Project description:We developed a new method to extract open-chromatins that contain trans-acting factors (TAFs)-DNA complex crosslinked with dithiobis(succinimidyl propionate) (DSP). Using this method we identified CBFB as a cell density-sensitive TAF, which translocates between the cytoplasm and the nucleus in cell density-dependent manner. Here, we demonstrate that the extracted TAF/DNA complex is also amenable to ChIP-seq analysis.
Project description:Background—YAP, the nuclear effector of Hippo signaling, regulates cellular growth and survival in multiple organs, including the heart, by interacting with TEAD sequence specific DNA-binding proteins. Recent studies showed that YAP stimulates cardiomyocyte proliferation and survival. However, the direct transcriptional targets through which YAP exerts its effects are poorly defined. Methods and Results—To identify genes directly regulated by YAP in cardiomyocytes, we combined differential gene expression analysis in YAP gain- and loss-of-function with genome-wide identification of YAP bound loci using chromatin immunoprecipitation and high throughput sequencing. This screen identified Pik3cb, encoding p110β, a catalytic subunit of phosphoinositol-3-kinase (PI3K), as a candidate YAP effector that promotes cardiomyocyte proliferation and survival. We validated YAP and TEAD occupancy of a conserved enhancer within the first intron of Pik3cb, and show that this enhancer drives YAP-dependent reporter gene expression. Yap gain- and loss-of-function studies indicated that YAP is necessary and sufficient to activate the PI3K-Akt pathway. Like Yap, Pik3cb gain-of-function stimulated cardiomyocyte proliferation, and Pik3cb knockdown dampened the YAP mitogenic activity. Reciprocally, Yap loss-of-function impaired heart function and reduced cardiomyocyte proliferation and survival, all of which were significantly rescued by AAV-mediated Pik3cb expression. Conclusion—Pik3cb is a crucial direct target of YAP, through which the YAP activates PI3K-AKT pathway and regulates cardiomyocyte proliferation and survival. Yap wild type ChIPseq and input
Project description:It is known that CBFB-MYH11, the fusion gene generated by inversion of chromosome 16 in human acute myeloid leukemia, is causative for oncogenic transformation. However, the mechanism by which CBFB-MYH11 initiates leukemogenesis is not clear. Previously published reports showed that CBFB-MYH11 dominantly inhibits RUNX1 and CBFB, and such inhibition has been suggested as the mechanism for leukemogenesis. However, knockin mice expressing Cbfb-MYH11 (Cbfb+/MYH11) showed defects in primitive hematopoiesis not seen in Cbfb null (Cbfb-/-) embryos indicating that Cbfb-MYH11 has repression independent activities as well. To identify gene expression changes associated with this novel activity, we compared the gene expression profile in the blood cells of Cbfb+/MYH11 and Cbfb-/- embryonic day 12.5 (E12.5) embryos with that of their wildtype littermates. Cbfb-MYH11 chimeras were mated to C57/Bl6 females to generate Cbfb+/MYH11 (Cbfb+/MYH11) and Cbfb+/+ (WT) embryos. Cbfb+/- x Cbfb+/- matings were used to generate Cbfb+/+ (Cbfb+/+) and Cbfb-/- (Cbfb-/-) embryos. Blood from 8-10 E12.5 embryos of the same genotype was pooled, and RNA was isolated, labeled, and hybridized to Affymetrix Genechip mouse microarray (430 2.0) chips. 4 chips were used for both the Cbfb+/MYH11 and littermate control samples. 3 chips were used for the Cbfb-/- samples and littermate control samples.
Project description:It is known that CBFB-MYH11, the fusion gene generated by inversion of chromosome 16 in human acute myeloid leukemia, is causative for oncogenic transformation. However, the mechanism by which CBFB-MYH11 initiates leukemogenesis is not clear. Previously published reports showed that CBFB-MYH11 dominantly inhibits RUNX1 and CBFB, and such inhibition has been suggested as the mechanism for leukemogenesis. However, knockin mice expressing Cbfb-MYH11 (Cbfb+/MYH11) showed defects in primitive hematopoiesis not seen in Cbfb null (Cbfb-/-) embryos indicating that Cbfb-MYH11 has repression independent activities as well. To identify gene expression changes associated with this novel activity, we compared the gene expression profile in the blood cells of Cbfb+/MYH11 and Cbfb-/- embryonic day 12.5 (E12.5) embryos with that of their wildtype littermates.
Project description:Results showed that Chd7 deficiency delay Cbfb-MYH11 induced leukemia, to explore the mechanism, We also performed microarray analysis on c-Kit+ leukemic cells to determine gene expression differences between Mx1-Cre, Cbfb+/56M and Chd7f/f, Mx1-Cre, Cbfb+/56M leukemic cells.
Project description:Runx/Cbfb heterodimers play important roles in the development of hematopoietic cells in mouse embryos and adults. In order to identify genes that are regulated by Runx/Cbfb, we purified Lin– c-kit+ Sca1+ (LSK) cells and Lin– c-kit+ Sca1– CD16/32+ (GMP) cells from Vav1-iCre x Cbfb(F/F) and Vav1-iCre x Cbfb(F/+) mice and profiled gene expression using microarray.
Project description:To identify the target genes of Runx1/Cbfb in MLL fusion leukemia, we performed microarray analysis using control and Runx1/Cbfb-deleted MLL-AF9 cells.