Phosphorylation of the Leukemic Oncoprotein EVI1 on Serine 196 Modulates DNA Binding, Transcriptional Repression and Transforming Ability

PLoS One

Brigit Greystoke¹  Tim D. Somerville¹  Tim C. P. Somervaille¹  Ruud Delwel²  Eric Bindels²  Simon Lovell³  Stefan Meyer⁴  Daniel J. White⁴  Joanne Muter⁴  Hsiang-Ying Teng⁴  John Griffiths⁴  Andrew Pierce⁴  Richard D. Unwin⁴  Anthony D. Whetton⁴ 

[1] Cancer Research UK Leukaemia Biology Laboratory, Paterson Institute of Cancer Research, Manchester, United Kingdom;Department of Hematology, Erasmus University, Rotterdam, The Netherlands;Faculty of Life Sciences, University of Manchester, Academic Health Science Centre, Manchester, United Kingdom;Stem Cell and Leukaemia Proteomics Laboratory, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom

关键词: Phosphorylation;    Zinc finger domains;    Serine;    Fibroblasts;    Transcriptional control;    DNA-binding proteins;    DNA transcription;    Immunoprecipitation;   

DOI  :  10.1371/journal.pone.0066510

学科分类：医学（综合）

来源: Public Library of Science

【 摘 要 】

The EVI1 (ecotropic viral integration site 1) gene at 3q26 codes for a transcriptional regulator with an essential role in haematopoiesis. Overexpression of EVI1 in acute myeloid leukaemia (AML) is frequently associated with 3q26 rearrangements and confers extremely poor prognosis. EVI1 mediates transcriptional regulation, signalling, and epigenetic modifications by interacting with DNA, proteins and protein complexes. To explore to what extent protein phosphorylation impacts on EVI1 functions, we analysed endogenous EVI1 protein from a high EVI1 expressing Fanconi anaemia (FA) derived AML cell line. Mass spectrometric analysis of immunoprecipitated EVI1 revealed phosphorylation at serine 196 (S196) in the sixth zinc finger of the N-terminal zinc finger domain. Mutated EVI1 with an aspartate substitution at serine 196 (S196D), which mimics serine phosphorylation of this site, exhibited reduced DNA-binding and transcriptional repression from a gene promotor selectively targeted by the N-terminal zinc finger domain. Forced expression of the S196D mutant significantly reduced EVI1 mediated transformation of Rat1 fibroblasts. While EVI1-mediated serial replating of murine haematopoietic progenitors was maintained by EVI1-S196D, this was associated with significantly higher Evi1-trancript levels compared with WT-EVI1 or EVI1-S196A, mimicking S196 non-phosphorylated EVI1. These data suggest that EVI1 function is modulated by phosphorylation of the first zinc finger domain.

【 授权许可】

CC BY