Misfolded opsin mutants display elevated beta-sheet structure

作者：Miller Lisa M^*; Gragg Megan; Kim Tae Gyun; Park Paul S H

来源：FEBS LETTERS, 2015, 589(20): 3119-3125.

DOI：10.1016/j.febslet.2015.08.042

• G protein-coupled receptor
• Membrane protein
• Protein aggregation
• Protein misfolding
• Secondary structure
• Retinal degeneration

Mutations in rhodopsin can cause misfolding and aggregation of the receptor, which leads to retinitis pigmentosa, a progressive retinal degenerative disease. The structure adopted by misfolded opsin mutants and the associated cell toxicity is poorly understood. Forster resonance energy transfer (FRET) and Fourier transform infrared (FTIR) microspectroscopy were utilized to probe within cells the structures formed by G188R and P23H opsins, which are misfolding mutants that cause autosomal dominant retinitis pigmentosa. Both mutants formed aggregates in the endoplasmic reticulum and exhibited altered secondary structure with elevated p-sheet and reduced a-helical content. The newly formed p-sheet structure may facilitate the aggregation of misfolded opsin mutants. The effects observed for the mutants were unrelated to retention of opsin molecules in the endoplasmic reticulum itself.

• 出版日期2015-10-7