkably, the intact HIV capsid is more than 1,000 times larger than the size limit prescribed by the diffusion barrier of the nuclear pore. This barrier in the central channel of the nuclear pore is composed of intrinsically disordered nucleoporin domains enriched in phenylalanine-glycine (FG) dipeptides.

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