Signal trafficking

GPI-anchored proteins constitute a quite diverse family of cell-surface molecules that participate in such processes as nutrient uptake, cell adhesion, and membrane signaling events [3]. All GPI-linked proteins are destined for the cell surface via trafficking through the secretory pathway, where they acquire the... 

Researchers found that NAD serves as a substrate in poly(ADP-ribose) synthesis, a reaction important for DNA repair processes. In addition, it takes part in mono (ADP-ribosyl)ation reactions that are involved in endogenous regulation of many aspects of signal transduction and membrane trafficking in eukaryotic cells. 

Since the SUMO pathway affects multiple pathways ranging from transcription, DNA repair, and intracellular trafficking over cell signaling and cell cycle control to basic metabolism, it is not suiprising that links to diseases and viral assaults are emerging. However, the field is not yet at a stage sufficiently developed for pharmacological intervention. Below we will describe selected examples for links of the SUMO pathway to diseases and viral functions. 

Reiter E, Lefkowitz RJ (2006) GRKs and beta-arrestins roles in receptor silencing, trafficking and signaling. Trends Endocrinol Metab 17 159-165... 

On the molecular level, all TAARs for which ligands are available, couple to Gas, at least in recombinant systems. Links to other signaling pathways as well as potential heterodimerization within the TAAR family or with other GPCRs have so far not been observed. All TAAR genes have a very similar size of about 1 kb, and posttranslational modification and subcellular trafficking of the receptors are both not well understood. 

In addition to the membrane-inserted core domain of Kv channels, their cytoplasmic domains have important roles for Kv-channel function [5]. Many of these functions are related to subunits assembly, channel trafficking to and from the plasma membrane, and interactions with cytoskeletal components (Fig. la). A tetramerization (T) domain for subunit assembly has been well defined in Shaker-channels, where it is localized in the amino-terminus. Other Kv-channels (e.g., eag, HERG, KvLQTl) may have comparable domains within the cytoplasmic carboxy-terminus. ER retention and retrieval signals have been found... 

Blanpain C, Wittamer V, Vanderwinden JM, et al. Palmitoylation of CCR5 is critical for receptor trafficking and efficient activation of intracellular signaling pathways. J Biol Chem 2001 276(26) 23795-23804. 

Kim CH, Broxmeyer HE. Chemokines signal lamps for trafficking of T and B cells for development and effector function. J Leukoc Biol 1999 65 6-15. 

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