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Updated: Feb 14, 2026

Measuring Peptide Translocation into Large Unilamellar Vesicles
Published on: January 27, 2012
Positive zip coding in small protein translocation
Yukari Okamoto1, Sojin Shikano2
1From the Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois 60607-7170.
Abstract:
Most newly synthesized proteins destined for the secretory pathway contain a signal peptide (SP) that triggers cotranslational translocation into the endoplasmic reticulum (ER). However, how small polypeptides undergo ER translocation is not fully understood. In this issue of JBC, Guo et al. describe a mechanism for posttranslational translocation of small secretory proteins featuring a positive charge within the SP N-terminal region. Defects in this element disrupt proper secretion and explain the effects of genetic mutations associated with one type of diabetes.
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