Upregulation of pro-apoptotic microRNA mir-125a following massive small bowel resection in rats
ABSTRACT: Upregulation of mir-125a suppresses the pro-survival protein Mcl1, producing the increase in apoptosis known to accompany the proliferative changes characteristic of intestinal adaptation. Our data highlight a potential role for microRNAs as mediators of the adaptive process and may facilitate the development of new therapeutic options for short bowel syndrome. Overall design: Two-condition experiment: resected rat jejunum vs. pooled transected control, with dye-swaps.
Project description:Upregulation of mir-125a suppresses the pro-survival protein Mcl1, producing the increase in apoptosis known to accompany the proliferative changes characteristic of intestinal adaptation. Our data highlight a potential role for microRNAs as mediators of the adaptive process and may facilitate the development of new therapeutic options for short bowel syndrome. Two-condition experiment: resected rat jejunum vs. pooled transected control, with dye-swaps.
Project description:Hematopoietic stem/progenitor cell (HSPC) traits differ between genetically distinct mouse strains. For example, DBA/2 mice have a higher HSPC frequency compared to C57BL/6 mice. We performed a genetic screen for microRNAs that are differentially expressed between LSK, LS−K+, erythroid and myeloid cells isolated from C57BL/6 and DBA/2 mice. This analysis identified 131 microRNAs that were differentially expressed between cell types and 15 that were differentially expressed between mouse strains. Of special interest was an evolutionary conserved miR-cluster located on chromosome 17 consisting of miR-99b, let-7e and miR-125a. All cluster members were most highly expressed in LSKs and down-regulated upon differentiation. In addition, these microRNAs were higher expressed in DBA/2 cells compared to C57BL/6 cells, and thus correlated with HSPC frequency. To functionally characterize these microRNAs, we overexpressed the entire miR-cluster 99b/let-7e/125a and miR-125a alone in BM cells from C57BL/6 mice. Overexpression of the miR-cluster or miR-125a dramatically increased day-35 CAFC activity and caused severe hematopoietic phenotypes upon transplantation. We showed that a single member of the miR-cluster, namely miR-125a, is responsible for the majority of the observed miR-cluster overexpression effects. Finally, we performed genome-wide gene expression arrays and identified candidate target genes through which miR-125a may modulate HSPC fate. These data consist of total mRNA obtained from 7-day cultured post 5-FU BM cells positively transduced with empty vector, miR-cluster 99b/let-7e/125a, miR-125a or miR-155 retroviral vector. Dataset (A) and dataset (B) were analyzed individualy. In each dataset, all samples were analyzed in independent biological triplicates.
Project description:miR-125a knockout mice develop myeloproliferative disorder (MPD). To investigate the molecular mechanisms of MPD induced by the loss of miR-125a, gene expression profiling on hematopoietic stem cells of miR-125a (+/+), (+/-) MPD, and (-/-) MPD mice was performed by using CodeLinkTM Whole Genome DNA array analysis. CodeLink Mouse Whole Genome Bioarrays were performed according to the manufacturer’s instruction on total RNA extracted from hematopoietic stem cells of miR-125a (+/+) wild-type mouse, miR-125a (+/-) heterozygous mouse with MPD, and miR-125a (-/-) homozygous mouse with MPD. One replicate per array.
Project description:miR-125a knockout mice develop myeloproliferave disorder (MPD). To investigate the molecular mechanisms of MPD induced by the loss of miR-125a, gene expression profiling on hematopoietic stem cells of miR-125a (+/+) and (+/-) MPD mice was performed using CodeLink Whole Genome DNA array analysis. Codelink Mouse Whole Genome Bioarrays were performed according to the manufacturer’s instruction on total RNA extracted from hematopoietic stem cells of miR-125a (+/+) wild-type mice and miR-125a (+/-) heterozygous mice with MPD. One replicate per array.
Project description:Mutant genotype miR-125a precurrsor was found in recurrent pregnancy loss patients. We use RIP-chip assay to detect the disturbed mRNA profiling in RISC of HEK293T cells after wildtype or mutant genotype miR-125a expression vector transfection.
Project description:We found miR-125a was a key regulator that stabilizes the commitment and immunoregulatory capacity of Treg cells.To gain insights into the general functional features of miR-125a-deficient Treg cells, we performed a genome-wide gene array analysis on Treg population isolated from the spleens of 6 to 8-week-old miR-125a-deficient and WT mice We sorted CD4+CD25hi Treg population from the spleens of 6 to 8-week-old miR-125a-deficient and their littermate WT mice. Cells were collected and total RNA was extracted for Affymetrix GeneChip®Mouse Genome 430 2.0 Array
Project description:Systemic juvenile idiopathic arthritis (SJIA) is a severe childhood arthropathy with features of autoinflammation. Monocytes and macrophages in SJIA have a complex phenotype with both pro- and anti-inflammatory properties that combine features of several well characterized in vitro conditions used to activate macrophages. An important anti-inflammatory phenotype is expression of CD163, a scavenger receptor that sequesters toxic pro-inflammatory complexes that is highly expressed in both active SJIA and macrophage activation syndrome (MAS). CD163 is most strongly upregulated by IL-10 (M(IL-10)), and not by other conditions that reflect features seen in SJIA monocytes such as M(LPS+IC). MicroRNA play key roles balancing and integrating cellular signals such as those in macrophage polarization, and as such we hypothesize microRNA regulate macrophage functional responses in SJIA including CD163 expression in vitro. We find that two microRNA previously found to be elevated in active SJIA, miR-125a-5p and miR-181c, significantly reduced macrophage CD163 expression through two distinct mechanisms. Neither microRNA was elevated in M(IL-10) with robust CD163 expression, but were instead induced in M(LPS+IC) where they restricted CD163 mRNA expression. Mir-181 species directly targeted CD163 mRNA for degradation. In contrast, transcriptome analysis of miR-125a-5p overexpression identified “cytokine-cytokine receptor interactions” as the most significantly repressed gene pathway, including decreased IL10RA, which is required for IL-10-mediated CD163 expression. Finally, overexpression of miR-181c inhibited CD163 anti-inflammatory responses to hemoglobin or high mobility group box 1 complexes. Together, these data show that microRNA utilize multiple mechanisms to integrate well characterized polarization phenotypes and regulate macrophage functional properties seen in SJIA. Overall design: THP-1 human monocytic cells were transfected in triplicate with negative control microRNA mimic or miR-125a-5p mimic. RNA extracted 24hours after transfection
Project description:This SuperSeries is composed of the following subset Series: GSE33689: Expression profiles of HSPCs overexpressing microRNA cluster 99b/let-7e/125a, miR-125a, miR-155 and empty vector. GSE33690: MicroRNA profiles of four developmentally related hematopoietic cell types isolated from the BM of B6 and D2 mice. Refer to individual Series
Project description:Neutrophil activation plays a critical role in the inflammatory response to gram-negative bacterial infections. Lipopolysaccharide (LPS) from gram-negative bacterial has been shown to be a major mediator of neutrophil activation to produce pro-inflammatory cytokines, chemokines and ROS which are important to tissue damage in LPS induced septic shock. We used microarrays to detail the global gene expression of neutrophils from miR-125a+/+ and miR-125a-/- mice after LPS stimulation. Overall design: Bone marrow neutrophils from miR-125a deficient and wild type mice were enriched by magnetic beads, then stimulated without or with LPS for 3 hours and harvested in Trizol . Extracted RNAs from three independent experiments were pooled for hybridization on Affymetrix microarrays.
Project description:Cullin 4B (CUL4B), a scaffold protein that assembles CRL4B ubiquitin ligase complexes, has been reported to be overexpressed in several types of solid tumors and contributes to epigenetic silencing of tumor suppressor. However, its clinical significance and the molecular mechanisms underlying its regulation in gastric cancer (GC) remain largely unknown. Here, we showed that CUL4B was elevated in GC tissues and its overexpression was positively correlated with poor prognosis and lymph node metastasis. CUL4B knockdown in GC cells decreased proliferation, mesenchymal transition and invasion in vitro, as well as tumor growth and metastasis in nude mice, and CUL4B overexpression induced the opposite results. Further studies showed that miR-101 could inhibit CUL4B expression by directly targeting its 3’-UTR and they were inversely correlated in clinical GC specimens. Notably, a positive relationship between CUL4B and HER2 was found in GC clinical specimens, GC cells and GC xenograft tumors. Through bioinformatics analysis of miRNA-seq data and target prediction, we nominated miR-125a as a direct target of CUL4B. ChIP assays demonstrated that CUL4B directly repressed miR-125a expression by physically binding to its promoter. In addition, we confirmed miR-125a is the target of HER2. Consequently, we demonstrated that CUL4B can up-regulate HER2 expression through repressing miR-125a. Most importantly, silencing of HER2 by Herceptin or siRNA partially reversed CUL4B-induced epithelial-to-mesenchymal transition (EMT), cell invasion and metastasis in vitro and in vivo. These findings define a CUL4B-miR-125a-HER2 regulatory mechanism shed light on CUL4B oncogenic mechanisms and reveals promising therapeutic targets for progressive GC. CUL4B proteins are frequently upregulated in human cancer, yet little is known about the underlying molecular mechanisms of CUL4B induced gastric cancer(GC) carcigenesis.Here, we uncover the critical role of CUL4B in gastric cancer growth and metastasis through the regulation of HER2 expression.CUL4B contributes to GC invasion and metastasis by transcriptional repression of HER2 targeting miR-125a, which provide a new insight into how CUL4B regulates GC progression and metastasis. Overall design: A two chip study using total RNA recovered from MKN45 gastric cancer cells transfected with negative control(NC) or siRNA silencing CUL4B (si4B) for 48hs. Each chip measures the expression 27,958 genes were collected from the authoritative data source including NCBI.