Work

Site-Specific Structure and Dynamics of Polyglutamine-Containing Amyloid Fibrils and the Caveolin Scaffolding Domain by Magic Angle Spinning Solid-State NMR

Year: 2014

Type: article

Abstract: Protein assemblies and membrane associations play important roles in health and disease. Structural studies of these biological complexes are thus vital, but are often unfeasible by conventional tools in structural biology. Solid-state NMR (ssNMR) has made possible atomic-level structural studies of large, insoluble, and non-crystalline biological systems, such as amyloid fibrils and membrane proteins. Amyloid fibrils are associated with at least 20 human diseases, making structural aspects of their formation crucial to understanding their aggregation pathways. Huntington’s disease (HD) is caused by an expansion beyond a threshold of the polyglutamine (polyQ) domain in the Exon 1 of the huntingtin protein (htt). The 17-residue N-terminal segment of the Exon 1 (httNT) initiates the fibril aggregation and helps stabilize oligomers and fibrils. On the contrary, a polyPro segment C-terminal to the polyQ reduces fibril aggregation. In this thesis, magic-angle spinning (MAS) ssNMR was used to elucidate atomic-resolution structure and dynamics of the polyQ and its flanking domains in polyQ-containing amyloid-like fibrils. More than 25% of human proteins are membrane proteins. Caveolin-1 (Cav1) is a protein found associated with cholesterol-rich membranes that forms caveolae, curved cave-like invaginations in the plasma membrane, and is implicated in muscular diseases and cancers. The caveolin-scaffolding domain (CSD) of Cav1 is responsible for cholesterol-recognition and oligomerization to form the caveolae. In this thesis, MAS and static ssNMR are used to elucidate molecular structure of the CSD and its perturbation of the lipid bilayer in a cholesterol-rich lipid environment. These results allow for a more thorough understanding of the role of CSD in caveolae formation.

Source: D-Scholarship@Pitt (University of Pittsburgh)

Author: Cody L. Hoop

Language: English

Topic: Advanced NMR Techniques and Applications

Subfield: Spectroscopy

Field: Chemistry

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: green

Funders: University of Pittsburgh, National Institutes of Health, National Institute on Aging, National Institute of General Medical Sciences

Awards: Mechanisms of amyloid nucleation, Structures and Properties of Polyglutamine Proteins and Their Aggregates

OpenAlex ID: W114646072