Identification and characterization of a nuclear localization signal of TRIM28 that overlaps with the HP1 box

Tetsuji Moriyama; Percival Sangel; Hiroki Yamaguchi; Chikashi Obuse; Yoichi Miyamoto; Masahiro Oka; Yoshihiro Yoneda

doi:10.1016/j.bbrc.2015.04.108

Identification and characterization of a nuclear localization signal of TRIM28 that overlaps with the HP1 box

Biochem Biophys Res Commun. 2015 Jul 3;462(3):201-7. doi: 10.1016/j.bbrc.2015.04.108. Epub 2015 May 7.

Authors

Tetsuji Moriyama¹, Percival Sangel¹, Hiroki Yamaguchi², Chikashi Obuse³, Yoichi Miyamoto¹, Masahiro Oka⁴, Yoshihiro Yoneda⁵

Affiliations

¹ Laboratory of Nuclear Transport Dynamics, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan.
² School of Medicine, Osaka University, Osaka 565-0871, Japan.
³ Graduate School of Life Science, Hokkaido University, Sapporo 001-0021, Japan.
⁴ Laboratory of Nuclear Transport Dynamics, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan; Laboratory of Biomedical Innovation, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka 565-0871, Japan. Electronic address: moka@nibiohn.go.jp.
⁵ National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan; Laboratory of Biomedical Innovation, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka 565-0871, Japan. Electronic address: y-yoneda@nibiohn.go.jp.

PMID: 25960296
DOI: 10.1016/j.bbrc.2015.04.108

Abstract

Tripartite motif-containing 28 (TRIM28) is a transcription regulator, which forms a repressor complex containing heterochromatin protein 1 (HP1). Here, we report identification of a nuclear localization signal (NLS) within the 462-494 amino acid region of TRIM28 that overlaps with its HP1 binding site, HP1 box. GST-pulldown experiments revealed the interaction of the arginine-rich TRIM28 NLS with various importin α subtypes (α1, α2 and α4). In vitro transport assay demonstrated that nuclear localization of GFP-TRIM28 NLS is mediated by importin αs, in conjunction with importin β1 and Ran. Further, we demonstrated that HP1 and importin αs compete for binding to TRIM28. Together, our findings suggest that importin α has an essential role in the nuclear delivery and preferential HP1 interaction of TRIM28.

Keywords: HP1; Importin α; KAP1; NLS; TIF1β; TRIM28.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Active Transport, Cell Nucleus
Amino Acid Sequence
Binding Sites
Chromobox Protein Homolog 5
Chromosomal Proteins, Non-Histone / chemistry*
Chromosomal Proteins, Non-Histone / genetics
Chromosomal Proteins, Non-Histone / metabolism*
HeLa Cells
Humans
Models, Biological
Molecular Sequence Data
Nuclear Localization Signals / chemistry*
Nuclear Localization Signals / genetics
Nuclear Localization Signals / metabolism*
Protein Binding
Protein Interaction Domains and Motifs
Recombinant Fusion Proteins / chemistry
Recombinant Fusion Proteins / genetics
Recombinant Fusion Proteins / metabolism
Repressor Proteins / chemistry*
Repressor Proteins / genetics
Repressor Proteins / metabolism*
Tripartite Motif-Containing Protein 28
alpha Karyopherins / chemistry
alpha Karyopherins / classification
alpha Karyopherins / metabolism
beta Karyopherins / chemistry
beta Karyopherins / classification
beta Karyopherins / metabolism

Substances

Chromosomal Proteins, Non-Histone
Nuclear Localization Signals
Recombinant Fusion Proteins
Repressor Proteins
alpha Karyopherins
beta Karyopherins
Chromobox Protein Homolog 5
TRIM28 protein, human
Tripartite Motif-Containing Protein 28