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Series GSE21367 Query DataSets for GSE21367
Status Public on Apr 20, 2010
Title The Leukemia-associated Mllt10/Af10- Dot1l, dedicated b-catenin coactivators essential for intestinal homeostasis
Organism Homo sapiens
Experiment type Expression profiling by array
Summary Background: Wnt signaling maintains the undifferentiated state of intestinal crypt progenitor cells by inducing the formation of nuclear TCF4/beta-catenin complexes. In colorectal cancer, activating mutations in Wnt pathway components cause inappropriate activation of TCF4/beta-catenin-driven transcription. Despite the passage of a decade after the discovery of TCF4 and beta-catenin as the molecular effectors of the Wnt signal, few transcriptional activators essential and unique to the regulation of this transcription program have been found.

Methodology/Principal Findings: Using proteomics, we identified the leukemia-associated Mllt10/Af10 and the methyltransferase Dot1l, as Tcf4/beta-catenin interactors in mouse small intestinal crypts. Mllt10/Af10-Dot1l, essential for transcription elongation, are recruited to Wnt target genes in a beta-catenin -dependent manner, resulting in H3K79 methylation over their coding regions in vivo in proliferative crypts of mouse small intestine, in colorectal cancer and Wnt-inducible HEK293T cells. Depletion of MLLT10/AF10 in colorectal cancer and Wnt-inducible HEK293T cells followed by expression array analysis identifies MLLT10/AF10 and DOT1L as essential activators dedicated to Wnt target gene regulation. In contrast, previously published b-catenin coactivators p300 and beta-catenin displayed a more pleiotropic target gene expression profile controlling Wnt and other pathways. tcf4, mllt10/af10 and dot1l are co-expressed in Wnt-driven tissues in zebrafish and essential for Wnt-reporter activity. Intestinal differentiation defects in apc-mutant zebrafish can be rescued by depletion of Mllt10 and Dot1l, establishing these genes as activators downstream of Apc in Wnt target gene activation in vivo. Morpholino-depletion of mllt10/af10-dot1l in zebrafish results in defects in intestinal homeostasis and a significant reduction in the in vivo expression of direct Wnt target genes and in the number of proliferative intestinal epithelial cells.

Conclusions/Significance: We conclude that Mllt10/Af10-Dot1l are essential, dedicated activators of Wnt-dependent transcription, critical for maintenance of intestinal proliferation and homeostasis. The methyltransferase Dot1l may present an attractive candidate for drug targeting in colorectal cancer.
Overall design 6 samples for Ls174T cells: si-b-catenin against si-control and dyeswap of it, si-control, si-MLLT10, si-BRG1 and si-P300 are hybridized against common reference RNA; 6 samples of HEK293T cells: Wnt3A or control medium (CM) induction for 9 hours, si-MLLT10, si-DOT1L, si-BRG1 and si-P300 upon 9 hour Wnt3A induction are all hybridized against common reference RNA
Contributor(s) Mahmoudi T, Boj SF, Hatzis P, Li VS, Taouatas N, Vries RG, Teunissen H, Begthel H, Korving J, Mohammed S, Heck AJ, Clevers H
Citation(s) 21103407
Submission date Apr 16, 2010
Last update date Mar 18, 2020
Contact name Vivian Li
Organization name The Francis Crick Institute
Lab Stem Cell and Cancer Biology
Street address 1 Midland Road
City London
ZIP/Postal code NW1 1AT
Country United Kingdom
Platforms (1)
GPL4133 Agilent-014850 Whole Human Genome Microarray 4x44K G4112F (Feature Number version)
Samples (12)
GSM533866 Ls174T si b-catenin
GSM533867 Ls174T si b-catenin (dye swap)
GSM533868 Ls174T si control
BioProject PRJNA126101

Download family Format
SOFT formatted family file(s) SOFTHelp
MINiML formatted family file(s) MINiMLHelp
Series Matrix File(s) TXTHelp

Supplementary file Size Download File type/resource
GSE21367_RAW.tar 59.4 Mb (http)(custom) TAR (of TXT)
Processed data included within Sample table

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