کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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4570599 | 1332053 | 2013 | 12 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A Crucial Role of the RGS Domain in Trans-Golgi Network Export of AtRGS1 in the Protein Secretory Pathway A Crucial Role of the RGS Domain in Trans-Golgi Network Export of AtRGS1 in the Protein Secretory Pathway](/preview/png/4570599.png)
ABSTRACTThe secretory pathway is responsible for the transport of newly synthesized transmembrane proteins from the endoplasmic reticulum to their destinations via the Golgi/trans-Golgi network (TGN). Cargo proteins at each station are actively sorted by specific sorting signals on the cargo and the corresponding coat complexes. Here, we used the Arabidopsis regulator of G-protein signaling (AtRGS1), which contains an N-terminal potentially sensing glucose seven-transmembrane domain and a C-terminal RGS domain, as a model to uncover sorting motifs required for its cell surface expression. Expression of wild-type and truncated or mutated AtRGS1 fluorescent fusion proteins identified two cysteine residues in the extracellular N-terminus that are essential for endoplasmic reticulum exit and/or correct folding of AtRGS1. The linker between the seven-transmembrane and RGS domains contains an endoplasmic reticulum export signal, whereas the C-terminus is dispensable for the plasma membrane expression of AtRGS1. Interestingly, deletion of the RGS domain results in Golgi/TGN localization of the truncated AtRGS1. Further analysis using site-directed mutagenesis showed that a tyrosine-based motif embedded in the RGS domain is essential for Golgi/TGN export of AtRGS1. These results reveal a new role for the RGS domain in regulating AtRGS1 trafficking from the Golgi/TGN to the plasma membrane and explain the interaction between the seven-transmembrane and RGS domains.SUMMARYAtRGS1 is a unique protein in the system of G-protein signaling, which contains two functionally opposite domains: 7TM and RGS. Our data revealed a novel role of the RGS domain in regulating AtRGS1 trafficking from the trans-Golgi network (TGN) to plasma membrane.
Journal: - Volume 6, Issue 6, November 2013, Pages 1933–1944