Send to:

Choose Destination
See comment in PubMed Commons below
Mol Cell Biol. 2008 May;28(10):3313-23. doi: 10.1128/MCB.01900-07. Epub 2008 Mar 10.

A regulatory role of the Rnq1 nonprion domain for prion propagation and polyglutamine aggregates.

Author information

  • 1Department of Basic Medical Sciences, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.


Prions are infectious, self-propagating protein conformations. Rnq1 is required for the yeast Saccharomyces cerevisiae prion [PIN(+)], which is necessary for the de novo induction of a second prion, [PSI(+)]. Here we isolated a [PSI(+)]-eliminating mutant, Rnq1Delta100, that deletes the nonprion domain of Rnq1. Rnq1Delta100 inhibits not only [PSI(+)] prion propagation but also [URE3] prion and huntingtin's polyglutamine aggregate propagation in a [PIN(+)] background but not in a [pin(-)] background. Rnq1Delta100, however, does not eliminate [PIN(+)]. These findings are interpreted as showing a possible involvement of the Rnq1 prion in the maintenance of heterologous prions and polyQ aggregates. Rnq1 and Rnq1Delta100 form a sodium dodecyl sulfate-stable and Sis1 (an Hsp40 chaperone protein)-containing coaggregate in [PIN(+)] cells. Importantly, Rnq1Delta100 is highly QN-rich and prone to self-aggregate or coaggregate with Rnq1 when coexpressed in [pin(-)] cells. However, the [pin(-)] Rnq1-Rnq1Delta100 coaggregate does not represent a prion-like aggregate. These findings suggest that [PIN(+)] Rnq1-Rnq1Delta100 aggregates interact with other transmissible and nontransmissible amyloids to destabilize them and that the nonprion domain of Rnq1 plays a crucial role in self-regulation of the highly reactive QN-rich prion domain of Rnq1.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk