Summary: Melanoma spheroids grown under neural crest cell conditions are highly plastic migratory/invasive tumor cells endowed with immunomodulator function
Melanoma spheroids grown under neural crest cell conditions are highly plastic migratory/invasive tumor cells endowed with immunomodulator function.
No sample metadata fields
View SamplesWe used the flu mutant of Arabidopsis and a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX) to address the interactions between different reactive oxygen species (ROS) signaling pathways. The conditional flu mutant of Arabidopsis accumulates excess protochlorophyllide in the dark within chloroplast membranes that upon illumination acts as a photosensitizer and generates singlet oxygen (1O2). Immediately after the release of singlet oxygen rapid changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by other reactive oxygen species, superoxide or hydrogen peroxide (H2O2), suggesting that different types of active oxygen species activate distinct signaling pathways. It was not known whether the pathways operate separately or interact with each other. We have addressed this problem by modulating noninvasively the level of H2O2 in plastids by means of a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX, line 14/2 PMID: 15165186). In the flu mutant overexpressing tAPX, the expression of most of the nuclear genes that were rapidly activated after the release of 1O2 was significantly higher in flu plants overexpressing tAPX, whereas in wild-type plants, overexpression of tAPX had only a very minor impact on nuclear gene expression. The results suggest that H2O2 antagonizes the 1O2-mediated signaling of stress responses as seen in the flu mutant. This cross-talk between H2O2- and 1O2-dependent signaling pathways might contribute to the overall stability and robustness of wild-type plants exposed to adverse environmental stress conditions.
Cross-talk between singlet oxygen- and hydrogen peroxide-dependent signaling of stress responses in Arabidopsis thaliana.
No sample metadata fields
View SamplesThe exit of antigen-presenting cells (APC) and lymphocytes from inflamed skin to afferent lymph is vital for the initiation and maintenance of dermal immune responses. How such exit is achieved and how cells transmigrate the distinct endothelium of lymphatic vessels is however unknown. Here we show that inflammatory cytokines trigger activation of dermal lymphatic endothelial cells (LEC) leading to expression of the key leukocyte adhesion receptors ICAM-1, VCAM-1 and E-selectin, as well as a discrete panel of chemokines and other potential regulators of leukocyte transmigration. Furthermore, we show that both ICAM-1 and VCAM-1 are induced in the dermal lymphatic vessels of mice exposed to skin contact hypersensitivity where they mediate lymph node trafficking of DC via afferent lymphatics. Lastly, we show that TNF_-stimulates both DC adhesion and transmigration of dermal LEC monolayers in vitro and that the process is efficiently inhibited by ICAM-1 and VCAM-1 adhesion-blocking mAbs. These results reveal a CAM-mediated mechanism for recruiting leukocytes to the lymph nodes in inflammation and highlight the process of lymphatic transmigration as a potential new target for anti-inflammatory therapy.
An inflammation-induced mechanism for leukocyte transmigration across lymphatic vessel endothelium.
No sample metadata fields
View SamplesHuman SH-SY5Y neuroblastoma cells are widely utilized in in vitro studies to dissect out pathogenetic mechanisms of neurodegenerative disorders. These cells are considered as neuronal precursors and differentiate into more mature neuronal phenotypes under selected growth conditions. In this study, we performed systematic transcriptomic (RNA-seq) and bioinformatic analysis to pinpoint pathways and cellular processes underlying neuronal differentiation of SH-SY5Y cells according to a two-step paradigm: retinoic acid treatment followed by enriched neurobasal medium. Categorization of 1989 differentially expressed genes (DEGs) identified in differentiated cells outlined meaningful biological functions associated with changes in cell morphology including remodelling of plasma membrane and cytoskeleton, neuritogenesis. Seventy-three DEGs were assigned to Axonal Guidance Signalling pathway, and the expression of selected gene products such as neurotrophin receptors, the functionally related SLITRK6, and semaphorins, was validated by immunoblotting. Along with these findings, the differentiated cells exhibited the ability to elongate longer axonal process as assessed by the morphometric evaluation. Recognition of molecular events occurring in differentiated SH-SY5Y cells is necessary to accurately interpret the cellular responses to specific stimuli in studies on disease pathogenesis. Overall design: Comparison of cell line SH-SY5Y differentiated and undifferentiated.
Transcriptomic Profiling Discloses Molecular and Cellular Events Related to Neuronal Differentiation in SH-SY5Y Neuroblastoma Cells.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Conserved molecular interactions within the HBO1 acetyltransferase complexes regulate cell proliferation.
Specimen part, Cell line, Treatment
View SamplesWe find that 499 genes are up-regulated and 457 are down-regulated in response to over-expression of JADE1, while 397 genes are up-regulated and 385 are down-regulated after HBO1 knock-down.
Conserved molecular interactions within the HBO1 acetyltransferase complexes regulate cell proliferation.
Cell line, Treatment
View SamplesWe used the flu mutant of Arabidopsis to detail gene expression in response to singlet oxygen. The conditional flu mutant of Arabidopsis accumulates excess protochlorophyllide in the dark within chloroplast membranes that upon illumination acts as a photosensitizer and generates singlet oxygen. Immediately after the release of singlet oxygen mature flu plants stop growing, whereas seedlings bleach and die. Within the first 30 min after the release of singlet oxygen rapid changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by other reactive oxygen species, superoxide or hydrogen peroxide.
Rapid induction of distinct stress responses after the release of singlet oxygen in Arabidopsis.
No sample metadata fields
View SamplesWe used microarrays to detail Arabidopsis gene expression in response to paraquat, a herbicide that acts as a terminal oxidant of photosystem I that in the light leads to the enhanced generation of superoxide and hydrogen peroxide inside plastids. Within a few hours after paraquat treatment changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by another reactive oxygen species, singlet oxygen.
Rapid induction of distinct stress responses after the release of singlet oxygen in Arabidopsis.
No sample metadata fields
View SamplesThe Bromo-domain and PHD-finger protein, BRPF3, forms a complex with HBO1 and regulates the initiation of DNA replication. BRPF3-dependent histone H3K14 enriched in chromatin surrounding a fraction of replication origins may play an important role in origin firing.
BRPF3-HBO1 regulates replication origin activation and histone H3K14 acetylation.
Cell line, Treatment
View SamplesThe thorough characterization of the transcriptome of endogenous podocytes has been hampered by low yields of cell isolation procedures. Here we introduce a double fluorescent reporter mouse model combined with an optimized bead perfusion protocol and efficient single cell dissociation yielding more than 500,000 podocytes per mouse allowing for global, unbiased downstream applications. Combining mRNA transcriptional profiling revealed programs of highly specific gene regulation tightly controlling cytoskeleton, cell differentiation, endosomal transport and peroxisome function in podocytes. Strikingly, the analyses further predict that these podocyte-specific gene regulatory networks are accompanied by alternative splicing of respective genes. In summary, the presented omics approach will facilitate the discovery and integration of novel gene, protein and organelle regulatory networks that deepen our systematic understanding of podocyte biology.
Molecular fingerprinting of the podocyte reveals novel gene and protein regulatory networks.
Specimen part
View Samples