Primary murine fetal liver cells were freshly isolated from day e14.5 livers and then sorted for successive differentiation stages by Ter119 and CD71 surface expression (ranging from double-negative CFU-Es to Ter-119 positive enucleated erythrocytes) [Zhang, et al. Blood. 2003 Dec 1; 102(12):3938-46]. RNA isolated from each freshly isolated, stage-sorted population was reverse-transcribed, labelled, and then hybridized onto 3' oligo Affymetrix arrays. Important erythroid specific genes as well as the proteins that regulate them were elucidated through this profiling based on coexpression and differential expression patterns as well as by extracting specific GO categories of genes (such as DNA-binding proteins).
Homeodomain-interacting protein kinase 2 plays an important role in normal terminal erythroid differentiation.
Specimen part
View SamplesThe molecular chaperone HSP90 aids the maturation of a diverse but select set of metastable protein clients, many of which are key to a variety of signal transduction pathways. HSP90 function has been best investigated in animal and fungal systems, where inhibition of the chaperone has exceptionally diverse effects, ranging from reversing oncogenic transformation to facilitating the acquisition of drug resistance. Inhibition of HSP90 in the model plant Arabidopsis thaliana uncovers novel morphologies dependent on normally cryptic genetic variation and increases stochastic variation inherent to developmental processes. The biochemical activity of HSP90 is strictly conserved between animals and plants. However, the substrates and pathways dependent on HSP90 in plants are poorly understood. Progress has been impeded by reliance on light-sensitive HSP90 inhibitors due to redundancy in the A. thaliana HSP90 gene family. Here we present phenotypic and genome-wide expression analyses of A. thaliana with constitutively reduced HSP90 levels achieved by RNAi targeting. HSP90 reduction affects a variety of quantitative life-history traits, including flowering time and total seed set, and decreases developmental stability. Further, by quantitative analysis of morphological phenotypes, we demonstrate that HSP90-reduction increases phenotypic diversity in both seedlings and adult plants. Several morphologies are synergistically affected by HSP90 and growth temperature. Genome-wide expression analyses also suggest a central role for HSP90 in the genesis and maintenance of plastic responses. The expression results are substantiated by examination of the response of HSP90-reduced plants to attack by caterpillars of the generalist herbivore Trichoplusia ni. HSP90 reduction potentiates a more robust herbivore defense response. In sum, we propose that HSP90 exerts global effects on the environmental responsiveness of plants to many different stimuli. The comprehensive set of HSP90-reduced lines described here is a vital instrument to further examine the role of HSP90 as a central interface between organism, development, and environment.
Phenotypic diversity and altered environmental plasticity in Arabidopsis thaliana with reduced Hsp90 levels.
Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The impact of microRNAs on protein output.
No sample metadata fields
View SamplesThe gene expression of two different tumorigenic human breast epithelial cell types (HMLER and BPLER) is compared with their immortalized parental cell-of-origin (HME and BPE).
Transformation of different human breast epithelial cell types leads to distinct tumor phenotypes.
Sex, Specimen part, Disease
View SamplesHuman and mouse embryonic stem cells (ESCs) are derived from blastocyst stage embryos but have very different biological properties, and molecular analyses suggest that the pluripotent state of human ESCs isolated so far corresponds to that of mouse derived epiblast stem cells (EpiSCs). Here we rewire the identity of conventional human ESCs into a more immature state that extensively shares defining features with pluripotent mouse ESCs. This was achieved by exogenous induction of Oct4, Klf4 and Klf2 factors combined with LIF and inhibitors of glycogen synthase kinase 3 (GSK3) and mitogen-activated protein kinase (ERK) pathway. Forskolin, a protein kinase A pathway agonist that induces Klf4 and Klf2 expression, can transiently substitute for the requirement for ectopib transgene expression. In contrast to conventional human ESCs, these epigenetically converted cells have growth properties, an X chromosome activation state (XaXa), a gene expression profile, and signaling pathway dependence that are highly similar to that of mouse ESCs. Finally, the same growth conditions allow the derivation of human induced pluripotent stem (iPS) cells with similar properties as mouse iPS cells. The generation of nave human ESCs will allow the molecular dissection of a previously undefined pluripotent state in humans, and may open up new opportunities for patient-specific, disease-relevant research.
Human embryonic stem cells with biological and epigenetic characteristics similar to those of mouse ESCs.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Generation of isogenic pluripotent stem cells differing exclusively at two early onset Parkinson point mutations.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Identification of human germinal center light and dark zone cells and their relationship to human B-cell lymphomas.
Specimen part
View SamplesThe EMT program allows epithelial cells to become endowed with motility, invasiveness and stem cell traits. We investigated difference in signaling networks that are differentially utilized in EMTed and non-EMTed cells, thereby identifying therapeutic targets that are unique to EMT/cancer stem cells.
Protein kinase C α is a central signaling node and therapeutic target for breast cancer stem cells.
No sample metadata fields
View SamplesPatient-specific induced pluripotent stem cells (iPSCs) derived from somatic cells provide a unique tool for the study of human disease in disease relevant cells, as well as a promising source for cell replacement therapies for degenerative diseases. However one of the crucial limitations before realizing the full promise of this disease in a dish approach has been the inability to do controlled experiments under genetically defined conditions. This is particularly relevant for disorders with long latency periods, such as Parkinsons disease (PD), where in vitro phenotypes of patient-derived iPSCs are predicted to be subtle and susceptible to significant epistatic effects of genetic background variations. By combining zinc-finger nuclease (ZFN)-mediated genome editing and iPSC technology we provide a generally applicable solution to this key problem by generating isogenic pairs of disease and control human embryonic stem cells (hESCs) and hiPSCs lines that differ exclusively at a susceptibility variant for PD by modifying a single point mutation (A53T) in the -synuclein gene. The robust capability to genetically correct disease causing point mutations in patient-derived hiPSCs represents not only a significant progress for basic biomedical research but also a major advancement towards hiPSC-based cell replacement therapies using autologous cells.
Generation of isogenic pluripotent stem cells differing exclusively at two early onset Parkinson point mutations.
Specimen part
View SamplesIdentification of genes enriched in the presumptive primary mouth. Dissected tissues from the primary mouth anlage and two other anterior regions for comparison, the anterior dorsal and ventral plus cement gland.
The Wnt antagonists Frzb-1 and Crescent locally regulate basement membrane dissolution in the developing primary mouth.
No sample metadata fields
View Samples