The relationship of prions and translation.

Prions are infectious proteins, without the need for an accompanying nucleic acid. Nonetheless, there are connections of prions with translation and RNA, which we explore here. Most prions are based on self-propagating amyloids. The yeast [PSI+] prion is an amyloid of Sup35p, a subunit of the translation termination factor. The normal function of the Sup35p prion domain is in shortening the 3 polyA of mRNAs and thus in mRNA turnover. The [ISP+] prion is so named because it produces antisuppression, the opposite of the effect of [PSI+]. Another connection of prions with translation is the influence on prion propagation and generation of ribosome-associated chaperones, the Ssbs, and a chaperone activity intrinsic to the 60S ribosomal subunits. 2010 John Wiley & Sons, Ltd