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Updated: Nov 8, 2025

Delivery of Proteins, Peptides or Cell-impermeable Small Molecules into Live Cells by Incubation with the Endosomolytic Reagent dfTAT
Published on: September 2, 2015
A TRCky TA protein delivery service snubs the UPS
Alexander J McQuown1, Dvir Reif1, Vladimir Denic1
1Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA.
Abstract:
In mammals, tail-anchored (TA) proteins that are posttranslationally captured by the chaperone SGTA are triaged by the BAG6 complex into one of two fates: handoff to an ER targeting factor for membrane insertion or polyubiquitination for destruction by the proteasome. In this issue, Culver and Mariappan (2021. J. Cell Biol.https://doi.org/10.1083/jcb.202004086) show that a fraction of newly synthesized TA proteins is polyubiquitinated in HEK293 cells independently of the BAG6 complex yet evades proteasomal degradation by undergoing deubiquitination en route to becoming stably inserted into the ER membrane.
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