This SuperSeries is composed of the SubSeries listed below.
5-hydroxymethylcytosine marks promoters in colon that resist DNA hypermethylation in cancer.
Sex, Specimen part, Cell line, Treatment, Subject
View SamplesThe discovery of cytosine hydroxymethylation (5-hmC) as a mechanism that potentially controls DNA methylation changes typical of neoplasia prompted us to investigate its behavior in colon cancer. 5-hmC is globally reduced in proliferating cells such as colon tumors and the gut crypt progenitors, from which tumors can arise. Here, we show that colorectal tumors and cancer cells express Ten-Eleven Translocation (TET) transcripts at levels similar to normal tissues. Genome-wide analyses show that promoters marked by 5-hmC in normal tissue, and those identified as TET2 targets in colorectal cancer cells, are resistant to methylation gain in cancer. In vitro studies of TET2 in cancer cells confirm that these promoters are resistant to methylation gain independently of sustained TET2 expression. We also find that a considerable number of the methylation gain-resistant promoters marked by 5-hmC in normal colon overlap with those that are marked with poised bivalent histone modifications in embryonic stem cells. Together our results indicate that promoters that acquire 5-hmC upon normal colon differentiation are innately resistant to neoplastic hypermethylation by mechanisms that do not require high levels of 5-hmC in tumors. Our study highlights the potential of cytosine modifications as biomarkers of cancerous cell proliferation.
5-hydroxymethylcytosine marks promoters in colon that resist DNA hypermethylation in cancer.
Sex, Specimen part, Subject
View SamplesDuring vertebrate retinogenesis, the precise balance between retinoblast proliferation and differentiation is spatially and temporally regulated through a number of intrinsic factors and extrinsic signaling pathways. Moreover, there are complex gene regulatory network interactions between these intrinsic factors and extrinsic pathways, which ultimately function to determine when retinoblasts exit the cell cycle and terminally differentiate. We recently uncovered a cell non-autonomous role for the intrinsic HLH factor, Id2a, in regulating retinoblast proliferation and differentiation, with Id2a-deficient retinae containing an abundance of proliferative retinoblasts and an absence of terminally differentiated retinal neurons and glia. Here, we report that Id2a function is necessary and sufficient to limit Notch pathway activity during retinogenesis. Id2a-deficient retinae possess elevated levels of Notch pathway component gene expression, while retinae overexpressing id2a possess reduced expression of Notch pathway component genes. Attenuation of Notch signaling activity by DAPT or by morpholino knockdown of Notch1a is sufficient to rescue both the proliferative and differentiation defects in Id2a-deficient retinae. In addition to regulating Notch pathway activity, through an RNA-Seq and differential gene expression analysis of Id2a-deficient retinae, we identify a number of additional intrinsic and extrinsic regulatory pathway components whose expression is regulated by Id2a. These data highlight the integral role played by Id2a in the gene regulatory network governing the transition from retinoblast proliferation to terminal differentiation during vertebrate retinogenesis. Overall design: Two biological replicates for both Id2aMM and Id2aMO samples
Id2a functions to limit Notch pathway activity and thereby influence the transition from proliferation to differentiation of retinoblasts during zebrafish retinogenesis.
No sample metadata fields
View SamplesBackground
Gene expression profile of cervical and skin tissues from human papillomavirus type 16 E6 transgenic mice.
No sample metadata fields
View SamplesCopper-based chemotherapeutic compounds Casiopeinas, have been presented as able to promote selective programmed cell death in cancer cells, thus being proper candidates for targeted cancer therapy. DNA fragmentation and apoptosis -in a process mediated by reactive oxygen species- for a number of tumor cells, have been argued to be the main mechanisms. However, a detailed functional mechanism (a model) is still to be defined and interrogated for a wide variety of cellular conditions; before establishing settings and parameters needed for their wide clinical application.
Whole genome gene expression analysis reveals casiopeína-induced apoptosis pathways.
Cell line
View SamplesSeed germination is a critical developmental process in plant propagation. Knowledge of the gene expression patterns in this critical process is important in order to understand the main biochemical reactions involved in successful germination, specially for economically relevant plants such as Maize.
Expression profile of maize (Zea mays L.) embryonic axes during germination: translational regulation of ribosomal protein mRNAs.
Treatment, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The Small Molecule Hyperphyllin Enhances Leaf Formation Rate and Mimics Shoot Meristem Integrity Defects Associated with AMP1 Deficiency.
Specimen part, Treatment
View SamplesMany bacterial pathogens of plants and humans cause infections by delivering effector proteins into host cells. Elucidation of how pathogen effector proteins function not only is critical for understanding bacterial pathogenesis, but also provides an important tool in discovering the functions of host genes. In this study, we characterized the Pseudomonas syringae pv. tomato DC3000 effector AvrE, the founding member of a widely distributed, yet functionally enigmatic, bacterial effector family. We show that AvrE is localized in the plasma membrane (PM) and PM-associated vesicle-like structures in the plant cell. AvrE contains two physically interacting domains, and the N terminal portion contains a plasma membrane localization signal. Genome-wide microarray analysis indicates that AvrE, as well as a functionally-redundant effector HopM1, down-regulates the expression of the NDR1/HIN1-Like 13 gene in Arabidopsis. Mutational analysis shows that NHL13 is required for plant immunity, as the nhl13 mutant plant displayed enhanced disease susceptibility. Our results defined the site of action of one of the most important bacterial virulence proteins in plants and the anti-bacterial immunity function of the NHL13 gene.
Pseudomonas syringae Effector Avirulence Protein E Localizes to the Host Plasma Membrane and Down-Regulates the Expression of the NONRACE-SPECIFIC DISEASE RESISTANCE1/HARPIN-INDUCED1-LIKE13 Gene Required for Antibacterial Immunity in Arabidopsis.
Specimen part, Treatment
View SamplesALTERED MERISTEM PROGRAM1 (AMP1) is a member of the M28 family of carboxypeptidases with a pivotal role in plant development and stress adaptation. Its most prominent mutant defect is a unique hypertrophic shoot phenotype combining a strongly increased organ formation rate with enhanced meristem size and the formation of ectopic meristem poles. However, so far the role of AMP1 in shoot development could not be assigned to a specific molecular pathway nor is its biochemical function resolved. We used a chemical genetic approach to identify the drug hyperphyllin (HP), which specifically mimics the shoot defects of amp1, including plastochron reduction and enlargement and multiplication of the shoot meristem. To further assess whether hyperphyllin acts in an AMP1-dependent manner we compared the transcriptonal responses of hyperphyllin-treated wild-type and amp1 mutant seedlings.
The Small Molecule Hyperphyllin Enhances Leaf Formation Rate and Mimics Shoot Meristem Integrity Defects Associated with AMP1 Deficiency.
Specimen part, Treatment
View SamplesALTERED MERISTEM PROGRAM1 (AMP1) is a member of the M28 family of carboxypeptidases with a pivotal role in plant development and stress adaptation. Its most prominent mutant defect is a unique hypertrophic shoot phenotype combining a strongly increased organ formation rate with enhanced meristem size and the formation of ectopic meristem poles. However, so far the role of AMP1 in shoot development could not be assigned to a specific molecular pathway nor is its biochemical function resolved. We used a chemical genetic approach to identify the drug hyperphyllin (HP), which specifically mimics the shoot defects of amp1, including plastochron reduction and enlargement and multiplication of the shoot meristem. To further assess whether hyperphyllin acts in an AMP1-dependent manner we compared the transcriptonal responses of hyperphyllin-treated wild-type Arabidopsis seedlings with those of untreated amp1 mutant seedlings.
The Small Molecule Hyperphyllin Enhances Leaf Formation Rate and Mimics Shoot Meristem Integrity Defects Associated with AMP1 Deficiency.
Specimen part, Treatment
View Samples