Altered CELF1 binding to target transcripts in malignant T cells.
RNA
; 21(10): 1757-69, 2015 Oct.
Article
em En
| MEDLINE
| ID: mdl-26249002
ABSTRACT
The RNA-binding protein, CELF1, binds to a regulatory sequence known as the GU-rich element (GRE) and controls a network of mRNA transcripts that regulate cellular activation, proliferation, and apoptosis. We performed immunoprecipitation using an anti-CELF1 antibody, followed by identification of copurified transcripts using microarrays. We found that CELF1 is bound to a distinct set of target transcripts in the H9 and Jurkat malignant T-cell lines, compared with primary human T cells. CELF1 was not phosphorylated in resting normal T cells, but in malignant T cells, phosphorylation of CELF1 correlated with its inability to bind to GRE-containing mRNAs that served as CELF1 targets in normal T cells. Lack of binding by CELF1 to these mRNAs in malignant T cells correlated with stabilization and increased expression of these transcripts. Several of these GRE-containing transcripts that encode regulators of cell growth were also stabilized and up-regulated in primary tumor cells from patients with T-cell acute lymphoblastic leukemia. Interestingly, transcripts encoding numerous suppressors of cell proliferation that served as targets of CELF1 in malignant T cells, but not normal T cells, exhibited accelerated degradation and reduced expression in malignant compared with normal T cells, consistent with the known function of CELF1 to mediate degradation of bound transcripts. Overall, CELF1 dysfunction in malignant T cells led to the up-regulation of a subset of GRE-containing transcripts that promote cell growth and down-regulation of another subset that suppress cell growth, producing a net effect that would drive a malignant phenotype.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
RNA Mensageiro
/
Linfócitos T
/
Leucemia-Linfoma Linfoblástico de Células T Precursoras
/
Proteínas CELF1
Limite:
Humans
Idioma:
En
Revista:
RNA
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Estados Unidos