The biology of chronic myeloid leukemia (CML)-stem cells is still incompletely understood. Therefore, we previously developed an inducible transgenic mouse model in which stem cell targeted induction of BCR-ABL expression leads to chronic phase CML-like disease. Here, we now demonstrate that the disease is transplantable using BCR-ABL positive LSK cells (lin-Sca-1+c-kit+). Interestingly, the phenotype is enhanced when unfractionated bone marrow (BM) cells are transplanted. However, neither progenitor cells (lin-Sca-1-c-kit+) nor mature granulocytes (CD11b+Gr-1+), or potential stem cell niche cells were able to transmit the disease or alter the phenotype. The phenotype was largely independent of BCR ABL priming prior to transplant. However, BCR-ABL abrogated the potential of LSK cells to induce full blown disease in secondary recipients. Subsequently, we found that BCR-ABL increased the fraction of multipotent progenitor cells (MPP) at the expense of long term HSC (LT-HSC) in the BM. Microarray analyses of LSK cells revealed that BCR-ABL alters the expression of genes involved in proliferation, survival, and hematopoietic development. Our results suggest that BCR-ABL induces differentiation of LT-HSC and decreases their self renewal capacity. Furthermore, reversion of BCR-ABL eradicates mature cells while leukemic stem cells persist, giving rise to relapsed CML upon re-induction of BCR-ABL.
BCR-ABL enhances differentiation of long-term repopulating hematopoietic stem cells.
Specimen part
View SamplesThe subunits of voltage-gated calcium channels regulate surface expression and gating of CaV1 and CaV2 1 subunits, and thus contribute to neuronal excitability, neurotransmitter release and calcium-induced gene regulation. In addition certain subunits are targeted into the nucleus, where they directly interact with the epigenetic machinery. Whereas their involvement in this multitude of functions is reflected by a great molecular heterogeneity of isoforms derived from four genes and abundant alternative splicing, little is known about the roles of individual variants in specific neuronal functions. In the present study, an alternatively spliced 4 subunit lacking the variable N-terminus (4e) is identified. It is highly expressed in mouse cerebellum and cultured cerebellar granule cells (CGC) and modulates P/Q-type calcium currents in tsA cells and CaV2.1 surface expression in neurons. Compared to the other two known full-length 4 variants (4a, 4b) 4e is most abundantly expressed in the distal axon, but lacks nuclear targeting properties. To examine the importance of nuclear targeting of 4 subunits for transcriptional regulation, we performed whole genome expression profiling of CGCs from lethargic mice individually reconstituted with 4a, 4b, and 4e. Notably, the number of genes regulated by each 4 splice variant correlated with the rank order of their nuclear targeting properties (4b> 4a> 4e). Together these findings support isoform-specific functions of 4 splice variant in neurons, with 4b playing a dual role in channel modulation and gene regulation, while the newly detected 4e variant serves exclusively in calcium channel-dependent functions.
Differential neuronal targeting of a new and two known calcium channel β4 subunit splice variants correlates with their regulation of gene expression.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Conserved principles of mammalian transcriptional regulation revealed by RNA half-life.
No sample metadata fields
View SamplesData from tc-, nt- and p-RNA as well as 1 and 2h of actinomycin-D treatment (5g/ml) of NIH-3T3 cells used to determine half-lives. RNA was labeled for 15, 30 or 60 minutes with 4-thiouridine. After preparation of tc-RNA, thiol-labeled RNA was biotinylated using biot-HPDP and subsequently tc-RNA was separated into nt- and p-RNA using streptavidin coated magnetic beads. All three fractions were used for microarray analysis. For actinomycin-D experiments only tc-RNA was used prepared from cell before and 1 an 2h after addition of act-D.
Conserved principles of mammalian transcriptional regulation revealed by RNA half-life.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Satb1 Regulates Contactin 5 to Pattern Dendrites of a Mammalian Retinal Ganglion Cell.
Specimen part
View SamplesThe development of the epidermis, a stratified squamous epithelium, is dependent on the regulated differentiation of keratinocytes. Differentiation begins with the initiation of stratification, a process tightly controlled through proper gene expression. AP-2 is expressed in skin and previous research suggested a pathway where p63 gene induction results in increased expression of AP-2 which in turn is responsible for induction of K14. This study uses a conditional gene ablation model to further explore the role of AP-2 in skin development. Mice deficient for AP-2 exhibited delayed expression of p63, K14, and K1, key genes required for development and differentiation of the epidermis. In addition, microarray analysis of E16.5 skin revealed delayed expression of additional late epidermal differentiation genes: filaggrin, repetin and secreted Ly6/Plaur domain containing 1, in mutant mice. The genetic delay in skin development was further confirmed by a functional delay in the formation of an epidermal barrier. These results document an important role for AP-2 in skin development, and reveal the existence of regulatory factors that can compensate for AP-2 in its absence.
Disruption of epidermal specific gene expression and delayed skin development in AP-2 gamma mutant mice.
No sample metadata fields
View SamplesThe goal of this experiment was to define gene expression patterns of two mouse retinal ganglion cell subsets, labeled by expression of fluorescent proteins in Hb9-GFP and Drd4-GFP mice, all retinal ganglion cells labeled by anti-Thy1 antibody staining.
Satb1 Regulates Contactin 5 to Pattern Dendrites of a Mammalian Retinal Ganglion Cell.
Specimen part
View SamplesGene expression was analyzed in intestinal epithelial cells of germ-free and wildtype mice.
A novel role for constitutively expressed epithelial-derived chemokines as antibacterial peptides in the intestinal mucosa.
No sample metadata fields
View SamplesThe SAGA co-activator has been implicated in the regulation of a smal subset of genes in budding yeast in transcriptomic analyses performed in steady-state levels of RNA.
SAGA Is a General Cofactor for RNA Polymerase II Transcription.
Genetic information
View SamplesThe SAGA co-activator has been implicated in the regulation of a smal subset of genes in budding yeast in transcriptomic analyses performed in steady-state levels of RNA.
SAGA Is a General Cofactor for RNA Polymerase II Transcription.
Genetic information
View Samples