Publications by authors named "Heidi Standke"
NifA is a σ activator that turns on bacterial nitrogen fixation under reducing conditions and when fixed cellular nitrogen levels are low. The redox sensing mechanism in NifA is poorly understood. In α- and β-proteobacteria, redox sensing involves two pairs of Cys residues within and immediately following the protein's central AAA domain.
View Article and Find Full Text PDFSelect prion diseases are characterized by widespread cerebral plaque-like deposits of amyloid fibrils enriched in heparan sulfate (HS), a abundant extracellular matrix component. HS facilitates fibril formation in vitro, yet how HS impacts fibrillar plaque growth within the brain is unclear. Here we found that prion-bound HS chains are highly sulfated, and that the sulfation is essential for accelerating prion conversion in vitro.
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- Tau neurofibrillary tangles are a key indicator of Alzheimer's disease, and while their association with certain types of tau seeds is unclear, research shows that specific tau seeds (3R/4R) can be quantified using RT-QuIC assays in brain tissue.
- These assays reveal that tau seeding activity can be detected before any visible tau deposits appear, indicating a possible early biomarker for Alzheimer's progression, especially in late disease stages.
- The study also found that 3R/4R tau seeds are not only prevalent in Alzheimer's patients but also present in other neurodegenerative conditions like Lewy body disease, with notable gender differences in tau levels, particularly in more advanced disease stages.
Article Synopsis
- The study presents a high-resolution structure of the RML scrapie prion strain, revealing a core composed of parallel β-sheets similar to the hamster 263K strain.
- Structural similarities include specific motifs like a steric zipper and β-arches, but notable differences exist in their topology.
- Despite lacking certain anchors and glycans, the core conformation of the RML prion is similar to wildtype RML prions, highlighting both commonalities and differences among prion strains.
The accumulation of misfolded proteins as amyloid fibrils in the brain is characteristic of most neurodegenerative disorders. These misfolded proteins are capable of self-amplifying through protein seeding mechanisms, leading to accumulation in the host. First shown for PrP prions and prion diseases, it is now recognized that self-propagating misfolded proteins occur broadly in neurodegenerative diseases and include amyloid-β (Aβ) and tau in Alzheimer's disease (AD), tau in chronic traumatic encephalopathy (CTE), Pick's disease (PiD), corticobasal degeneration (CBD), and progressive supranuclear palsy (PSP), and α-synuclein (α-syn) in Parkinson's disease (PD) and Lewy body dementias (LBD).
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