Aurora-A phosphorylates, activates, and relocalizes the small GTPase RalA.

Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA.
Molecular and Cellular Biology (Impact Factor: 5.04). 11/2009; 30(2):508-23. DOI: 10.1128/MCB.00916-08
Source: PubMed

ABSTRACT The small GTPase Ras, which transmits extracellular signals to the cell, and the kinase Aurora-A, which promotes proper mitosis, can both be inappropriately activated in human tumors. Here, we show that Aurora-A in conjunction with oncogenic Ras enhances transformed cell growth. Furthermore, such transformation and in some cases also tumorigenesis depend upon S194 of RalA, a known Aurora-A phosphorylation site. Aurora-A promotes not only RalA activation but also translocation from the plasma membrane and activation of the effector protein RalBP1. Taken together, these data suggest that Aurora-A may converge upon oncogenic Ras signaling through RalA.

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