Identification of novel Notch target genes in T cell leukaemia.
BACKGROUND
Dysregulated Notch signalling is believed to play an important role in the development and maintenance of T cell leukaemia. At a cellular level, Notch signalling promotes proliferation and inhibits apoptosis of T cell acute lymphoblastic leukaemia (T-ALL) cells. In this study we aimed to identify novel transcriptional targets of Notch signalling in the T-ALL cell line, Jurkat.


RESULTS
RNA was prepared from Jurkat cells retrovirally transduced with an empty vector (GFP-alone) or vectors containing constitutively active forms of Notch (N1DeltaE or N3DeltaE), and used for Affymetrix microarray analysis. A subset of genes found to be regulated by Notch was chosen for real-time PCR validation and in some cases, validation at the protein level, using several Notch-transduced T-ALL and non-T-ALL leukaemic cell lines. As expected, several known transcriptional target of Notch, such as HES1 and Deltex, were found to be overexpressed in Notch-transduced cells, however, many novel transcriptional targets of Notch signalling were identified using this approach. These included the T cell costimulatory molecule CD28, the anti-apoptotic protein GIMAP5, and inhibitor of DNA binding 1 (1D1).


CONCLUSIONS
The identification of such downstream Notch target genes provides insights into the mechanisms of Notch function in T cell leukaemia, and may help identify novel therapeutic targets in this disease.
Chadwick
Nicholas
N
Faculty of Life Sciences, Manchester Interdisciplinary Biocenter, University of Manchester, Manchester, UK. n.chadwick@manchester.ac.uk
Zeef
Leo
L
Portillo
Virginia
V
Fennessy
Carl
C
Warrander
Fiona
F
Hoyle
Sarah
S
Buckle
Anne-Marie
AM
D018106:CD28 Antigens / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D005434:Flow Cytometry; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D051798:Inhibitor of Differentiation Protein 1 / Q000235:genetics / Q000378:metabolism; D019169:Jurkat Cells; D015458:Leukemia, T-Cell / Q000235:genetics* / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D051880:Receptors, Notch / Q000235:genetics* / Q000378:metabolism; D015203:Reproducibility of Results; D015398:Signal Transduction / Q000235:genetics*; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
D018106:CD28 Antigens; C497453:ID1 protein, human; D051798:Inhibitor of Differentiation Protein 1; D051880:Receptors, Notch; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D020558:GTP Phosphohydrolases