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Title: Zcchc8 is a glycogen synthase kinase-3 substrate that interacts with RNA-binding proteins

Abstract

Phosphorylation of c-Myc on threonine 58 (T58) stimulates its degradation by the Fbw7-SCF ubiquitin ligase. We used a phosphorylation-specific antibody raised against the c-Myc T58 region to attempt to identify other proteins regulated by the Fbw7 pathway. We identified two predominant proteins recognized by this antibody. The first is Ebna1 binding protein 2, a nucleolar protein that, in contrast with a previous report, is likely responsible for the nucleolar staining exhibited by this antibody. The second is Zcchc8, a nuclear protein that is highly phosphorylated in cells treated with nocodazole. We show that Zcchc8 is directly phosphorylated by GSK-3 in vitro and that GSK-3 inhibition prevents Zcchc8 phosphorylation in vivo. Moreover, we found that Zcchc8 interacts with proteins involved in RNA processing/degradation. We suggest that Zcchc8 is a GSK-3 substrate with a role in RNA metabolism.

Authors:
 [1];  [1];  [1];  [2]
  1. Divisions of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109 (United States)
  2. Divisions of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109 (United States). E-mail: bclurman@fhcrc.org
Publication Date:
OSTI Identifier:
20793233
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 338; Journal Issue: 3; Other Information: DOI: 10.1016/j.bbrc.2005.10.090; PII: S0006-291X(05)02322-3; 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; ANTIBODIES; GLYCOGEN; IN VITRO; IN VIVO; INHIBITION; LIGASES; METABOLISM; PHOSPHORYLATION; RNA; RNA PROCESSING; SUBSTRATES; THREONINE

Citation Formats

Gustafson, Michael P., Welcker, Markus, Hwang, Harry C., and Clurman, Bruce E. Zcchc8 is a glycogen synthase kinase-3 substrate that interacts with RNA-binding proteins. United States: N. p., 2005. Web. doi:10.1016/J.BBRC.2005.1.
Gustafson, Michael P., Welcker, Markus, Hwang, Harry C., & Clurman, Bruce E. Zcchc8 is a glycogen synthase kinase-3 substrate that interacts with RNA-binding proteins. United States. doi:10.1016/J.BBRC.2005.1.
Gustafson, Michael P., Welcker, Markus, Hwang, Harry C., and Clurman, Bruce E. Fri . "Zcchc8 is a glycogen synthase kinase-3 substrate that interacts with RNA-binding proteins". United States. doi:10.1016/J.BBRC.2005.1.
@article{osti_20793233,
title = {Zcchc8 is a glycogen synthase kinase-3 substrate that interacts with RNA-binding proteins},
author = {Gustafson, Michael P. and Welcker, Markus and Hwang, Harry C. and Clurman, Bruce E.},
abstractNote = {Phosphorylation of c-Myc on threonine 58 (T58) stimulates its degradation by the Fbw7-SCF ubiquitin ligase. We used a phosphorylation-specific antibody raised against the c-Myc T58 region to attempt to identify other proteins regulated by the Fbw7 pathway. We identified two predominant proteins recognized by this antibody. The first is Ebna1 binding protein 2, a nucleolar protein that, in contrast with a previous report, is likely responsible for the nucleolar staining exhibited by this antibody. The second is Zcchc8, a nuclear protein that is highly phosphorylated in cells treated with nocodazole. We show that Zcchc8 is directly phosphorylated by GSK-3 in vitro and that GSK-3 inhibition prevents Zcchc8 phosphorylation in vivo. Moreover, we found that Zcchc8 interacts with proteins involved in RNA processing/degradation. We suggest that Zcchc8 is a GSK-3 substrate with a role in RNA metabolism.},
doi = {10.1016/J.BBRC.2005.1},
journal = {Biochemical and Biophysical Research Communications},
number = 3,
volume = 338,
place = {United States},
year = {Fri Dec 23 00:00:00 EST 2005},
month = {Fri Dec 23 00:00:00 EST 2005}
}
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