PK-sensitive PrPSc Is Infectious and Shares Basic Structural Features with PK-resistant PrPSc

PLoS Pathogens

Adriana Ramos¹  Christina J. Sigurdson¹  Miguel A. Pastrana¹  Gustavo Sajnani¹  Irina Dynin²  J. Mark Carter²  Jesús R. Requena³  Ester Vázquez-Fernández⁴  Elizabeth M. Antaki⁴  Bruce C. Onisko⁴  Melissa L. Erickson⁴  Christopher J. Silva⁴ 

[1] Department of Medicine, School of Medicine, University of Santiago de Compostela, Santiago de Compostela, Galiza, Spain;Department of Pathology, University of California, Davis, Davis, California, United States of America;Department of Pathology, University of California, San Diego, La Jolla, California, United States of America;Western Regional Research Center, United States Department of Agriculture, Albany, California, United States of America

关键词: Hamsters;    Animal prion diseases;    Sonication;    Chlorides;    Matrix-assisted laser desorption ionization time-of-flight mass spectrometry;    Proteases;    Proteolysis;    Scrapie;   

DOI  :  10.1371/journal.ppat.1002547

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

One of the main characteristics of the transmissible isoform of the prion protein (PrPSc) is its partial resistance to proteinase K (PK) digestion. Diagnosis of prion disease typically relies upon immunodetection of PK-digested PrPSc following Western blot or ELISA. More recently, researchers determined that there is a sizeable fraction of PrPSc that is sensitive to PK hydrolysis (sPrPSc). Our group has previously reported a method to isolate this fraction by centrifugation and showed that it has protein misfolding cyclic amplification (PMCA) converting activity. We compared the infectivity of the sPrPSc versus the PK-resistant (rPrPSc) fractions of PrPSc and analyzed the biochemical characteristics of these fractions under conditions of limited proteolysis. Our results show that sPrPSc and rPrPSc fractions have comparable degrees of infectivity and that although they contain different sized multimers, these multimers share similar structural properties. Furthermore, the PK-sensitive fractions of two hamster strains, 263K and Drowsy (Dy), showed strain-dependent differences in the ratios of the sPrPSc to the rPrPSc forms of PrPSc. Although the sPrPSc and rPrPSc fractions have different resistance to PK-digestion, and have previously been shown to sediment differently, and have a different distribution of multimers, they share a common structure and phenotype.

【 授权许可】

CC BY