RESEARCH ARTICLE
Armadillo Repeat Containing 8α Binds to HRS and Promotes HRS Interaction with Ubiquitinated Proteins
Koji Tomaru1, Atsuhisa Ueda*, 1, Takeyuki Suzuki1, Nobuaki Kobayashi1, Jun Yang1, Masaki Yamamoto1, Mitsuhiro Takeno1, Takeshi Kaneko2, Yoshiaki Ishigatsubo1
Article Information
Identifiers and Pagination:
Year: 2010Volume: 4
First Page: 1
Last Page: 8
Publisher ID: TOBIOCJ-4-1
DOI: 10.2174/1874091X01004010001
Article History:
Received Date: 30/10/2009Revision Received Date: 30/11/2009
Acceptance Date: 10/12/2009
Electronic publication date: 13/1/2010
Collection year: 2010

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http: //creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Abstract
Recently, we reported that a complex with an essential role in the degradation of Fructose-1,6-bisphosphatase in yeast is well conserved in mammalian cells; we named this mammalian complex C-terminal to the Lissencephaly type-1-like homology (CTLH) complex. Although the function of the CTLH complex remains unclear, here we used yeast two-hybrid screening to isolate Hepatocyte growth factor-regulated tyrosine kinase substrate (HRS) as a protein binding to a key component of CTLH complex, Armadillo repeat containing 8 (ARMc8) α. The association was confirmed by a yeast two-hybrid assay and a co-immunoprecipitation assay. The proline-rich domain of HRS was essential for the association. As demonstrated through immunofluorescence microscopy, ARMc8α co-localized with HRS. ARMc8α promoted the interaction of HRS with various ubiquitinated proteins through the ubiquitin-interacting motif. These findings suggest that HRS mediates protein endosomal trafficking partly through its interaction with ARMc8α.