Project description:This SuperSeries is composed of the following subset Series: GSE24992: Drosophila brain microRNA expression with age: miRNA profiling GSE25007: Drosophila brain gene expression with age: mRNA profiling GSE25008: Drosophila brain gene expression between wildtype and miR-34 null flies Refer to individual Series. Aging is the most prominent risk factor for human neurodegenerative disease, but underlying mechanisms that connect two processes are less well characterized. With age, the brain undergoes functional decline and perhaps degeneration. Such decline may not just contribute to normal aging, but also enhance susceptibility to and progression of age-related neurodegenerative diseases. Therefore, defining intrinsic factors and pathways that underline the normal integrity of the adult nervous system may lead to insights that potentially link aging and neurodegeneration. Here, we report a highly conserved microRNA (miRNA), miR-34, as a modulator of aging and neurodegeneration. Using Drosophila, we show that fly miR-34 expression is brain-enriched and strikingly upregulated with age. Functional studies reveal that, whereas animals without miR-34 are normal as young adults, upon aging, they gradually show late-onset deficits characteristic of accelerated brain aging; these include a transcriptional signature of aged animals, coupled with rapid functional decline, loss of brain integrity, followed by a catastrophic decline in adult viability. Moreover, upregulation of miR-34 protects against neurodegeneration induced by pathogenic human polyglutamine (polyQ) disease protein. We next reveal a dramatic effect of miR-34 to silence the Eip74EF gene of steroid hormone pathways in the adult, which is crucial to maintain the normal aging. Collectively, these data define a miR-34-mediated mechanism that specifically affects long-term integrity of the adult nervous system. miR-34 function in Drosophila may thus present a link that functionally connects aging and neurodegeneration. Our studies implicate essential roles of miRNA- dependent pathways in maintenance of the adult brain, disease pathogenesis and healthy aging.
Project description:miRNA profiling was carried out using the miRCURY LNA™ microRNA Array (6th gen - hsa, mmu & rno) miRNA were profiled in amygdala brain tissue obtained from adult mice 30 mins after auditory fear conditioning and expression levels compared to tissue obtained from Home cage controls Adult male mice were fear conditioned using tone-shock pairings and brains were harvested 30 mins later. The brains of Home Cage controls and Fear Conditioned animals (n = 4/group) were then punched to collect amygdala tissue. miRNA were extracted using the Qiagen miRNeasy Kit, and then shipped to Exiqon. Exiqon performed labeling, hybridization and data analysis after use of the miRCURY LNA™ microRNA Array (6th gen - hsa, mmu & rno). https://www.exiqon.com/ls/Documents/Scientific/miRCURY-LNA-microRNA-Array-6th-gen-hsa-mmu-rno-manual.pdf
Project description:Proteomic analysis of differentially expressed proteins in MDA-MB-231 and MCF-10A cell lines when miR-200c and miR-203 were transiently expressed or inhibited, respectively.
Project description:Mature B-cell differentiation provides an important mechanism for the acquisition of adaptive immunity. Malignancies derived from mature B-cells constitute the majority of leukemias and lymphomas. These malignancies often maintain the characteristics of the normal B-cells that they are derived from, a feature that is frequently used in their diagnosis. The role of microRNAs in mature B-cells is largely unknown. Through concomitant microRNA and mRNA-profiling, we demonstrate a potential regulatory role for microRNAs at every stage of the mature B-cell differentiation process. Further, we have experimentally identified a direct role for the microRNA-regulation of key transcription factors in B-cell differentiation: LMO2 and PRDM1 (Blimp1). We also profiled microRNA of B-cell tumors derived from diffuse large B cell lymphoma, Burkitt lymphoma and chronic lymphocytic leukemia. We found that in contrast to many other malignancies, common B-cell malignancies do not down-regulate microRNAs, but rather maintain the microRNA-expression patterns of their normal B-cell counterparts. Further, each tumor-type maintained the expression of the lineage-specific microRNAs and expression of these lineage-specific microRNAs could correctly predict the lineage of B-cell malignancies in over 90% of the cases. Thus, our data demonstrate that microRNAs may be important in maintaining the mature B-cell phenotype in normal and malignant B-cells. Burkitt lymphoma, Chronic Lymphocytic Leukemia (Mutated), Chronic Lymphocytic Leukemia (Unmutated), Activated B cell-like Diffuse large B cell lymphoma, and Germinal Center-like Diffuse large B cell lymphoma Samples,
Project description:Amyotrophic Lateral Sclerosis is clinically defined as the combined degeneration of the corticospinal and corticobulbar neurons (CSN) along with the bulbar and spinal motor neurons (SMN). While a growing body of evidence points to the motor cortex, where CSN are located, as the potential initiation site of ALS, little is known about how CSN degenerate. To gain insights into the molecular mechanisms behind CSN selective degeneration, we first developed an approach to purify this neuronal population from the cerebral cortex of adult wild-type and Sod1G86R mice, combining retrograde labelling and Fluorescence Activated Cell Sorting. In parallel, a second population of cortical neurons, the callosal projection neurons (CPN) located in the layers II/III of the cerebral cortex were also purified. CPN and CSN are both cortical excitatory projection neurons but as opposed to CSN, CPN do not degenerate in Sod1G86R mice, and served as control population. CSN and CPN were purified from same animals, at two presymptomatic ages (3 and 60 days) and two symptomatic ages, 90 and 105 days. A total of 57 samples were further processed and analysed (CSN: 30d: n=4 WT and 3 Sod1G86R; 60d: n=4 WT and 4 Sod1G86R; 90d: n=4 WT and 4 Sod1G86R; 105d: n=4 WT and 2 Sod1G86R; CPN: 30d: n=4 WT and 3 Sod1G86R; 60d: n=2 WT and 3 Sod1G86R; 90d: n=4 WT and 4 Sod1G86R; 105d: n=4 WT and 4 Sod1G86R).
Project description:We compared repeatability and comparability of microRNA microarray using 5 different platforms. and compared microarray data generated from five different microRNA microarray platforms with quantitative RT-PCR. Our data suggested that the most accurate and repeatable methods for microRNA expression profiling are Agilent and Toray, and the numbers of detected microRNA at Toray are more than at Agilent. Keywords: repeatability, comparability, microRNA, microarray We compared repeatability and comparability of microRNA microarray using 5 different platforms (Agilent, Ambion, Exiqon, Invitrogen, and Toray). In addition, we compared microarray data generated from five different microRNA microarray platforms with quantitative RT-PCR.
Project description:Once Haemonchus contortus infects sheep it receives a series of host attacks, especially those relating to the infected animal’s T lymphocytes immune response. To obtain a systematic genome-wide profiling of the T lymphocyte genes involved, microarrays were used to compare gene expression between 0 days post infection (dpi), 3-5 dpi, 25-30 dpi and 60dpi in infected sheep. In this 853, 242 and 42 differentially expressed genes were acquired in the 3d vs. 0d comparison, the 30d vs. 0d comparison and the 60d vs. 0d comparison, respectively. Gene Ontology and pathway analysis indicated that modulated genes including SUGT1, FCER1G, CD23, IL-13 and galectin-14, were mostly associated with cellular homeostasis maintaining and immune response.