scholarly journals Micro-RNA Clusters Integrate Evolutionary Constraints on Expression and Target Affinities: The miR-6/5/4/286/3/309 Cluster in Drosophila

2020 ◽  
Vol 37 (10) ◽  
pp. 2955-2965
Author(s):  
Qu Zhe ◽  
Wing Chung Yiu ◽  
Ho Yin Yip ◽  
Wenyan Nong ◽  
Clare W C Yu ◽  
...  

Abstract A striking feature of micro-RNAs is that they are often clustered in the genomes of animals. The functional and evolutionary consequences of this clustering remain obscure. Here, we investigated a micro-RNA cluster miR-6/5/4/286/3/309 that is conserved across drosophilid lineages. Small RNA sequencing revealed expression of this micro-RNA cluster in Drosophila melanogaster leg discs, and conditional overexpression of the whole cluster resulted in leg appendage shortening. Transgenic overexpression lines expressing different combinations of micro-RNA cluster members were also constructed. Expression of individual micro-RNAs from the cluster resulted in a normal wild-type phenotype, but either the expression of several ancient micro-RNAs together (miR-5/4/286/3/309) or more recently evolved clustered micro-RNAs (miR-6-1/2/3) can recapitulate the phenotypes generated by the whole-cluster overexpression. Screening of transgenic fly lines revealed downregulation of leg-patterning gene cassettes in generation of the leg-shortening phenotype. Furthermore, cell transfection with different combinations of micro-RNA cluster members revealed a suite of downstream genes targeted by all cluster members, as well as complements of targets that are unique for distinct micro-RNAs. Considered together, the micro-RNA targets and the evolutionary ages of each micro-RNA in the cluster demonstrate the importance of micro-RNA clustering, where new members can reinforce and modify the selection forces on both the cluster regulation and the gene regulatory network of existing micro-RNAs. Key words: micro-RNA, cluster, evolution.

2019 ◽  
Author(s):  
Zhe Qu ◽  
Wing Chung Yiu ◽  
Ho Yin Yip ◽  
Wenyan Nong ◽  
Clare W.C. Yu ◽  
...  

AbstractA striking feature of microRNAs is that they are often clustered in the genomes of animals. The functional and evolutionary consequences of this clustering remain obscure. Here, we investigated a microRNA cluster miR-6/5/4/286/3/309 that is conserved across drosophilid lineages. Small RNA sequencing revealed expression of this microRNA cluster in Drosophila melanogaster leg discs, and conditional overexpression of the whole cluster resulted in leg appendage shortening. Transgenic overexpression lines expressing different combinations of microRNA cluster members were also constructed. Expression of individual microRNAs from the cluster resulted in a normal wild-type phenotype, but either the expression of several ancient microRNAs together (miR-5/4/286/3/309) or more recently evolved clustered microRNAs (miR-6-1/2/3) can recapitulate the phenotypes generated by the whole-cluster overexpression. Screening of transgenic fly lines revealed down-regulation of leg patterning gene cassettes in generation of the leg-shortening phenotype. Furthermore, cell transfection with different combinations of microRNA cluster members revealed a suite of downstream genes targeted by all cluster members, as well as complements of targets that are unique for distinct microRNAs. Considering together the microRNA targets and the evolutionary ages of each microRNA in the cluster demonstrates the importance of microRNA clustering, where new members can reinforce and modify the selection forces on both the cluster regulation and the gene regulatory network of existing microRNAs.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wenrui Duan ◽  
Shirley Tang ◽  
Li Gao ◽  
Kathleen Dotts ◽  
Andrew Fink ◽  
...  

AbstractThe Fanconi Anemia (FA) pathway is essential for human cells to maintain genomic integrity following DNA damage. This pathway is involved in repairing damaged DNA through homologous recombination. Cancers with a defective FA pathway are expected to be more sensitive to cross-link based therapy or PARP inhibitors. To evaluate downstream effectors of the FA pathway, we studied the expression of 734 different micro RNAs (miRNA) using NanoString nCounter miRNA array in two FA defective lung cancer cells and matched control cells, along with two lung tumors and matched non-tumor tissue samples that were deficient in the FA pathway. Selected miRNA expression was validated with real-time PCR analysis. Among 734 different miRNAs, a cluster of microRNAs were found to be up-regulated including an important cancer related micro RNA, miR-200C. MiRNA-200C has been reported as a negative regulator of epithelial-mesenchymal transition (EMT) and inhibits cell migration and invasion by promoting the upregulation of E-cadherin through targeting ZEB1 and ZEB2 transcription factors. miRNA-200C was increased in the FA defective lung cancers as compared to controls. AmpliSeq analysis showed significant reduction in ZEB1 and ZEB2 mRNA expression. Our findings indicate the miRNA-200C potentially play a very important role in FA pathway downstream regulation.


2006 ◽  
Vol 74 (1) ◽  
pp. 537-548 ◽  
Author(s):  
Rocío Canals ◽  
Natalia Jiménez ◽  
Silvia Vilches ◽  
Miguel Regué ◽  
Susana Merino ◽  
...  

ABSTRACT Mesophilic Aeromonas hydrophila strains of serotype O34 typically express smooth lipopolysaccharide (LPS) on their surface. A single mutation in the gene that codes for UDP N-acetylgalactosamine 4-epimerase (gne) confers the O− phenotype (LPS without O-antigen molecules) on a strain in serotypes O18 and O34, but not in serotypes O1 and O2. The gne gene is present in all the mesophilic Aeromonas strains tested. No changes were observed for the LPS core in a gne mutant from A. hydrophila strain AH-3 (serotype O34). O34 antigen LPS contains N-acetylgalactosamine, while no such sugar residue forms part of the LPS core from A. hydrophila AH-3. Some of the pathogenic features of A. hydrophila AH-3 gne mutants are drastically reduced (serum resistance or adhesion to Hep-2 cells), and the gne mutants are less virulent for fish and mice compared to the wild-type strain. Strain AH-3, like other mesophilic Aeromonas strains, possess two kinds of flagella, and the absence of O34 antigen molecules by gne mutation in this strain reduced motility without any effect on the biogenesis of both polar and lateral flagella. The reintroduction of the single wild-type gne gene in the corresponding mutants completely restored the wild-type phenotype (presence of smooth LPS) independently of the O wild-type serotype, restored the virulence of the wild-type strain, and restored motility (either swimming or swarming).


Author(s):  
Duong Ngoc Diem Nguyen ◽  
William M Chilian ◽  
Shamsul Mohd Zain ◽  
Muhammad Fauzi Daud ◽  
Yuh Fen Pung

Cardiovascular disease (CVD) is among the leading causes of death worldwide. Micro-RNAs (miRNAs), regulatory molecules that repress protein expression, have attracted considerable attention in CVD research. The vasculature plays a big role in CVD development and progression and dysregulation of vascular cells underlies the root of many vascular diseases. This review provides a brief introduction of the biogenesis of miRNAs and exosomes, followed by overview of the regulatory mechanisms of miRNAs in vascular smooth muscle cells (VSMCs) intracellular signaling during phenotypic switching, senescence, calcification and neointimal hyperplasia. Evidence of extracellular signaling of VSMCs and other cells via exosomal and circulating miRNAs was also presented. Lastly, current drawbacks and limitations of miRNA studies in CVD research and potential ways to overcome these disadvantages were discussed in detail. In-depth understanding of VSMC regulation via miRNAs will add substantial knowledge and advance research in diagnosis, disease progression and/or miRNA-derived therapeutic approaches in CVD research.


1998 ◽  
Vol 111 (11) ◽  
pp. 1535-1544 ◽  
Author(s):  
W. Xu ◽  
J.L. Coll ◽  
E.D. Adamson

Vinculin plays a role in signaling between integrins and the actin cytoskeleton. We reported earlier that F9-derived cells lacking vinculin are less spread, less adhesive, and move two times faster than wild-type F9 cells. Expression of intact vinculin in null cells restored all wild-type characteristics. In contrast, expression of the head (90 kDa) fragment exaggerated mutant characteristics, especially locomotion, which was double that of vinculin null cells. Expression of the tail domain also had a marked effect on locomotion in the opposite direction, reducing it to very low levels. The expression of the head plus tail domains together (no covalent attachment) effected a partial rescue towards wild-type phenotype, thus indicating that reexpressed polypeptides may be in their correct location and are interacting normally. Therefore, we conclude that: (1) the head domain is part of the locomotory force of the cell, modulated by the tail, and driven by the integrin/matrix connection; (2) intact vinculin is required for normal regulation of cell behavior, suggesting that vinculin head-tail interactions control cell adhesion, spreading, lamellipodia formation and locomotion.


1999 ◽  
Vol 181 (17) ◽  
pp. 5419-5425 ◽  
Author(s):  
N. Jamie Ryding ◽  
Maureen J. Bibb ◽  
Virginie Molle ◽  
Kim C. Findlay ◽  
Keith F. Chater ◽  
...  

ABSTRACT Sporulation mutants of Streptomyces coelicolor appear white because they are defective in the synthesis of the grey polyketide spore pigment, and such white (whi) mutants had been used to define eight sporulation loci, whiA,whiB, whiD, whiE, whiG,whiH, whiI, and whiJ (K. F. Chater, J. Gen. Microbiol. 72:9–28, 1972; N. J. Ryding, Ph.D. thesis, University of East Anglia, 1995). In an attempt to identify new whi loci, we mutagenized S. coelicolor M145 spores with nitrosoguanidine and identified 770 mutants with colonies ranging from white to medium grey. After excluding unstable strains, we examined the isolates by phase-contrast microscopy and chose 115 whi mutants with clear morphological phenotypes for further study. To exclude mutants representing cloned whi genes, self-transmissible SCP2*-derived plasmids carrying whiA, whiB,whiG, whiH, or whiJ (but notwhiD, whiE, or whiI) were introduced into each mutant by conjugation, and strains in which the wild-type phenotype was restored either partially or completely by any of these plasmids were excluded from further analysis. In an attempt to complement some of the remaining 31 whi mutants, an SCP2* library of wild-type S. coelicolor chromosomal DNA was introduced into 19 of the mutants by conjugation. Clones restoring the wild-type phenotype to 12 of the 19 strains were isolated and found to represent five distinct loci, designated whiK,whiL, whiM, whiN, andwhiO. Each of the five loci was located on the ordered cosmid library: whiL, whiM, whiN, and whiO occupied positions distinct from previously clonedwhi genes; whiK was located on the same cosmid overlap as whiD, but the two loci were shown by complementation to be distinct. The phenotypes resulting from mutations at each of these new loci are described.


2018 ◽  
Vol 9 (6) ◽  
pp. 615-631 ◽  
Author(s):  
B. Siddeek ◽  
C. Mauduit ◽  
C. Yzydorczyk ◽  
M. Benahmed ◽  
U. Simeoni

AbstractEpidemiological and experimental observations tend to prove that environment, lifestyle or nutritional challenges influence heart functions together with genetic factors. Furthermore, when occurring during sensitive windows of heart development, these environmental challenges can induce an ‘altered programming’ of heart development and shape the future heart disease risk. In the etiology of heart diseases driven by environmental challenges, epigenetics has been highlighted as an underlying mechanism, constituting a bridge between environment and heart health. In particular, micro-RNAs which are involved in each step of heart development and functions seem to play a crucial role in the unfavorable programming of heart diseases. This review describes the latest advances in micro-RNA research in heart diseases driven by early exposure to challenges and discusses the use of micro-RNAs as potential targets in the reversal of the pathophysiology.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Rihab E Hamed-Berair ◽  
Srinivas D Sithu ◽  
Nalinie Wickramasinghe ◽  
Jasmit Shah ◽  
Abhinav Agawral ◽  
...  

Micro RNAs (miR) are short non-coding RNAs that regulate several genes under pathophysiological conditions. Accumulating evidence suggest the involvement of miR in atherogenesis. However, limited information is available about atherogenic miR and the underling mechanisms by which miR affect atherogenesis. Our data shows that 12 weeks of western diet (WD) in LDL receptor-knockout (LDLR-KO) mice upregulated 99 and downregulated 50 miR in the aorta. Among the 41 differentially expressed miR associated with macrophage inflammation and apoptosis, expression of micro RNA-21 (miR-21) was increased by 1.4-fold (P<0.05). WD also increased the expression of miR-21 by 1.5-fold in bone marrow derived macrophages (BMDM). In vitro , LDL, oxidized LDL, acetylated LDL and LPS induced miR-21 by 2-3-fold (P<0.05) and down regulated its target protein PDCD4 in BMDM. Basally, miR-21 deficient BMDM showed increased secretion of IL-6, IL-9 and CXCL-2,-3,-4, and -10 (P<0.05)); and increased early and late apoptosis (2-3-fold, P<0.05). We also observed 40% decrease in the survival of F4/80+ cells during differentiation of bone marrow derived cells isolated from miR-21-KO mice. Stimulation of miR-21-KO BMDM with LPS significantly increased the activation of NF-κB and enhanced the secretion of several pro-inflammatory cytokines including TNFα, IL-6, IL-12 and CXCL-2 (2-10 fold; P<0.05); interferon gamma+LPS polarized the macrophages to pro-inflammatory M1 phenotype (increased expression of CD11c and CD86). Staurosporin and oxidized lipids derived aldehyde 4-hydroxynonenal significantly increased both early and late apoptosis of miR-21-KO BMDM (2-4-fold, P<0.05). This was accompanied by increased cleavage of caspase -3, -7 and -9. Transplantation of bone marrow cells from miR-21-KO into LDLR-KO mice, followed by 12 weeks of WD increased the lesion formation (1.7-fold, P<0.05), apoptosis (3-fold, P<0.05) and necrosis (1.6-fold, P<0.05) in the aortic valve of the chimeric mice. Collectively, these data suggest that miR-21 prevents atherosclerosis, at least in parts, by preventing macrophage apoptosis and inflammation.


Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Kumar Vaibhav ◽  
Shannon Williams ◽  
Sumbul Fatima ◽  
Babak Baban ◽  
Krishnan M Dhandapani ◽  
...  

Background: Micro RNAs (miRNAs) could target multiple mRNAs, repressing the protein translation. We report acute changes in humoral miRNAome in a murine thromboembolic stroke model (eMCAo), and demonstrate the benefits of miRNA therapy in improving cerebral blood flow (CBF). Methods: Non-biased micro RNA (miRNA) array and bioinformatics analysis was performed in plasma collected at 4h post-eMCAo from male mice (C57/B6, 16-weeks). Individual PCR for miRNAs was also performed in brain tissues at 24h post-eMCAo. Moreover, frozen human plasma samples collected at ~4.5h post-stroke were also used for miRNA analysis. Finally, the miRNA mimic that was predicted to target genes of our interest was also tested in vivo and in vitro . Results: Principal component analysis (PCA) of the miRNA-array showed ~68% variance in the humoral miRNAome 4h after eMCAo in mice, and a significant change in Stroke vs. Sham groups (Cut off value >2 fold; p<0.05). Of interest, the hairpin precursor of miR-449b was downregulated (~2.35 fold, p<0.05) at 4h post-eMCAo, while the mature miR-449b was also significantly reduced at 24h post-eMCAo. Mature miR-449b was significantly reduced in human stroke plasma, too. In human brain endothelial cells, miR-449b mimic downregulated gene expressions of both plasminogen activator inhibitor (PAI-1) and alpha 2- antiplasmin (α-AP) only in hypoxia but not during normoxia. Therefore, we finally tested the cholesterol-conjugated miR-449b mimic in the murine eMCAo model. Pre-treatment with miR-449b mimic (8 mg/kg bwt) increased the absolute CBF and reduced edema (as determined by MRI), and also improved the neurological outcomes and reduced % infarct volume (p<0.05). Results: The miR-449b mimic could be a possible therapy to suppress aberrant gene expressions of PAI-1 and α-AP, which will allow more spontaneous reperfusion and benefits from low dose tPA.


Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Rihab E Hamed-Berair ◽  
Abhinav Agarwal ◽  
Marcin Wysoczynski ◽  
Srinivas D Sithu ◽  
Nalinie S Wickramasinghe ◽  
...  

Micro RNA-21 (miR-21), an evolutionary conserved micro RNA has been implicated in the pathogenesis of restenosis, myocardial infarction and heart failure. However, little is known about the role of miR-21 in atherosclerosis. Our data show that in vitro, LDL, oxidized LDL, acetylated LDL and LPS induced miR-21 by 2-3-fold (P<0.05) and down regulated its target protein PDCD4 in bone marrow derived macrophages (BMDM). Feeding the LDL receptor-knockout (LDLR-KO) mice with western diet (WD, 8-20 weeks) increased the abundance of miR-21 in BMDM by 1.5-fold (P<0.05). Basally, BMDM isolated from miR-21-KO mice showed induction of TNF alpha, interferon gamma, M-CSF, RANTES, IP10 and LIF by (1.5-3.0-fold); increased early and late apoptosis (2-3-fold, P<0.05); and induced PDCD4 and PTEN. We also observed 40% decrease in the survival of F4/80+ cells during differentiation of bone marrow derived cells isolated from miR-21-KO mice. Stimulation of miR-21-KO BMDM with interferon gamma+LPS polarized the macrophages to pro-inflammatory M1 phenotype (increased expression of CD11c and CD86) and decreased IL-10 formation as compared with WT BMDM. Staurosporin and oxidized lipids derived aldehyde 4-hydroxynonenal significantly increased both early and late apoptosis of miR-21-KO BMDM (2-4-fold, P<0.05). This was accompanied by increased cleavage of caspase 3. Characterization of miR-21-KO mice showed 30% decrease in white blood cells and neutrophils in KO mice. However, levels of circulating immune cells and common progenitor cells in bone marrow of miR-21-KO mice were comparable with wild type mice. Transplantation of bone marrow cells from miR-21-KO into LDLR-KO mice, followed by 12 weeks of WD increased the lesion formation (1.7-fold, P<0.05), apoptosis (3-fold, P<0.05) and necrosis (1.6-fold, P<0.05) in the aortic valve of the chimeric mice. This was accompanied by increased accumulation of macrophages in the non-necrotic areas of the lesion and decrease in lesional smooth muscle cells. Plasma cholesterol levels, and lesional collagen and T-cell levels in the miR-21 chimeric mice were comparable with wild type chimeric mice. Collectively, these data suggest that miR-21 prevents atherosclerosis by inhibiting macrophage apoptosis, necrosis and inflammation.


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