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SRP090853
Homo sapiens
6 Downloadable Samples
Illumina HiSeq 2000
Description
The NEET proteins mitoNEET (mNT) and nutrient-deprivation autophagy factor-1 (NAF-1) are required for cancer cell proliferation and resistance to oxidative stress. MitoNEET and NAF-1 are also implicated in a number of other human pathologies including diabetes, neurodegeneration and heart disease, as well as in development, differentiation and aging. Previous studies suggested that mNT and NAF-1 could function in the same pathway in cancer cells, preventing the over-accumulation of iron and reactive oxygen species (ROS) in mitochondria. Nevertheless, it is unknown whether these two proteins interact in cells, and how they mediate their function. Here we demonstrate, using yeast two-hybrid, in vivo bimolecular fluorescence complementation (BiFC), direct coupling analysis (DCA), RNA- sequencing, ROS and iron imaging, and single and double shRNA lines with suppressed mNT, NAF-1 and mNT/NAF-1 expression, that mNT and NAF-1 interact in cancer cells and function in the same cellular pathway. We further show using an in vitro cluster transfer assay that mNT can transfer its clusters to NAF-1. Our study suggests that mNT and NAF-1 could function as part of an iron-sulfur (2Fe-2S) cluster relay to maintain the levels of iron and Fe-S clusters under control in the mitochondria of cancer cells, thereby preventing the activation of apoptosis and/or autophagy and thus promoting rapid cellular proliferation. Overall design: Examination of the effect of suppression of mNT in the breast cancer cell line MCF-7. Two sample types were analyzed, MCF-7 suppressed for mNT and MCF-7 Empty vector control, three replicates for each.
Publication Title
Interactions between mitoNEET and NAF-1 in cells.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 6 Downloadable Samples
- IlluminaHiSeq2000
Description
Nutrient autophagy factor 1 (NAF-1) is an iron-sulfur protein found on the outer mitochondrial membrane and the ER. Recent studies highlighted an important role for NAF-1 in regulating autophagy via interaction with BCL-2. We recently reported that the level of NAF-1 is elevated in cancer cells and that NAF-1 is required for tumor growth. Here we report that shRNA suppression of NAF-1 results in the activation of apoptosis in xenograft tumors and cancer cells grown in culture. Suppression of NAF-1 resulted in a depletion in the cytosolic iron pool, facilitated uptake of iron, and accumulation of iron and ROS in mitochondria, a shift to glycolysis and glutaminolysis, and the activation of cellular stress pathways associated with HIF1a, AMPK and mTOR. Suppression of NAF-1 in breast cancer cells appears therefore to reduce their tumorigenicity by interfering with cellular iron distribution and energy metabolism resulting in the activation of apoptosis. Overall design: Examination of the effect of suppression of NAF-1 in the breast cancer cell line MCF-7. Two sample types were analyzed, MCF-7 suppressed for NAF-1 and MCF-7 Empty vector control, three replicates for each.
Publication Title
Activation of apoptosis in NAF-1-deficient human epithelial breast cancer cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 30 Downloadable Samples
Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Low-dose radiation affects cardiac physiology: gene networks and molecular signaling in cardiomyocytes.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
We examined molecular responses using transcriptome profiling in isolated left ventricular murine cardiomyocytes to 90 cGy, 1 GeV proton (1H) and 15 cGy, 1 GeV/nucleon (n) iron (56Fe) particles 1, 3, 7, 14 and 28 days after exposure. Unsupervised clustering analysis of gene expression segregated samples according to the radiation (IR) response, and time after exposure with 56Fe-IR showing the greatest level of gene modulation. 1H-IR exposures showed little differential transcript modulation. Network analysis categorized the major differentially expressed genes into cell cycle, oxidative responses and transcriptional regulation functional groups. Transcriptional networks identified key nodes regulating expression. Individual transcription factors were inferred to be active at 1, 3, 7, 14 and 28 days after exposure. Validation of the signal transduction network by protein analysis showed that particle IR clearly regulates a long lived signaling mechanism for p38 MAPK signaling and NFATc4 activation. Electrophoresis mobility shift assays supported the role of additional key transcription factors GATA-4, STAT-3 and NF-B as regulators of the response at specific time points. These data suggest that the molecular response to 56Fe-IR is unique and shows long-lasting gene expression in cardiomyocytes, up to 28 days after exposure. Additionally, proteins involved in signal transduction and transcriptional activation via DNA binding play a role in the response to high charge (Z) and energy (E) particles (HZE). Our study may have implications for NASAs efforts to develop heart disease risk estimates for astronauts safety via identification of specific HZE-IR molecular markers and for patients receiving conventional and particle radiotherapy.
Publication Title
Low-dose radiation affects cardiac physiology: gene networks and molecular signaling in cardiomyocytes.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 36 Downloadable Samples
- Illumina HiSeq 2500
Description
We discovered a rare missense mutation in NR1H4 (R436H), which encodes the farnesoid X receptor (FXR), associating with lower levels of total cholesterol in the Icelandic population. To explore the effects of R436H we used CRISPR-Cas9 to generate homozygous NR1H4 R436H and NR1H4 knockout human iPSC lines which we differentiated to hepatocytes. Hepatocytes were treated with an FXR agonist for 24 hours and transcript abundance measured by RNA-seq. The global response to FXR activation in NR1H4 R436H cells was very similar to that of wild-type cells showing that it is not a loss-of-function mutation. However, we did observe subtle gene expression differences compatible with an effect on lipids when we compared R436H agonist treated hepatocytes to wild-type agonist treated hepatocytes. Overall design: RNA-seq was performed on wild-type, NR1H4 knockout and NR1H4 R436H iPSC-derived hepatocytes treated with FXR agonist GW4064.
Publication Title
Predicted loss and gain of function mutations in ACO1 are associated with erythropoiesis.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples