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Updated: Aug 19, 2026

Applications of pHluorin for Quantitative, Kinetic and High-throughput Analysis of Endocytosis in Budding Yeast
Published on: October 23, 2016
Assembly of yeast Sec proteins involved in translocation into the endoplasmic reticulum into a membrane-bound
R J Deshaies1, S L Sanders, D A Feldheim
1Division of Biochemistry and Molecular Biology, University of California Berkeley 94720.
Abstract:
Secretory-protein translocation into the endoplasmic reticulum (ER) is thought to be catalysed by integral membrane proteins. Genetic selections uncovered three Saccharomyces cerevisiae genes (SEC61, SEC62 and SEC63), mutations in which block import of precursor proteins into the ER lumen in vivo and in vitro. The DNA sequences of SEC62 and SEC63 predict multispanning membrane proteins, and biochemical characterization of the SEC62 protein (Sec62) confirms that it is an integral ER membrane protein. Here we show that Sec61, Sec62 and Sec63 are assembled with two additional proteins into a multisubunit membrane-associated complex. These results confirm previous predictions, based upon genetic interactions between the SEC genes, that Sec61, Sec62 and Sec63 act together to facilitate protein translocation into the ER.
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