MicroRNA-222 Attenuates Mitochondrial Dysfunction Induced by Transmissible Gastroenteritis Virus via Targeting Thrombospondin-1 and Inhibiting Cluster of Differentiation 47
ABSTRACT: Transmissible gastroenteritis virus (TGEV) is a member of Coronaviridae family. Our previous research showed that TGEV infection could induce mitochondrial dysfunction and up-regulat miR-222 level. Therefore, we presumed that miR-222 might be implicated in regulating mitochondrial dysfunction induced by TGEV infection. To verify the hypothesis, the effect of miR-222 on mitochondrial dysfunction was detected and showed that miR-222 attenuated TGEV-induced mitochondrial dysfunction. To investigate the underlying molecular mechanism of miR-222 in TGEV-induced mitochondrial dysfunction, a quantitative proteomic analysis of PK-15 cells that were transfected with miR-222 mimics and infected with TGEV was performed. In total, 4151 proteins were quantified and 100 differentially expressed proteins were obtained (57 up-regulated, 43 down-regulated), among which thrombospondin-1 (THBS1) and cluster of differentiation 47 (CD47) were down-regulated. THBS1 was identified as the target of miR-222. Knockdown of THBS1 and CD47 increased mitochondrial Ca2+ level and decreased mitochondrial membrane potential (MMP) level. Together, our data establish a significant role of miR-222 in regulating mitochondrial dysfunction in response to TGEV infection.
Project description:Transmissible gastroenteritis virus (TGEV), a member of the coronaviridae family, could cause fatal diarrhea of piglets and result in numerous economic losses. Previous studies demonstrated that TGEV infection could lead to mitochondrial damage and up-regulate miR-4331 level. So miR-4331 may play an important regulatory role in the control of mitochondrial function. To explore the potential role of miR-4331 in mitochondrial damage, we adopted a strategy consisting of quantitative proteomic analysis of porcine kidney (PK-15) cells in response to miR-4331 and TGEV infection. Eventually, 69 differentially expressed proteins were gained. The target of miR-4331 was identified. The effects of miR-4331 and its target RB1 on mitochondrial Ca2+ level, mitochondrial membrane potential (MMP), interleukin-1 receptor accessory protein (IL1RAP), p38 MAPK signaling pathway were investigated. The results showed that miR-4331 elevated mitochondrial Ca2+ level, reduced MMP, targets Retinoblastoma 1 (RB1), up-regulated IL1RAP, and induced activation of p38 MAPK pathway during TGEV infection. RB1 was identified as the direct targets of miR-4331 and down-regulated IL1RAP, suppressed the activation of p38 MPAK, and attenuated TGEV-induced mitochondrial damage. In addition, IL1RAP played a positive role in activating p38 MAPK signaling and negative role in TGEV-induced mitochondrial damage. The data indicate that miR-4331 aggravates TGEV-induced mitochondrial damage by repressing expression of RB1, promoting IL1RAP, and activating p38 MAPK pathway.
Project description:Melphalan-induced modulation of miR-221/222 levels in MM cells. Melphalan-resistant U266/LR7 cells showed the highest induction of miR-221/222 after drug exposure. To study the transcriptome perturbation induced in MM cells following the combination of miR-221/222 inhibitors plus melphalan we used the whole gene expression data total RNA was obtained after single or combination treatment of the Melphalan-resistant U266/LR7 cells and the parental cell line U266/s
Project description:To evaluate involvement of miR-221 and miR-222 in lung cancer, we investigated the effects of miR-221 and miR-222 overexpression on six lung cancer cell lines as well as one immortalized normal human bronchial epithelial cell line. Two cell lines, H3255 and H1299 with no replicates were studied. Cells were transfected with miR-221, miR-222, or miR control. Microarray analysis was done to identify genes differentially expressed in lung cancer cells after the transfection of miR-221 or miR-222.
Project description:A number of microRNAs have been shown to regulate skeletal muscle development and differentiation. MicroRNA-222 is downregulated during myogenic differentiation and its overexpression leads to alteration of muscle differentiation process and specialized structures. By using RNA induced silencing complex (RISC) pulldown followed by RNA sequencing, combined with in silico microRNA target prediction, we have identified two new targets of microRNA-222 involved in the regulation of myogenic differentiation, Ahnak and Rbm24. Specifically, the RNA binding protein Rbm24 is a major regulator of muscle specific alternative splicing and its downregulation by microRNA-222 results in defective exon inclusion impairing the production of muscle-specific isoforms of Coro6, Fxr1 and NACA transcripts. Reconstitution of normal levels of Rbm24 in cells overexpressing microRNA-222 rescues muscle-specific splicing. In conclusion, we have identified a new function of microRNA-222 leading to alteration of myogenic differentiation at the level of alternative splicing, and we provide evidence that this effect is mediated by Rbm24 protein. We built linear models using 2 different experiments and two conditions (miR222 over expression (n=1) and control siRNA(n=2)) with the linear formula (~condition + experiment).
Project description:To explore the role of miR-22 in the heart, we generated miR-22 null and transgenic mice. Absence of miR-22 results in partial embryonic lethality arising from cardiac malformations. miR-22-null mice that survived until adulthood showed normal cardiac structure and function at baseline but were sensitized to cardiac dysfunction and dilation following pressure overload stimulation. Absence of miR-22 prevented the induction of beta-myosin heavy chain (Myh7) and miR-208b expression following pathologic stress. miR-22 null animals were also compromised in cardiac expression of Myh7b and miR-499. We found that miR-22 directly regulates two transcriptional antagonists, purine rich element binding protein B (PURB), a repressor, and serum response factor (SRF), an activator, in the heart. Through these gain- and loss-of-function experiments in mice, we suggest that a primary function of miR-22 is to fine tune the relative expression and activity of these two transcriptional antagonists to influence contractile gene expression, function, growth and adaptation of the heart to stress.
Project description:MiR-142 is upregulated in neurons in HIV and SIV encephalitis. We have created stable clones of the BE(2)M17 human neuroblastoma cell line overexpressing miR-142. Gene expression in these miR-142-expressing clones was compared to stable clones transfected with control miR-null in order to identify miR-142 targets relevant to neuronal dysfunction in HIV encephalitis. RNA was extracted from 3 independent miR-142-expressing clones (6B, 6C, 6G) and 3 independent miR-null expressing clones (1A, 2A, 2B) for expression analysis. Partek genomics suite was used for data analysis. Genes that had fold change > -2.5 and p <0.001 were chosen for validation by RT-PCR
Project description:Colorectal cancer (CRC) is the third most common cancer worldwide. Colorectal polyps are recognised pre-cursors of CRC, however hyperplastic polyps lack malignant potential. The purpose of this study was to identify differences in gene expression between normal colonic mucosa, hyperplastic and adenomatous polyps from disease-free individuals. By comparing polyps believed to have malignant potential (adenomatous polyps) with hyperplastic polyps it is hoped that new insights into colorectal carcinogenesis can be achieved. 24 colonic samples comprising 8 normal colonic mucosa, 8 hyperplastic polyps and 8 adenomatous polyps.