Protein translocation across the yeast microsomal membrane is stimulated by a soluble factor

Abstract

We have found that a soluble activity present in the postribosomal supernatant fraction of Saccharomyces cerevisiae stimulates posttranslational translocation of yeast prepro-α-factor across yeast microsomal membranes. Stimulation of translocation is not due to a nonspecific affect on ATP levels. The activity is likely to be due to protein(s) as it is destroyed by N-ethylmaleimide, protease, or heat treatment but not by incubation with RNase. Its apparent sedimentation coefficient is ~9.6 S. © 1986, Rockefeller University Press., All rights reserved.