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Title: The retinitis pigmentosa-mutated RP2 protein exhibits exonuclease activity and translocates to the nucleus in response to DNA damage

Abstract

Retinitis pigmentosa (RP) is a genetically heterogeneous disease characterized by degeneration of the retina. Mutations in the RP2 gene are linked to the second most frequent form of X-linked retinitis pigmentosa. RP2 is a plasma membrane-associated protein of unknown function. The N-terminal domain of RP2 shares amino acid sequence similarity to the tubulin-specific chaperone protein co-factor C. The C-terminus consists of a domain with similarity to nucleoside diphosphate kinases (NDKs). Human NDK1, in addition to its role in providing nucleoside triphosphates, has recently been described as a 3' to 5' exonuclease. Here, we show that RP2 is a DNA-binding protein that exhibits exonuclease activity, with a preference for single-stranded or nicked DNA substrates that occur as intermediates of base excision repair pathways. Furthermore, we show that RP2 undergoes re-localization into the nucleus upon treatment of cells with DNA damaging agents inducing oxidative stress, most notably solar simulated light and UVA radiation. The data suggest that RP2 may have previously unrecognized roles as a DNA damage response factor and 3' to 5' exonuclease.

Authors:
 [1];  [2];  [3];  [3];  [4];  [2];  [5]
  1. Division of Biology, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, CA 91010 (United States)
  2. Department of Radiation Biology, Beckman Research Institute of City of Hope, Duarte, CA 91010 (United States)
  3. Division of Immunology, Beckman Research Institute of City of Hope, Duarte, CA 91010 (United States)
  4. Division of Molecular and Cellular Neuroscience, Institute of Ophthalmology, UCL, London EC1V 9EL (United Kingdom)
  5. Division of Biology, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, CA 91010 (United States). E-mail: gpfeifer@coh.org
Publication Date:
OSTI Identifier:
20775368
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 312; Journal Issue: 8; Other Information: DOI: 10.1016/j.yexcr.2005.12.026; PII: S0014-4827(05)00621-X; Copyright (c) 2005 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; AMINO ACID SEQUENCE; CELL NUCLEI; DNA; DNA DAMAGES; EXCISION REPAIR; MUTATIONS; NUCLEOSIDES; PHOSPHOTRANSFERASES; RETINA; SUBSTRATES

Citation Formats

Yoon, Jung-Hoon, Qiu Junzhuan, Cai Sheng, Chen Yuan, Cheetham, Michael E., Shen Binghui, and Pfeifer, Gerd P. The retinitis pigmentosa-mutated RP2 protein exhibits exonuclease activity and translocates to the nucleus in response to DNA damage. United States: N. p., 2006. Web. doi:10.1016/j.yexcr.2005.12.026.
Yoon, Jung-Hoon, Qiu Junzhuan, Cai Sheng, Chen Yuan, Cheetham, Michael E., Shen Binghui, & Pfeifer, Gerd P. The retinitis pigmentosa-mutated RP2 protein exhibits exonuclease activity and translocates to the nucleus in response to DNA damage. United States. doi:10.1016/j.yexcr.2005.12.026.
Yoon, Jung-Hoon, Qiu Junzhuan, Cai Sheng, Chen Yuan, Cheetham, Michael E., Shen Binghui, and Pfeifer, Gerd P. Mon . "The retinitis pigmentosa-mutated RP2 protein exhibits exonuclease activity and translocates to the nucleus in response to DNA damage". United States. doi:10.1016/j.yexcr.2005.12.026.
@article{osti_20775368,
title = {The retinitis pigmentosa-mutated RP2 protein exhibits exonuclease activity and translocates to the nucleus in response to DNA damage},
author = {Yoon, Jung-Hoon and Qiu Junzhuan and Cai Sheng and Chen Yuan and Cheetham, Michael E. and Shen Binghui and Pfeifer, Gerd P.},
abstractNote = {Retinitis pigmentosa (RP) is a genetically heterogeneous disease characterized by degeneration of the retina. Mutations in the RP2 gene are linked to the second most frequent form of X-linked retinitis pigmentosa. RP2 is a plasma membrane-associated protein of unknown function. The N-terminal domain of RP2 shares amino acid sequence similarity to the tubulin-specific chaperone protein co-factor C. The C-terminus consists of a domain with similarity to nucleoside diphosphate kinases (NDKs). Human NDK1, in addition to its role in providing nucleoside triphosphates, has recently been described as a 3' to 5' exonuclease. Here, we show that RP2 is a DNA-binding protein that exhibits exonuclease activity, with a preference for single-stranded or nicked DNA substrates that occur as intermediates of base excision repair pathways. Furthermore, we show that RP2 undergoes re-localization into the nucleus upon treatment of cells with DNA damaging agents inducing oxidative stress, most notably solar simulated light and UVA radiation. The data suggest that RP2 may have previously unrecognized roles as a DNA damage response factor and 3' to 5' exonuclease.},
doi = {10.1016/j.yexcr.2005.12.026},
journal = {Experimental Cell Research},
number = 8,
volume = 312,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}
  • Retinitis pigmentosa (RP) is a genetically heterogeneous disease characterized by degeneration of the retina. A mutation in a new ceramide kinase (CERK) homologous gene, named CERK-like protein (CERKL), was found to cause autosomal recessive retinitis pigmentosa (RP26). Here, we show a point mutation of one of two putative nuclear localization signal (NLS) sequences inhibited the nuclear localization of the protein. Furthermore, the tetra-GFP-tagged NLS, which cannot passively enter the nucleus, was observed not only in the nucleus but also in the nucleolus. Our results provide First evidence of the active nuclear import of CERKL and suggest that the identified NLSmore » might be responsible for nucleolar retention of the protein. As recent studies have shown other RP-related proteins are localized in the nucleus or the nucleolus, our identification of NLS in CERKL suggests that CERKL likely plays important roles for retinal functions in the nucleus and the nucleolus.« less
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  • The planar cell polarity (PCP) pathway, a {beta}-catenin-independent branch of the Wnt signaling pathway, orients cells and their appendages with respect to the body axes. Diversin, the mammalian homolog of the Drosophila PCP protein Diego, acts as a molecular switch that blocks {beta}-catenin-dependent and promotes {beta}-catenin-independent Wnt signaling. We report now that Diversin, containing several nuclear localization signals, translocates to the nucleus, where it interacts with the transcription factor AF9. Both Diversin and AF9 block canonical Wnt signaling; however, this occurs independently of each other, and does not require nuclear Diversin. In contrast, AF9 strongly augments the Diversin-driven activation ofmore » c-Jun N-terminal kinase (JNK)-dependent gene expression in the nucleus, and this augmentation largely depends on the presence of nuclear Diversin. Thus, our findings reveal that components of the PCP cascade translocate to the nucleus to participate in transcriptional regulation and PCP signaling.« less
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