Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

HeLa cell mitochondrial microRNAs

ABSTRACT: MicroRNAs (miRNAs) are small non-coding RNAs that associate with Argonaute 2 protein to regulate gene expression at the post-transcriptional level in the cytoplasm. However, recent studies have reported that some miRNAs localize to and function in other cellular compartments. Mitochondria harbour their own genetic system that may be a potential site for miRNA-mediated post-transcriptional regulation. We aimed at investigating whether nuclear-encoded miRNAs can localize to and function in human mitochondria. To enable identification of mitochondrial-enriched miRNAs, we profiled the mitochondrial and cytosolic RNA fractions from the same HeLa cells by miRNA microarray analysis. Mitochondria were purified using a combination of cell fractionation and immunoisolation, and assessed for the lack of protein and RNA contaminants. We found 57 miRNAs differentially expressed in HeLa mitochondria and cytosol. Of these 57, a signature of 13 nuclear-encoded miRNAs was reproducibly enriched in mitochondrial RNA and validated by RT-PCR for hsa-miR-494, hsa-miR-1275 and hsa-miR-1974. This study provides the first comprehensive view of the localization of RNA interference components to the mitochondria. Our data outline the molecular bases for a novel layer of crosstalk between nucleus and mitochondria through a specific subset of human miRNAs that we termed ‘mitomiRs’. To assess whether nuclear-encoded miRNA are detectable in human mitochondria, we performed the following four steps approach. First, cultured HeLa cells were allowed to reach 80-100% confluence and subjected to fractionation in order to isolate the cytosolic fraction. From the same HeLa cells, mitochondria were isolated by immunomagnetic Anti-TOM22 MicroBeads from the Mitochondria Isolation Kit (Miltenyi Biotec). In total, six mitochondria preparations were perfromed, three of these were additionally treated with RNase A. Second, total RNA was extracted from the mitochondrial and cytosolic fractions. Third, mitochondrial and cytosolic RNA were respectively profiled by microRNA microarray analysis. Last, data were analyzed and normalized.Three independent assays were performed.

ORGANISM(S): Homo sapiens

SUBMITTER: Silvia Rueberg

PROVIDER: E-GEOD-24761 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Nuclear outsourcing of RNA interference components to human mitochondria.

Bandiera Simonetta S Rüberg Silvia S Girard Muriel M Cagnard Nicolas N Hanein Sylvain S Chrétien Dominique D Munnich Arnold A Lyonnet Stanislas S Henrion-Caude Alexandra A

PloS one 20110613 6

MicroRNAs (miRNAs) are small non-coding RNAs that associate with Argonaute proteins to regulate gene expression at the post-transcriptional level in the cytoplasm. However, recent studies have reported that some miRNAs localize to and function in other cellular compartments. Mitochondria harbour their own genetic system that may be a potential site for miRNA mediated post-transcriptional regulation. We aimed at investigating whether nuclear-encoded miRNAs can localize to and function in human mi ...[more]

PMID: 21695135

Similar Datasets

Project description:Background MicroRNAs are important regulators of transcription in hematopoiesis. Their expression deregulations were described in association with pathogenesis of some hematological malignancies. This study provides integrated microRNA expression profiling at different phases of chronic myeloid leukemia (CML) with the aim to select CML specific miRNAs and find new possible biomarkers. The functions of in silico filtered targets are in this report annotated and discussed in relation to CML pathogenesis. Results Using microarrays we identified differential expression profiles of 49 miRNAs in CML patients at diagnosis, in hematological relapse, therapy failure, blast crisis and major molecular response. The expression deregulation of miR-150, miR-20a, miR-17, miR-19a, miR-103, miR-144, miR-155, miR-181a, miR-221 and miR-222 in CML was confirmed by real-time quantitative PCR and in silico analyses identified targeted genes of these miRNAs encoding proteins that are involved in cell cycle, growth inhibition, MAPK, ErBb, transforming growth factor beta and p53 signaling pathways that are related to CML. Validated miR-150 decreased levels were detected in patients at diagnosis, in blast crisis and 67% of hematological relapses and showed significant negative correlation with miR-150 proved target MYB and with BCR-ABL transcript level. Conclusions This study revealed microRNAs that may be related to the CML pathogenesis and may reflect transformation from chronic to accelerated phases. The obtained expression patterns in peripheral blood total leukocytes during the course of CML suggest specific miRNAs as possible biomarkers. The annotated functions of in silico filtered targets of selected miRNAs outline mechanisms whereby microRNAs may be involved in CML pathogenesis. Twenty four patient samples of total leukocytes from peripheral blood were used to prepare pools representing different CML phases for microarray analysis: diagnosis (n=5, Dg), major molecular response (n=5, MMR), therapy failure (n=5, TF), hematological relapse (n=5, Hr), and blast crisis (n=4, BC). Eleven healthy donors of age median 60 (range 45 - 78) and man/woman ratio 3/2 following CML incidence were used to create a control pool.

Project description:The subpopulations of mesenchymal stem cells isolated from breast adipose tissue which display migrated towards conditioned media from MDA-MB231 cell line were expanded for miRNA analysis. The tumor microenvironment (TM) is known to promote tumor growth and progression. Ubiquitously distributed tissue resident stem cells (MSCs) elicit regenerative properties. In addition, they are capable of homing to sites of inflammation, injury, and tumor. Considering the tumor tropic property of MSCs, the interaction between the breast cancer (BC) microenvironment and breast resident adipose tissue derived MSCs (ASCs) merits further investigations. Initial data indicate that a subset of ASCs derived from breast adipose tissue (B-ASCs) display a high affinity towards the conditioned media (CM) from two breast cancer cell lines, MDA-MB231 (MDA-CM) and MCF7 (MCF-CM). Profiling secreted cytokines of these CMs identified significant expression of angiogenin, GM-CSF, and IL-6. While the expression of GRO-M-NM-1, MCP-1, RANTES, and IL-1M-NM-1 is more pronounced in MDA-CM, MCF-CM contains higher amounts of IGFBP2, TRAIL, and ErbB3. Gene expression profiling suggests that despite the distinct differences, both migratory subset of B-ASCs towards MDA-CM and MCF-CM display perturbed expression of genes like KISS1, TNSF1, IL18 and MMP2, which could be associated with a defensive role of B-ASCs. In addition, the BC microenvironment alters microRNA (miRNA) expressions in B-ASCs. in this study the migratory cells were evaluated for miRNA expression versus non-migratory counterparts. as controls unexposed parental cell lines (2) were used on the same hybridization chip in which one labeled Hy3 and other labeled Hy5. The ratio of the control parental cells was used as base nanalysis of miRNA expression in MSCs. we also include another control in this study, the migratory subpopulations of MSCs which display migratory potentials against protein gradient (M5) were analyzed for miRNA expression versus non-migratory counterparts (NM-5). using this control facilitate identification of those miRNA responsive to tumor CM. the data analysis confirm that altered gene and miRNA profiles resulted from exposure of MCF-CM and MDA-CM on B-ASCs are similar to those observed in B-ASCs isolated from breast adipose tissue of BC patients. Analysis the signaling between the B-ASCs and TM may help in understanding the possible role of B-ASCs in stasis, progression, or regression of the BC. The microRNA expression of migratory subpopulations were compared to parental populations of MSCs.

Project description:The COP9 signalosome (CSN) is a conserved protein complex occurring in all eukaryotes. The mammalian CSN consists of eight subunits (CSN1 – CSN8) and possesses an intrinsic metalloprotease JAMM motif localised to CSN5. In addition, it is associated with kinases such as protein kinase CK2 and D and the ubiquitin (Ub) specific protease 15. It regulates cullin-RING Ub ligases (CRLs) that label proteins for proteolysis with poly-Ub chains in the Ub proteasome system (UPS). CRLs contain one of the scaffolding cullins 1 – 7, a RING domain protein e. g. Rbx1, and one of hundreds of substrate binding units such as F-box or BTB proteins that specifically target proteins for ubiquitination. The CSN forms functional supercomplexes with CRLs. It removes the Ub-like protein Nedd8 from cullins by its metalloprotease activity and thereby inactivates CRLs. On the other hand, it is essential for CRL function by protecting components and allowing reassembly of the complexes. As a regulator of the UPS the CSN is involved in cell cycle10, DNA repair and development. Overexpression of CSN subunits has been reported in tumour cells. Up to date nothing is known about CSN biogenesis and its regulation. Ten years ago we have observed that overexpression of selected CSN subunits caused a coordinated increase of all CSN subunits and a de novo biosynthesis of the entire complex. Here we show that overexpression of CSN1 mediates an increase of c-Myc which coordinates CSN subunit expression via microRNAs (miRNAs). miRNAs are evolutionarily conserved, endogenous, small, noncoding RNA molecules of about 22 nucleotides that function as posttranscriptional gene regulators. We found that inhibitors of let-7 family miRNAs or upregulation of c-Myc, which represses let-7 miRNAs, resulted in a coordinated increase of CSN subunits and de novo CSN biogenesis. Keywords: Gene expression analysis of human RNA samples using topic-defined PIQOR™ Ubiquitin-PS Microarrays. Two different platforms were used (these are two different microarray batches which are identical in terms of the spotted cDNAs, but differ in the position of some cDNAs) Gene expression analysis of Hela cells overexpressing either CSN2 or CSN1 was performed to study CSN biogenesis and its regulation. Curcumin, Nr. 8 (Curcumin analogon) and Piceatannol were used for the treatment of Hela cells since they inhibit the CSN associated kinases. The aim was to investigate the effect on the signalosome. For each treatment 50 µM Curcumin, Nr. 8 and Piceatannol were used.

Dataset Information

HeLa cell mitochondrial microRNAs

Publications

Nuclear outsourcing of RNA interference components to human mitochondria.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure