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Updated: Oct 14, 2026

Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells
Published on: December 17, 2012
GTP-dependent ADP-ribosylation of a 22 kDa protein in the endoplasmic reticulum membrane
Abstract:
Treatment of salt-stripped rough microsomal membranes from pancreas or liver with NAD and cholera toxin in the presence of GTP yields an ADP-ribosylated non-ribosomal 22 kDa protein. Membranes containing the modified protein are less active in the co-translational processing of secretory preproteins translated from isolated mRNA in a reticulocyte translation system, but signal peptidase activity is unchanged, suggesting that the 22 kDa protein is involved in the targetting or translocation of secretory proteins at the membrane of the endoplasmic reticulum.
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