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Updated: Apr 15, 2026

In Vesiculo Synthesis of Peptide Membrane Precursors for Autonomous Vesicle Growth
Published on: June 28, 2019
Synthesis of a peptide that can translocate to the endoplasmic reticulum
Kanako Nakatsu1, Toru Hosoi1, Keisuke Toyoda1
1Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
Abstract:
The accumulation of unfolded proteins in the endoplasmic reticulum (ER) leads to ER stress, which has been implicated in the development of diseases. In the present study, we synthesized a peptide that entered cells and translocated to the ER. This peptide possessed fluorescein isothiocyanate (FITC), HIV-TAT, mini-αA-crystallin, and KDEL sequences. We demonstrated that this peptide entered cells and translocated to the ER. Time course experiments revealed that this peptide existed in the ER of cos-7 cells for 16 h. Furthermore, we detected the full-length peptide in cells by fluorescent immunostaining followed by SDS-PAGE. The peptide also entered glial and neuronal cells. These results suggest that this peptide has the ability to enter cells and exert chaperone activity at the ER, and provide an insight into the development of new drugs.
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