Format

Send to

Choose Destination
See comment in PubMed Commons below
Exp Cell Res. 2013 Oct 15;319(17):2554-65. doi: 10.1016/j.yexcr.2013.09.001. Epub 2013 Sep 11.

The translation initiation factor 3 subunit eIF3K interacts with PML and associates with PML nuclear bodies.

Author information

1
Department of Pathology, Dalhousie University, P.O. Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.

Abstract

The promyelocytic leukemia protein (PML) is a tumor suppressor protein that regulates a variety of important cellular processes, including gene expression, DNA repair and cell fate decisions. Integral to its function is the ability of PML to form nuclear bodies (NBs) that serve as hubs for the interaction and modification of over 90 cellular proteins. There are seven canonical isoforms of PML, which encode diverse C-termini generated by alternative pre-mRNA splicing. Recruitment of specific cellular proteins to PML NBs is mediated by protein-protein interactions with individual PML isoforms. Using a yeast two-hybrid screen employing peptide sequences unique to PML isoform I (PML-I), we identified an interaction with the eukaryotic initiation factor 3 subunit K (eIF3K), and in the process identified a novel eIF3K isoform, which we term eIF3K-2. We further demonstrate that eIF3K and PML interact both in vitro via pull-down assays, as well as in vivo within human cells by co-immunoprecipitation and co-immunofluorescence. In addition, eIF3K isoform 2 (eIF3K-2) colocalizes to PML bodies, particularly those enriched in PML-I, while eIF3K isoform 1 associates poorly with PML NBs. Thus, we report eIF3K as the first known subunit of the eIF3 translation pre-initiation complex to interact directly with the PML protein, and provide data implicating alternative splicing of both PML and eIF3K as a possible regulatory mechanism for eIF3K localization at PML NBs.

KEYWORDS:

Light microscopy; Nuclear structure; PML; Yeast two-hybrid; eIF3K

PMID:
24036361
DOI:
10.1016/j.yexcr.2013.09.001
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center