Epidermal Growth Factor Stimulates Extracellular-Signal Regulated Kinase Phosphorylation of a Novel Site on Cytoplasmic Dynein Intermediate Chain 2

ArticleinInternational Journal of Molecular Sciences 14(2):3595-620 · February 2013with26 Reads
DOI: 10.3390/ijms14023595 · Source: PubMed
Extracellular-signal regulated kinase (ERK) signaling is required for a multitude of physiological and patho-physiological processes. However, the identities of the proteins that ERK phosphorylates to elicit these responses are incompletely known. Using an affinity purification methodology of general utility, here we identify cytoplasmic dynein intermediate chain 2 (DYNC1I-2, IC-2) as a novel substrate for ERK following epidermal growth factor receptor stimulation of fibroblasts. IC-2 is a subunit of cytoplasmic dynein, a minus-end directed motor protein necessary for transport of diverse cargos along microtubules. Emerging data support the hypothesis that post-translational modification regulates dynein but the signaling mechanisms used are currently unknown. We find that ERK phosphorylates IC-2 on a novel, highly conserved Serine residue proximal to the binding site for the p150Glued subunit of the cargo adapter dynactin. Surprisingly, neither constitutive phosphorylation nor a phosphomimetic substitution of this Serine influences binding of p150Glued to IC-2. These data suggest that ERK phosphorylation of IC-2 regulates dynein function through mechanisms other than its interaction with dynactin.
    • "Combining a series of antibodies designed to enrich Ser/Thr kinases, Akt/P13K, and Tyr kinases, core proteins that are involved in many different regulator pathways such as Akt signaling, MAP kinase signaling, cell cycle regulation, etc. were successfully detected [19]. Many of the commercial kits have been designed for human or mouse cell lines and have shown good efficiency and specificity [25, 26]. To the best of our knowledge, there are no kits with specific antibodies for phosphoproteins in plant pathways. "
    [Show abstract] [Hide abstract] ABSTRACT: Plants are sessile organisms that need to respond to environmental changes quickly and efficiently. They can accomplish this by triggering specialized signaling pathways often mediated by protein phosphorylation and dephosphorylation. Phosphorylation is a fast response that can switch on or off a myriad of biological pathways and processes. Proteomics and mass spectrometry (MS) are the main tools employed in the study of protein phosphorylation. Advances in the technologies allow simultaneous identification and quantification of thousands of phosphopeptides and proteins that are essential to understanding the sophisticated biological systems and regulations. In this review we summarize the advances in phosphopeptide enrichment and quantitation, MS for phosphorylation site mapping and new data acquisition methods, databases and informatics, interpretation of biological insights and crosstalk with other PTMs, as well as future directions and challenges in the field of phosphoproteomics. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Article · Mar 2015
    • "Therefore, the regulation of growth factor receptor signaling is essential for the understanding of physiology and pathophysiology of these proteins. In this regard, the link of EGFR to the intracellular dynein IC2 was described by Pullikuth et al. [13]. Furthermore, mechanisms for the spatial regulation of EGFR signaling including endocytosis were elucidated by Ceresa et al. [14]. "
    [Show abstract] [Hide abstract] ABSTRACT: In the special issue "Signaling Molecules and Signal Transduction in Cells" authors were invited to submit papers regarding important and novel aspects of extra- and intracellular signaling which have implications on physiological and pathophysiological processes. These aspects included compounds which are involved in these processes, elucidation of signaling pathways, as well as novel techniques for the analysis of signaling pathways. In response, various novel and important topics are elucidated in this special issue.
    Full-text · Article · Jun 2013
  • [Show abstract] [Hide abstract] ABSTRACT: The motor protein, cytoplasmic dynein is responsible for the movement of a variety of cargoes toward microtubule minus ends in cells. Little is understood about how dynein is regulated to specifically transport its various cargoes. In vertebrates, the dynein motor domain (DYNC1H) is encoded by a single gene; while there are two genes for the five smaller subunits that comprise the cargo binding domain of the dynein complex. The isoforms of the intermediate chain (DYNC1I) provide a good model system with which to study the roles the different isoforms of the cargo domain subunits have in designating specific dynein functions. The intermediate chains (DYNC1I) play a key scaffold role in the dynein complex. In neurons, dynein complexes with different intermediate chain isoforms have distinct roles, including cargo binding and transport. Some of the phospho-isoforms of the intermediate chain also specify binding to specific cargo. These data support the model that cytoplasmic dynein can be specifically regulated through the different isoforms of the subunits.
    Article · Jan 2015
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