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Title: G2E3 is a nucleo-cytoplasmic shuttling protein with DNA damage responsive localization

Abstract

G2E3 was originally described as a G2/M-specific gene with DNA damage responsive expression. The presence of a conserved HECT domain within the carboxy-terminus of the protein indicated that it likely functions as a ubiquitin ligase or E3. Although HECT domains are known to function in this capacity for many proteins, we demonstrate that a portion of the HECT domain from G2E3 plays an important role in the dynamic subcellular localization of the protein. We have shown that G2E3 is a nucleo-cytoplasmic shuttling protein with nuclear export mediated by a novel nuclear export domain that functions independently of CRM1. In full-length G2E3, a separate region of the HECT domain suppresses the function of the NES. Additionally, G2E3 contains a nucleolar localization signal (NoLS) in its amino terminus. Localization of G2E3 to the nucleolus is a dynamic process, and the protein delocalizes from the nucleolus rapidly after DNA damage. Cell cycle phase-specific expression and highly regulated subcellular localization of G2E3 suggest a possible role in cell cycle regulation and the cellular response to DNA damage.

Authors:
 [1];  [2];  [3]
  1. Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35233 (United States)
  2. Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233 (United States)
  3. Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233 (United States) and Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35233 (United States). E-mail: dfc@uab.edu
Publication Date:
OSTI Identifier:
20972116
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 313; Journal Issue: 4; Other Information: DOI: 10.1016/j.yexcr.2006.11.020; PII: S0014-4827(06)00464-2; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CELL CYCLE; DNA DAMAGES; GENE REGULATION; GENES; LIGASES

Citation Formats

Brooks, William S., Banerjee, Sami, and Crawford, David F. G2E3 is a nucleo-cytoplasmic shuttling protein with DNA damage responsive localization. United States: N. p., 2007. Web. doi:10.1016/j.yexcr.2006.11.020.
Brooks, William S., Banerjee, Sami, & Crawford, David F. G2E3 is a nucleo-cytoplasmic shuttling protein with DNA damage responsive localization. United States. doi:10.1016/j.yexcr.2006.11.020.
Brooks, William S., Banerjee, Sami, and Crawford, David F. Thu . "G2E3 is a nucleo-cytoplasmic shuttling protein with DNA damage responsive localization". United States. doi:10.1016/j.yexcr.2006.11.020.
@article{osti_20972116,
title = {G2E3 is a nucleo-cytoplasmic shuttling protein with DNA damage responsive localization},
author = {Brooks, William S. and Banerjee, Sami and Crawford, David F.},
abstractNote = {G2E3 was originally described as a G2/M-specific gene with DNA damage responsive expression. The presence of a conserved HECT domain within the carboxy-terminus of the protein indicated that it likely functions as a ubiquitin ligase or E3. Although HECT domains are known to function in this capacity for many proteins, we demonstrate that a portion of the HECT domain from G2E3 plays an important role in the dynamic subcellular localization of the protein. We have shown that G2E3 is a nucleo-cytoplasmic shuttling protein with nuclear export mediated by a novel nuclear export domain that functions independently of CRM1. In full-length G2E3, a separate region of the HECT domain suppresses the function of the NES. Additionally, G2E3 contains a nucleolar localization signal (NoLS) in its amino terminus. Localization of G2E3 to the nucleolus is a dynamic process, and the protein delocalizes from the nucleolus rapidly after DNA damage. Cell cycle phase-specific expression and highly regulated subcellular localization of G2E3 suggest a possible role in cell cycle regulation and the cellular response to DNA damage.},
doi = {10.1016/j.yexcr.2006.11.020},
journal = {Experimental Cell Research},
number = 4,
volume = 313,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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