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D’Agostino Y, Frigato E, Noviello TM, Toni M, Frabetti F, Cigliano L, Ceccarelli M, Sordino P, Cerulo L, Bertolucci C, D’Aniello S. Loss of circadian rhythmicity in bdnf knockout zebrafish larvae. iScience 2022; 25:104054. [PMID: 35345456 PMCID: PMC8957028 DOI: 10.1016/j.isci.2022.104054] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 01/14/2022] [Accepted: 03/08/2022] [Indexed: 12/13/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) plays a pivotal role in neuronal growth and differentiation, neuronal plasticity, learning, and memory. Using CRISPR/Cas9 technology, we generated a vital Bdnf null mutant line in zebrafish and carried out its molecular and behavioral characterization. Although no defects are evident on a morphological inspection, 66% of coding genes and 37% of microRNAs turned out to be differentially expressed in bdnf−/− compared with wild type sibling embryos. We deeply investigated the circadian clock pathway and confirmed changes in the rhythmic expression of clock (arntl1a, clock1a and clock2) and clock-controlled (aanat2) genes. The modulatory role of Bdnf on the zebrafish circadian clock was then validated by behavioral tests highlighting the absence of circadian activity rhythms in bdnf−/− larvae. The circadian behavior was partially rescued by pharmacological treatment. The bdnf−/− zebrafish line presented here is the first valuable and stable vertebrate model for the study of BDNF-related neurodevelopmental diseases Generation of a viable bdnf KO line in zebrafish Bdnf deficiency affects locomotor activity and thigmotaxis in larvae Differential RNA-seq analysis shows changes in expression of circadian clock genes Bdnf mutant fails in the generation of the behavioral circadian rhythmicity
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2
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Gu XY, Jin B, Qi ZD, Yin XF. MicroRNA is a potential target for therapies to improve the physiological function of skeletal muscle after trauma. Neural Regen Res 2021; 17:1617-1622. [PMID: 34916449 PMCID: PMC8771090 DOI: 10.4103/1673-5374.330620] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
MicroRNAs can regulate the function of ion channels in many organs. Based on our previous study we propose that miR-142a-39, which is highly expressed in denervated skeletal muscle, might affect cell excitability through similar mechanisms. In this study, we overexpressed or knocked down miR-142a-3p in C2C12 cells using a lentivirus method. After 7 days of differentiation culture, whole-cell currents were recorded. The results showed that overexpression of miR-142a-3p reduced the cell membrane capacitance, increased potassium current density and decreased calcium current density. Knockdown of miR-142a-3p reduced sodium ion channel current density. The results showed that change in miR-142a-3p expression affected the ion channel currents in C2C12 cells, suggesting its possible roles in muscle cell electrophysiology. This study was approved by the Animal Ethics Committee of Peking University in July 2020 (approval No. LA2017128).
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Affiliation(s)
- Xin-Yi Gu
- Department of Orthopedics and Traumatology, Peking University People's Hospital; Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, China
| | - Bo Jin
- Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, Jiangsu Province, China
| | - Zhi-Dan Qi
- Department of Orthopedics and Traumatology, Peking University People's Hospital; Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, China
| | - Xiao-Feng Yin
- Department of Orthopedics and Traumatology, Peking University People's Hospital; Key Laboratory of Trauma and Neural Regeneration (Peking University), Beijing, China
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3
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Anna G, Kannan NN. Post-transcriptional modulators and mediators of the circadian clock. Chronobiol Int 2021; 38:1244-1261. [PMID: 34056966 PMCID: PMC7611477 DOI: 10.1080/07420528.2021.1928159] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/26/2021] [Accepted: 05/03/2021] [Indexed: 01/04/2023]
Abstract
The endogenous circadian timekeeping system drives ~24-h rhythms in gene expression and rhythmically coordinates the physiology, metabolism and behavior in a wide range of organisms. Regulation at various levels is important for the accurate functioning of this circadian timing system. The core circadian oscillator consists of an interlocked transcriptional-translational negative feedback loop (TTFL) that imposes a substantial delay between the accumulation of clock gene mRNA and its protein to generate 24-h oscillations. This TTFL mediated daily oscillation of clock proteins is further fine-tuned by post-translational modifications that regulate the clock protein stability, interaction with other proteins and subcellular localization. Emerging evidence from various studies indicates that besides TTFL and post-translational modifications, post-transcriptional regulation plays a key role in shaping the rhythmicity of mRNAs and to delay the accumulation of clock proteins in relation to their mRNAs. In this review, we summarize the current knowledge on the importance of post-transcriptional regulatory mechanisms such as splicing, polyadenylation, the role of RNA-binding proteins, RNA methylation and microRNAs in the context of shaping the circadian rhythmicity in Drosophila and mammals. In particular, we discuss microRNAs, an important player in post-transcriptional regulation of core-clock machinery, circadian neural circuit, clock input, and output pathways. Furthermore, we provide an overview of the microRNAs that exhibit diurnal rhythm in expression and their role in mediating rhythmic physiological processes.
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Affiliation(s)
- Geo Anna
- Chronobiology Laboratory, School of Biology, Indian Institute of Science Education and Research (IISER), Thiruvananthapuram, Kerala 695551, India
| | - Nisha N Kannan
- Chronobiology Laboratory, School of Biology, Indian Institute of Science Education and Research (IISER), Thiruvananthapuram, Kerala 695551, India
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4
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Ray I, Goswami S. Circadian rhythm genes in cancer: insight into their functions and regulation involving noncoding RNAs. Chronobiol Int 2021; 38:1231-1243. [PMID: 34024245 DOI: 10.1080/07420528.2021.1928157] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The 24-h circadian rhythm handles a wide variety of physiological needs. Clock genes, in coordination with other tissue-specific factors regulate various processes and often turns responsible for the pathological conditions when altered. Cancer is one such disease where the clock genes have been shown to contribute at multiple levels modulating key hallmarks of cancer. Most importantly, adding to this complication, noncoding RNAs (ncRNAs) have emerged as one of the major post-transcriptional regulators of gene expression and many recent studies have indicated about involvement of microRNAs or long noncoding RNAs in the process. In this review, we have described how do circadian pathway genes participated in oncogenesis and also updated the latest status of ncRNA involvement. We also try to address the existing gaps to have a more comprehensive understanding of the phenomenon in future.Abbreviations: HIFs: hypoxia-inducible factors; VEGF: Vascular endothelial growth factor; Mdm2: Mouse double minute 2 homolog; ATM: Ataxia telangiectasia mutated; Chk2: Checkpoint kinase 2; Bcl-Xl: B-cell lymphoma-extra-large; Bcl-2: B-cell lymphoma 2; DGCR8: DiGeorge syndrome chromosomal region 8; PPAR-γ: Peroxisome proliferator-activated receptor gamma.
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Affiliation(s)
- Indrani Ray
- National Institute of Biomedical Genomics, Kalyani, India
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5
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Cavieres-Lepe J, Ewer J. Reciprocal Relationship Between Calcium Signaling and Circadian Clocks: Implications for Calcium Homeostasis, Clock Function, and Therapeutics. Front Mol Neurosci 2021; 14:666673. [PMID: 34045944 PMCID: PMC8144308 DOI: 10.3389/fnmol.2021.666673] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 04/09/2021] [Indexed: 12/03/2022] Open
Abstract
In animals, circadian clocks impose a daily rhythmicity to many behaviors and physiological processes. At the molecular level, circadian rhythms are driven by intracellular transcriptional/translational feedback loops (TTFL). Interestingly, emerging evidence indicates that they can also be modulated by multiple signaling pathways. Among these, Ca2+ signaling plays a key role in regulating the molecular rhythms of clock genes and of the resulting circadian behavior. In addition, the application of in vivo imaging approaches has revealed that Ca2+ is fundamental to the synchronization of the neuronal networks that make up circadian pacemakers. Conversely, the activity of circadian clocks may influence Ca2+ signaling. For instance, several genes that encode Ca2+ channels and Ca2+-binding proteins display a rhythmic expression, and a disruption of this cycling affects circadian function, underscoring their reciprocal relationship. Here, we review recent advances in our understanding of how Ca2+ signaling both modulates and is modulated by circadian clocks, focusing on the regulatory mechanisms described in Drosophila and mice. In particular, we examine findings related to the oscillations in intracellular Ca2+ levels in circadian pacemakers and how they are regulated by canonical clock genes, neuropeptides, and light stimuli. In addition, we discuss how Ca2+ rhythms and their associated signaling pathways modulate clock gene expression at the transcriptional and post-translational levels. We also review evidence based on transcriptomic analyzes that suggests that mammalian Ca2+ channels and transporters (e.g., ryanodine receptor, ip3r, serca, L- and T-type Ca2+ channels) as well as Ca2+-binding proteins (e.g., camk, cask, and calcineurin) show rhythmic expression in the central brain clock and in peripheral tissues such as the heart and skeletal muscles. Finally, we discuss how the discovery that Ca2+ signaling is regulated by the circadian clock could influence the efficacy of pharmacotherapy and the outcomes of clinical interventions.
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Affiliation(s)
- Javier Cavieres-Lepe
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile.,Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - John Ewer
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile
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6
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Ko GYP. Circadian regulation in the retina: From molecules to network. Eur J Neurosci 2020; 51:194-216. [PMID: 30270466 PMCID: PMC6441387 DOI: 10.1111/ejn.14185] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/16/2018] [Accepted: 08/20/2018] [Indexed: 12/14/2022]
Abstract
The mammalian retina is the most unique tissue among those that display robust circadian/diurnal oscillations. The retina is not only a light sensing tissue that relays light information to the brain, it has its own circadian "system" independent from any influence from other circadian oscillators. While all retinal cells and retinal pigment epithelium (RPE) possess circadian oscillators, these oscillators integrate by means of neural synapses, electrical coupling (gap junctions), and released neurochemicals (such as dopamine, melatonin, adenosine, and ATP), so the whole retina functions as an integrated circadian system. Dysregulation of retinal clocks not only causes retinal or ocular diseases, it also impacts the circadian rhythm of the whole body, as the light information transmitted from the retina entrains the brain clock that governs the body circadian rhythms. In this review, how circadian oscillations in various retinal cells are integrated, and how retinal diseases affect daily rhythms.
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Affiliation(s)
- Gladys Y-P Ko
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, Texas
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7
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Chen L, Zhang B, Yang L, Bai YG, Song JB, Ge YL, Ma HZ, Cheng JH, Ma J, Xie MJ. BMAL1 Disrupted Intrinsic Diurnal Oscillation in Rat Cerebrovascular Contractility of Simulated Microgravity Rats by Altering Circadian Regulation of miR-103/Ca V1.2 Signal Pathway. Int J Mol Sci 2019; 20:ijms20163947. [PMID: 31416128 PMCID: PMC6720455 DOI: 10.3390/ijms20163947] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/17/2019] [Accepted: 08/06/2019] [Indexed: 12/11/2022] Open
Abstract
The functional and structural adaptations in cerebral arteries could be one of the fundamental causes in the occurrence of orthostatic intolerance after space flight. In addition, emerging studies have found that many cardiovascular functions exhibit circadian rhythm. Several lines of evidence suggest that space flight might increase an astronaut’s cardiovascular risks by disrupting circadian rhythm. However, it remains unknown whether microgravity disrupts the diurnal variation in vascular contractility and whether microgravity impacts on circadian clock system. Sprague-Dawley rats were subjected to 28-day hindlimb-unweighting to simulate the effects of microgravity on vasculature. Cerebrovascular contractility was estimated by investigating vasoconstrictor responsiveness and myogenic tone. The circadian regulation of CaV1.2 channel was determined by recording whole-cell currents, evaluating protein and mRNA expressions. Then the candidate miRNA in relation with Ca2+ signal was screened. Lastly, the underlying pathway involved in circadian regulation of cerebrovascular contractility was determined. The major findings of this study are: (1) The clock gene BMAL1 could induce the expression of miR-103, and in turn modulate the circadian regulation of CaV1.2 channel in rat cerebral arteries at post-transcriptional level; and (2) simulated microgravity disrupted intrinsic diurnal oscillation in rat cerebrovascular contractility by altering circadian regulation of BMAL1/miR-103/CaV1.2 signal pathway.
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Affiliation(s)
- Li Chen
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Bin Zhang
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Lu Yang
- Department of Physiology, Fourth Military Medical University, Xi'an 710032, China
| | - Yun-Gang Bai
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Ji-Bo Song
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Yi-Ling Ge
- First Cadet Brigade, Fourth Military Medical University, Xi'an 710032, China
| | - Hong-Zhe Ma
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Jiu-Hua Cheng
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Jin Ma
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China
| | - Man-Jiang Xie
- Department of Aerospace Physiology, Key Laboratory of Aerospace Medicine of Ministry of Education, Fourth Military Medical University, Xi'an 710032, China.
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8
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Abstract
The small RNA regulatory molecules called microRNAs (miRNAs) play key roles in the development of most organisms. The expression of many different miRNAs has been described in the developing and mature vertebrate retina. The ability of miRNAs to regulate a diversity of messenger RNA targets allows them to have effects on many different developmental processes, but the functions of only a few miRNAs have been documented to date. Developmental transitions between cell states appear to be particularly sensitive to miRNA loss of function, as evidenced by specific miRNA knockdowns or from global perturbations in miRNA levels (e.g., Dicer deletion). However, we are still in only the very early stages of understanding the range of cellular functions miRNAs control during development.
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Affiliation(s)
- Thomas A Reh
- Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA;
| | - Robert Hindges
- Centre for Developmental Neurobiology, MRC Centre for Neurodevelopmental Disorders, King's College London, London SE1 1UL, United Kingdom;
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9
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Wang H, Liu L, Liu X, Zhang M, Li X. Correlation between miRNAs and target genes in response to Campylobacter jejuni inoculation in chicken. Poult Sci 2018; 97:485-493. [DOI: 10.3382/ps/pex343] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/14/2017] [Indexed: 12/19/2022] Open
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10
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Daily variations in the expression of miR-16 and miR-181a in human leukocytes. Blood Cells Mol Dis 2015; 54:364-8. [DOI: 10.1016/j.bcmd.2015.01.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/11/2015] [Indexed: 12/18/2022]
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11
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Kang Y, Jia P, Zhao H, Hu C, Yang X. MicroRNA-26a overexpression protects RGC-5 cells against H2O2-induced apoptosis. Biochem Biophys Res Commun 2015; 460:164-9. [PMID: 25757910 DOI: 10.1016/j.bbrc.2015.02.164] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 02/12/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND We intended to examine the functional role of microRNA 26 (miR-26a) in regulating H2O2-induced cytotoxicity and apoptosis in RGC-5 cells in vitro. METHOD Various concentrations of H2O2 (0-1000 μM) were added in RGC-5 culture. Cell cytotoxicity was monitored by viability assay and gene expression level of miR-26a examined by qRT-PCR. MicroRNA-26a mimic was then applied in the RGC-5 culture to examine its effect on upregulating endogenous miR-26a and rescuing H2O2-induced cytotoxicity. TUNEL immunostaining assay was used to further assess the protective effect of upregulating miR-26a on H2O2-induced apoptosis in RGC-5 cells. Direct targeting of miR-26a on Phosphatase and tensin homolog (PTEN) signaling pathway was assessed by luciferase assay and western blotting. PTEN was then ectopically over-expressed in RGC-5. And its effects on miR-26a mediated apoptosis protection in RGC-5 were investigated by western blot and TUNEL assay. RESULTS H2O2 induced cytotoxicity and down-regulated miR-26a in dose-dependent manner in RGC-5 cells. MiR-26a-mimic upregulated endogenous miR-26a gene levels, and then reduced H2O2-induced cytotoxicity, as well as H2O2-induced apoptosis in RGC-5 cells. PTEN was directly targeted by miR-26a. PTEN protein was upregulated, and phosphorylated AKT protein down-regulated while miR-26a was upregulated to reduce H2O2-induced apoptosis. Finally, overexpressing PTEN reversed the protective effect of miR-26a upregulation on RGC-5 apoptosis. CONCLUSION Upregulating miR-26a protects RGC-5 cell against cytotoxicity and apoptosis, probably through down-regulation of PTEN.
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Affiliation(s)
- Ye Kang
- Department of Ophthalmology, Yantaishan Hospital, 91 Jiefang Road, Yantai, 264000, Shandong, China
| | - Ping Jia
- Department of Ophthalmology, Yantai Development Area Hospital, Yantai, 264006, Shandong, China
| | - Huaqi Zhao
- Department of Ophthalmology, People's Hospital of Cao County, Heze, 274400, Shandong, China
| | - Chunyan Hu
- Department of Ophthalmology, People's Hospital of Cao County, Heze, 274400, Shandong, China
| | - Xiangze Yang
- Department of Ophthalmology, Weihai Municipal Hospital, 70 Heping Road, Weihai, 264200, Shandong, China.
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12
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Abstract
Ion channels and transporters are expressed in every living cell, where they participate in controlling a plethora of biological processes and physiological functions, such as excitation of cells in response to stimulation, electrical activities of cells, excitation-contraction coupling, cellular osmolarity, and even cell growth and death. Alterations of ion channels/transporters can have profound impacts on the cellular physiology associated with these proteins. Expression of ion channels/transporters is tightly regulated and expression deregulation can trigger abnormal processes, leading to pathogenesis, the channelopathies. While transcription factors play a critical role in controlling the transcriptome of ion channels/transporters at the transcriptional level by acting on the 5'-flanking region of the genes, microribonucleic acids (miRNAs), a newly discovered class of regulators in the gene network, are also crucial for expression regulation at the posttranscriptional level through binding to the 3'untranslated region of the genes. These small noncoding RNAs fine tune expression of genes involved in a wide variety of cellular processes. Recent studies revealed the role of miRNAs in regulating expression of ion channels/transporters and the associated physiological functions. miRNAs can target ion channel genes to alter cardiac excitability (conduction, repolarization, and automaticity) and affect arrhythmogenic potential of heart. They can modulate circadian rhythm, pain threshold, neuroadaptation to alcohol, brain edema, etc., through targeting ion channel genes in the neuronal systems. miRNAs can also control cell growth and tumorigenesis by acting on the relevant ion channel genes. Future studies are expected to rapidly increase to unravel a new repertoire of ion channels/transporters for miRNA regulation.
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Affiliation(s)
- Zhiguo Wang
- Harbin Medical University, Harbin, Heilongjiang, People's Republic of China.
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13
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Knoflach D, Kerov V, Sartori SB, Obermair GJ, Schmuckermair C, Liu X, Sothilingam V, Garrido MG, Baker SA, Glösmann M, Schicker K, Seeliger M, Lee A, Koschak A. Cav1.4 IT mouse as model for vision impairment in human congenital stationary night blindness type 2. Channels (Austin) 2013; 7:503-13. [PMID: 24051672 PMCID: PMC4042485 DOI: 10.4161/chan.26368] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 09/03/2013] [Indexed: 11/27/2022] Open
Abstract
Mutations in the CACNA1F gene encoding the Cav1.4 Ca (2+) channel are associated with X-linked congenital stationary night blindness type 2 (CSNB2). Despite the increasing knowledge about the functional behavior of mutated channels in heterologous systems, the pathophysiological mechanisms that result in vision impairment remain to be elucidated. This work provides a thorough functional characterization of the novel IT mouse line that harbors the gain-of-function mutation I745T reported in a New Zealand CSNB2 family. (1) Electroretinographic recordings in IT mice permitted a direct comparison with human data. Our data supported the hypothesis that a hyperpolarizing shift in the voltage-dependence of channel activation-as seen in the IT gain-of-function mutant (2)-may reduce the dynamic range of photoreceptor activity. Morphologically, the retinal outer nuclear layer in adult IT mutants was reduced in size and cone outer segments appeared shorter. The organization of the outer plexiform layer was disrupted, and synaptic structures of photoreceptors had a variable, partly immature, appearance. The associated visual deficiency was substantiated in behavioral paradigms. The IT mouse line serves as a specific model for the functional phenotype of human CSNB2 patients with gain-of-function mutations and may help to further understand the dysfunction in CSNB.
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Affiliation(s)
- Dagmar Knoflach
- Medical University Vienna; Centre for Physiology and Pharmacology; Department of Neurophysiology and Pharmacology; Vienna, Austria
| | - Vasily Kerov
- University of Iowa; Department of Molecular Physiology & Biophysics; Iowa City, IA USA
- University of Iowa; Department of Biochemistry; Iowa City, IA USA
| | - Simone B Sartori
- University of Innsbruck; Institute of Pharmacy, Pharmacology and Toxicology; Center for Chemistry and Biomedicine; Innsbruck, Austria
| | - Gerald J Obermair
- Medical University Innsbruck; Division of Physiology; Innsbruck, Austria
| | - Claudia Schmuckermair
- University of Innsbruck; Institute of Pharmacy, Pharmacology and Toxicology; Center for Chemistry and Biomedicine; Innsbruck, Austria
| | - Xiaoni Liu
- University of Iowa; Department of Molecular Physiology & Biophysics; Iowa City, IA USA
| | - Vithiyanjali Sothilingam
- University of Tübingen; Institute for Ophthalmic Research; Centre for Ophthalmology; Division of Ocular Neurodegeneration; Tübingen, Germany
| | - Marina Garcia Garrido
- University of Tübingen; Institute for Ophthalmic Research; Centre for Ophthalmology; Division of Ocular Neurodegeneration; Tübingen, Germany
| | - Sheila A Baker
- University of Iowa; Department of Biochemistry; Iowa City, IA USA
| | | | - Klaus Schicker
- Medical University Vienna; Centre for Physiology and Pharmacology; Department of Neurophysiology and Pharmacology; Vienna, Austria
| | - Mathias Seeliger
- University of Tübingen; Institute for Ophthalmic Research; Centre for Ophthalmology; Division of Ocular Neurodegeneration; Tübingen, Germany
| | - Amy Lee
- University of Iowa; Department of Molecular Physiology & Biophysics; Iowa City, IA USA
| | - Alexandra Koschak
- Medical University Vienna; Centre for Physiology and Pharmacology; Department of Neurophysiology and Pharmacology; Vienna, Austria
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14
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Ko ML, Shi L, Huang CCY, Grushin K, Park SY, Ko GYP. Circadian phase-dependent effect of nitric oxide on L-type voltage-gated calcium channels in avian cone photoreceptors. J Neurochem 2013; 127:314-28. [PMID: 23895452 DOI: 10.1111/jnc.12384] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 07/19/2013] [Accepted: 07/25/2013] [Indexed: 12/20/2022]
Abstract
Nitric oxide (NO) plays an important role in phase-shifting of circadian neuronal activities in the suprachiasmatic nucleus and circadian behavior activity rhythms. In the retina, NO production is increased in a light-dependent manner. While endogenous circadian oscillators in retinal photoreceptors regulate their physiological states, it is not clear whether NO also participates in the circadian regulation of photoreceptors. In this study, we demonstrate that NO is involved in the circadian phase-dependent regulation of L-type voltage-gated calcium channels (L-VGCCs). In chick cone photoreceptors, the L-VGCCα1 subunit expression and the maximal L-VGCC currents are higher at night, and both Ras-mitogen-activated protein kinase (MAPK)-extracellular signal-regulated kinase (Erk) and Ras-phosphatidylinositol 3 kinase (PI3K)-protein kinase B (Akt) are part of the circadian output pathways regulating L-VGCCs. The NO-cGMP-protein kinase G (PKG) pathway decreases L-VGCCα1 subunit expression and L-VGCC currents at night, but not during the day, and exogenous NO donor or cGMP decreases the phosphorylation of Erk and Akt at night. The protein expression of neural NO synthase (nNOS) is also under circadian control, with both nNOS and NO production being higher during the day. Taken together, NO/cGMP/PKG signaling is involved as part of the circadian output pathway to regulate L-VGCCs in cone photoreceptors. In cone photoreceptors, the protein expression of neural nitric oxide synthase (nNOS) and NO production are under circadian control. NO-cGMP-protein kinase G (PKG) signaling serves in the circadian output pathway to regulate the circadian rhythms of L-type voltage-gated calcium channels (L-VGCCs) in part through regulating the phosphorylation states of extracellular-signal-regulated kinase (Erk) and protein kinase B (Akt).
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Affiliation(s)
- Michael L Ko
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
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15
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Smythies J, Edelstein L. Interactions between the spike code and the epigenetic code during information processing in the brain. Front Mol Neurosci 2013; 6:17. [PMID: 23847467 PMCID: PMC3703540 DOI: 10.3389/fnmol.2013.00017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 06/18/2013] [Indexed: 12/03/2022] Open
Affiliation(s)
- John Smythies
- Department of Psychology, Center for Brain and Cognition, University of California San Diego La Jolla, CA, USA
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16
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Abstract
MicroRNAs (miRNAs) are a class of ~22 nucleotide-long small noncoding RNAs that target mRNAs for translational repression or degradation. miRNAs target mRNAs by base-pairing with the 3'-untranslated regions (3'-UTRs) of mRNAs. miRNAs are present in various species, from animals to plants. In this review, we summarize the identification, expression, and function of miRNAs in four important farm animal species: cattle, chicken, pig and sheep. In each of these species, hundreds of miRNAs have been identified through homology search, small RNA cloning and next generation sequencing. Real-time RT-PCR and microarray experiments reveal that many miRNAs are expressed in a tissue-specific or spatiotemporal-specific manner in farm animals. Limited functional studies suggest that miRNAs have important roles in muscle development and hypertrophy, adipose tissue growth, oocyte maturation and early embryonic development in farm animals. Increasing evidence suggests that single-nucleotide polymorphisms in miRNA target sites or miRNA gene promoters may contribute to variation in production or health traits in farm animals.
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Jia L, Wu J, Zhang L, Chen J, Zhong D, Xu S, Xie C, Cai J. Restoration of miR-1228* expression suppresses epithelial-mesenchymal transition in gastric cancer. PLoS One 2013; 8:e58637. [PMID: 23554909 PMCID: PMC3595239 DOI: 10.1371/journal.pone.0058637] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 02/05/2013] [Indexed: 12/13/2022] Open
Abstract
Dysregulated miRNAs play critical roles during carcinogenesis and cancer progression. In the present study, the function of miR-1228* in regulating cancer progression was investigated in gastric cancer. Decreased expression of miR-1228* was observed in human gastric cancer tissues comparing to normal tissues. Subsequently, the role of miR-1228* was evaluated in vivo using the tumor xenograft model. In this model, miR-1228* overexpression suppressed xenograft tumor formation. Furthermore, we demonstrated miR-1228* negatively regulated NF-κB activity in SGC-7901 gastric cancer cells and found that CK2A2 was a target of miR-1228*. Upregulation of miR-1228* decreased the expression of mesenchymal markers and increased the epithelial marker E-cadherin, suggesting its potential role in suppressing epithelial-mesenchymal transition. Collectively, these findings provide the first evidence that miR-1228* plays an important role in regulating gastric cancer growth and suggest that selective restoration of miR-1228* might be beneficial for gastric cancer therapy.
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Affiliation(s)
- Litao Jia
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
- Department of Gastroenterology, Tongde Hospital of Zhejiang Province, Hangzhou, China
| | - Jia Wu
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
| | - Lu Zhang
- Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Jiamin Chen
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
| | - Dandan Zhong
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
| | - Song Xu
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
| | - Chuangao Xie
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
| | - Jianting Cai
- Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, China
- * E-mail:
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Ragusa M, Caltabiano R, Russo A, Puzzo L, Avitabile T, Longo A, Toro MD, Di Pietro C, Purrello M, Reibaldi M. MicroRNAs in vitreus humor from patients with ocular diseases. Mol Vis 2013; 19:430-40. [PMID: 23441115 PMCID: PMC3580974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 02/18/2013] [Indexed: 11/02/2022] Open
Abstract
PURPOSE Based on evidence that microRNAs (miRNAs) are found in many biologic fluids (e.g., urine, saliva, pleural fluid), we sought to detect the presence of miRNAs and analyze their profile in vitreous humor (VH) from patients affected by various ocular diseases. METHODS MiRNAs were purified from VH samples taken during vitrectomy, by using the Qiagen miRNeasy Mini Kit. The expression profile on 745 miRNAs was performed by using TaqMan Low Density Array. Single TaqMan expression assays were performed on 18 VH samples (six each from patients with choroidal melanomas, retinal detachment, or macular hole) for miRNAs commonly expressed in serum or retinal cells: let-7b, miR-21, miR-26a, miR-146a, miR-199-3p, miR-210, miR-374a*, miR-532-5p. RNA extracted from serum of six healthy donors or from formalin-fixed, paraffin-embedded samples of choroidal melanocytes from four uveal melanomas (epithelioid cells) and from three unaffected eyes were used as controls. RESULTS We identified the presence of 94 circulating small RNAs in the vitreous, some of which (miR-9, miR-9*, miR-125a-3p, miR-184, miR-211, miR-214, miR-302c, miR-452, miR-628, miR-639) are particularly abundant in the VH but downrepresented or not detectable in serum. MiR-146a and miR-26a were overexpressed more than threefold in VH from patients with uveal melanomas compared to the other pathological groups (Wilcoxon signed-rank test, p value < 0.05). CONCLUSIONS Our experimental data suggest that a specific set of circulating miRNAs is secreted in the vitreous, which is quite different from the miRNA pattern in serum, and that the quantity of vitreal miRNAs could change, depending on the pathologies of the eye.
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Affiliation(s)
- Marco Ragusa
- Department Gian Filippo Ingrassia, Unità di BioMedicina Molecolare Genomica e dei Sistemi Complessi, Genetica, Biologia Computazionale, Università di Catania, Catania, Italy
| | - Rosario Caltabiano
- Department Gian Filippo Ingrassia, Unità di Anatomia Patologica, Università di Catania, Catania, Italy
| | - Andrea Russo
- Department of Ophthalmology, University of Catania, Catania, Italy
| | - Lidia Puzzo
- Department Gian Filippo Ingrassia, Unità di Anatomia Patologica, Università di Catania, Catania, Italy
| | | | - Antonio Longo
- Department of Ophthalmology, University of Catania, Catania, Italy
| | - Mario D. Toro
- Department of Ophthalmology, University of Catania, Catania, Italy
| | - Cinzia Di Pietro
- Department Gian Filippo Ingrassia, Unità di BioMedicina Molecolare Genomica e dei Sistemi Complessi, Genetica, Biologia Computazionale, Università di Catania, Catania, Italy
| | - Michele Purrello
- Department Gian Filippo Ingrassia, Unità di BioMedicina Molecolare Genomica e dei Sistemi Complessi, Genetica, Biologia Computazionale, Università di Catania, Catania, Italy
| | - Michele Reibaldi
- Department of Ophthalmology, University of Catania, Catania, Italy
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Abstract
Rhythmic mRNA expression is a hallmark of circadian biology and has been described in numerous experimental systems including mammals. A small number of core clock gene mRNAs and a much larger number of output mRNAs are under circadian control. The rhythmic expression of core clock genes is regulated at the transcriptional level, and this regulation is important for the timekeeping mechanism. However, the relative contribution of transcriptional and post transcriptional regulation to global circadian mRNA oscillations is unknown. To address this issue in Drosophila, we isolated nascent RNA from adult fly heads collected at different time points and subjected it to high-throughput sequencing. mRNA was isolated and sequence din parallel. Some genes had cycling nascent RNAs with no cycling mRNA, caused,most likely, by light-mediated read-through transcription. Most genes with cycling mRNAs had significant nascent RNA cycling amplitudes, indicating a prominent role for circadian transcriptional regulation. However, a considerable fraction had higher mRNA amplitudes than nascent RNA amplitudes. The same comparison for core clock gene mRNAs gives rise to a qualitatively similar conclusion. The data therefore indicate a significant quantitative contribution of post transcriptional regulation to mRNA cycling.
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20
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Majer A, Medina SJ, Niu Y, Abrenica B, Manguiat KJ, Frost KL, Philipson CS, Sorensen DL, Booth SA. Early mechanisms of pathobiology are revealed by transcriptional temporal dynamics in hippocampal CA1 neurons of prion infected mice. PLoS Pathog 2012; 8:e1003002. [PMID: 23144617 PMCID: PMC3493483 DOI: 10.1371/journal.ppat.1003002] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 09/13/2012] [Indexed: 12/23/2022] Open
Abstract
Prion diseases typically have long pre-clinical incubation periods during which time the infectious prion particle and infectivity steadily propagate in the brain. Abnormal neuritic sprouting and synaptic deficits are apparent during pre-clinical disease, however, gross neuronal loss is not detected until the onset of the clinical phase. The molecular events that accompany early neuronal damage and ultimately conclude with neuronal death remain obscure. In this study, we used laser capture microdissection to isolate hippocampal CA1 neurons and determined their pre-clinical transcriptional response during infection. We found that gene expression within these neurons is dynamic and characterized by distinct phases of activity. We found that a major cluster of genes is altered during pre-clinical disease after which expression either returns to basal levels, or alternatively undergoes a direct reversal during clinical disease. Strikingly, we show that this cluster contains a signature highly reminiscent of synaptic N-methyl-D-aspartic acid (NMDA) receptor signaling and the activation of neuroprotective pathways. Additionally, genes involved in neuronal projection and dendrite development were also altered throughout the disease, culminating in a general decline of gene expression for synaptic proteins. Similarly, deregulated miRNAs such as miR-132-3p, miR-124a-3p, miR-16-5p, miR-26a-5p, miR-29a-3p and miR-140-5p follow concomitant patterns of expression. This is the first in depth genomic study describing the pre-clinical response of hippocampal neurons to early prion replication. Our findings suggest that prion replication results in the persistent stimulation of a programmed response that is mediated, at least in part, by synaptic NMDA receptor activity that initially promotes cell survival and neurite remodelling. However, this response is terminated prior to the onset of clinical symptoms in the infected hippocampus, seemingly pointing to a critical juncture in the disease. Manipulation of these early neuroprotective pathways may redress the balance between degeneration and survival, providing a potential inroad for treatment. Neurodegenerative diseases affect an ever-increasing proportion of the population; therefore, there is an urgent need to develop treatments. Prion disorders belong to this group of diseases and although rare and uniquely transmissible, share many features on a sub-cellular level. Central to disease is progressive synaptic impairment that invariably leads to the irreversible loss of neurons. Understanding this process is undoubtedly essential for rational drug discovery. In this study we looked at neurons very early in disease, when prions are barely detectable and there are no clinical symptoms observed. Specifically, we performed a comprehensive analysis of transcriptional changes within a particularly dense area of neurons, the CA1 hippocampus region, from prion-infected and control mice. In this way we were able to enrich our data for molecular changes unique to neurons and minimize those changes characteristic of support cells such as astrocytes and microglia. We detected the activation of a transcriptional program indicative of a protective mechanism within these neurons early in disease. This mechanism diminished as disease progressed and was lost altogether, concurrently with the onset of clinical symptoms. These findings demonstrate the ability of neurons to mount an initial neuroprotective response to prions that could be exploited for therapy development.
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Affiliation(s)
- Anna Majer
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Sarah J. Medina
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Yulian Niu
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Bernard Abrenica
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Kathy J. Manguiat
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Kathy L. Frost
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Clark S. Philipson
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Debra L. Sorensen
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Stephanie A. Booth
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
- * E-mail:
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21
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The oscillating miRNA 959-964 cluster impacts Drosophila feeding time and other circadian outputs. Cell Metab 2012; 16:601-12. [PMID: 23122660 PMCID: PMC3534751 DOI: 10.1016/j.cmet.2012.10.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 06/07/2012] [Accepted: 10/08/2012] [Indexed: 11/22/2022]
Abstract
We sequenced Drosophila head RNA to identify a small set of miRNAs that undergo robust circadian cycling. We concentrated on a cluster of six miRNAs, mir-959-964, all of which peak at about ZT12 or lights off. The cluster pri-miRNA is transcribed under bona fide circadian transcriptional control, and all six mature miRNAs have short half-lives, a requirement for cycling. A viable Gal4 knockin strain localizes prominent cluster miRNA expression to the adult head fat body. Analysis of cluster knockout and overexpression strains indicates that innate immunity, metabolism, and feeding behavior are under cluster miRNA regulation. Manipulation of food intake also affects the levels and timing of cluster miRNA transcription with no more than minor effects on the core circadian oscillator. These observations indicate a feedback circuit between feeding time and cluster miRNA expression function as well as a surprising role of posttranscriptional regulation in the circadian control of these phenotypes.
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22
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Mehta N, Cheng HYM. Micro-managing the circadian clock: The role of microRNAs in biological timekeeping. J Mol Biol 2012; 425:3609-24. [PMID: 23142644 DOI: 10.1016/j.jmb.2012.10.022] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 10/16/2012] [Accepted: 10/31/2012] [Indexed: 12/11/2022]
Abstract
Evolved under the selective pressures of a 24-h world, circadian timekeeping mechanisms are present in virtually all living organisms to coordinate daily rhythms in physiology and behavior. Until recently, the circadian clock was modeled as simple, interlocked transcription-translation feedback loops driving rhythms in gene expression of a handful of core clock genes. However, it has become evident that circadian clock regulation is immensely more complex than once thought and involves posttranscriptional, translational and posttranslational mechanisms. In particular, there has been a growing awareness of the vital role played by microRNAs (miRNAs) in regulating various aspects of circadian clock function. In this review, we will summarize our current knowledge of miRNA-dependent regulation of the circadian timing system in multiple organisms, including flies, mammals and higher plants. We will also discuss future perspectives for research on the role of miRNAs and noncoding RNAs in circadian regulation of health and disease.
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Affiliation(s)
- Neel Mehta
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road North, Mississauga, ON, Canada L5L 1C6
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23
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Ion channels/transporters as epigenetic regulators? -a microRNA perspective. SCIENCE CHINA-LIFE SCIENCES 2012; 55:753-60. [PMID: 23015123 DOI: 10.1007/s11427-012-4369-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Accepted: 07/30/2012] [Indexed: 10/27/2022]
Abstract
MicroRNA (miRNA) alterations in response to changes in an extracellular microenvironment have been observed and considered as one of the major mechanisms for epigenetic modifications of the cell. While enormous efforts have been made in the understanding of the role of miRNAs in regulating cellular responses to the microenvironment, the mechanistic insight into how extracellular signals can be transduced into miRNA alterations in cells is still lacking. Interestingly, recent studies have shown that ion channels/transporters, which are known to conduct or transport ions across the cell membrane, also exhibit changes in levels of expression and activities in response to changes of extracellular microenvironment. More importantly, alterations in expression and function of ion channels/transporters have been shown to result in changes in miRNAs that are known to change in response to alteration of the microenvironment. In this review, we aim to summarize the recent data demonstrating the ability of ion channels/transporters to transduce extracellular signals into miRNA changes and propose a potential link between cells and their microenvironment through ion channels/transporters. At the same time, we hope to provide new insights into epigenetic regulatory mechanisms underlying a number of physiological and pathological processes, including embryo development and cancer metastasis.
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24
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The physiological impact of microRNA gene regulation in the retina. Cell Mol Life Sci 2012; 69:2739-50. [PMID: 22460583 DOI: 10.1007/s00018-012-0976-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 02/22/2012] [Accepted: 03/15/2012] [Indexed: 12/21/2022]
Abstract
microRNAs (miRNAs) are small, stable RNA molecules that post-transcriptionally regulate gene expression in plants and animals by base pairing to partially complementary sequences on target mRNAs to inhibit protein synthesis. More than 250 miRNAs are reportedly expressed in the retina, and miRNA gene regulation has been shown to affect retinal development, function, and disease. Here we highlight recent advances in understanding the functional roles of vertebrate retinal miRNAs. Details are emerging about the physiological impact of specific miRNAs in the developing and mature retina, and we discuss a group of emerging technologies for studying miRNAs, which can be employed to yield a deeper understanding of retinal miRNA gene regulation.
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25
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Luo W, Sehgal A. Regulation of circadian behavioral output via a MicroRNA-JAK/STAT circuit. Cell 2012; 148:765-79. [PMID: 22305007 DOI: 10.1016/j.cell.2011.12.024] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 10/28/2011] [Accepted: 12/15/2011] [Indexed: 10/14/2022]
Abstract
Although molecular components of the circadian clock are known, mechanisms that transmit signals from the clock and produce rhythmic behavior are poorly understood. We find that the microRNA miR-279 regulates the JAK/STAT pathway to drive rest:activity rhythms in Drosophila. Overexpression of microRNA miR-279 or miR-279 deletion attenuates rest:activity rhythms. Oscillations of the clock protein PERIOD are normal in pacemaker neurons lacking miR-279, suggesting that miR-279 acts downstream of the clock. We identify the JAK/STAT ligand, Upd, as a target of miR-279 and show that knockdown of Upd rescues the behavioral phenotype of miR-279 mutants. Manipulations of the JAK/STAT pathway also disrupt circadian rhythms. In addition, central clock neurons project in the vicinity of Upd-expressing neurons, providing a possible physical connection by which the central clock could regulate JAK/STAT signaling to control rest:activity rhythms.
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Affiliation(s)
- Wenyu Luo
- Cell and Molecular Biology Program, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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26
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Carrillo ED, Escobar Y, González G, Hernández A, Galindo JM, García MC, Sánchez JA. Posttranscriptional regulation of the β2-subunit of cardiac L-type Ca2+ channels by MicroRNAs during long-term exposure to isoproterenol in rats. J Cardiovasc Pharmacol 2011; 58:470-8. [PMID: 21753737 DOI: 10.1097/fjc.0b013e31822a789b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION AND METHODS The effects of long-term β-adrenergic administration on the expression levels of the cardiac L-type Ca channel β2 subunit, which regulates channel trafficking and function, were characterized in adult rats. RESULTS Systemic administration of isoproterenol (150 mg·kg·h) for 2 d led to a 50% increase in the ventricular wet weight-to-body weight ratio (mg/g) and of more than two-fold in the expression of actin protein. In contrast, β2 subunit protein levels decreased (down to 49%), while mRNA levels remained unchanged. Furthermore, levels of microRNAs (miRs), including miR-21 and miR-132, were upregulated (7.2 and 7.9 fold, respectively). Transfection of these miRs into HEK293 cells attenuated expression of a luciferase reporter gene controlled by a conserved 3'-untranslated region (UTR) of the β2 subunit (down to 67% and 56%, respectively). Systemic administration of isoproterenol also led to briefer intracellular Ca transients during action potentials measured in isolated cardiomyocytes (down to 65%). CONCLUSION These results suggest that cardiac L-type Ca channel β2 subunit protein expression may be downregulated by miRs in response to long-term activation of β-adrenergic signaling, possibly as an adaptive response in cardiac hypertrophy and sustained β-adrenergic states.
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Affiliation(s)
- Elba D Carrillo
- Departamento de Farmacología, Centro de Investigación y de Estudios Avanzados, del Instituto Politécnico Nacional, México, DF, México
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27
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Shende VR, Goldrick MM, Ramani S, Earnest DJ. Expression and rhythmic modulation of circulating microRNAs targeting the clock gene Bmal1 in mice. PLoS One 2011; 6:e22586. [PMID: 21799909 PMCID: PMC3142187 DOI: 10.1371/journal.pone.0022586] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 06/30/2011] [Indexed: 02/01/2023] Open
Abstract
MicroRNAs (miRNAs) interact with 3' untranslated region (UTR) elements of target genes to regulate mRNA stability or translation and thus play a role in regulating many different biological processes, including circadian rhythms. However, specific miRNAs mediating the regulation of essential clock genes remain largely unknown. Because vesicles containing membrane-bound miRNAs are present in the circulatory system, we examined miRNAs predicted to target the clock gene, Bmal1, for evidence of rhythmic fluctuations in circulating levels and modulatory effects on the 3' UTR activity of Bmal1. A number of miRNAs with Bmal1 as a predicted target were expressed in the serum of mice exposed to LD 12:12 and of these miRNAs, miR-152 and miR-494 but not miR-142-3p were marked by diurnal oscillations with bimodal peaks in expression occurring near the middle of the day and 8 or 12 hr later during the night. Co-transfection of pre-miR over-expression constructs for miR-494 and miR-142-3p in HEK293 cells had significant effects in repressing luciferase-reported Bmal1 3' UTR activity by as much as 60%, suggesting that these miRNAs may function as post-transcriptional modulators of Bmal1. In conjunction with previous studies implicating miRNAs as extracellular regulatory signals, our results suggest that circulating miRNAs may play a role in the regulation of the molecular clockworks in peripheral circadian oscillators.
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Affiliation(s)
- Vikram R. Shende
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Center for Biological Clocks Research, Texas A&M University, College Station, Texas, United States of America
| | | | | | - David J. Earnest
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Center for Biological Clocks Research, Texas A&M University, College Station, Texas, United States of America
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, College Station, Texas, United States of America
- * E-mail:
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28
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Zhang L, Weng W, Guo J. Posttranscriptional mechanisms in controlling eukaryotic circadian rhythms. FEBS Lett 2011; 585:1400-5. [PMID: 21414314 DOI: 10.1016/j.febslet.2011.03.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 03/08/2011] [Accepted: 03/09/2011] [Indexed: 10/18/2022]
Abstract
The circadian clock is essential in almost all living organisms to synchronise biochemical, metabolic, physiological and behavioural cycles to daily changing environmental factors. In a highly conserved fashion, the circadian clock is primarily controlled by multiple positive and negative molecular circuitries that control gene expression. More recently, research in Neurospora and other eukaryotes has uncovered the involvement of additional regulatory components that operate at the posttranslational level to fine tune the circadian system. Though it remains poorly understood, a growing body of evidence has shown that posttranscriptional regulation controls the expression of both circadian oscillator and output gene transcripts at a number of different steps. This regulation is crucial for driving and maintaining robust circadian rhythms. Here we review recent advances in circadian rhythm research at the RNA level.
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Affiliation(s)
- Lin Zhang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
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29
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Cao R, Anderson FE, Jung YJ, Dziema H, Obrietan K. Circadian regulation of mammalian target of rapamycin signaling in the mouse suprachiasmatic nucleus. Neuroscience 2011; 181:79-88. [PMID: 21382453 DOI: 10.1016/j.neuroscience.2011.03.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 02/27/2011] [Accepted: 03/01/2011] [Indexed: 12/19/2022]
Abstract
Circadian (24-h) rhythms influence virtually every aspect of mammalian physiology. The main rhythm generation center is located in the suprachiasmatic nucleus (SCN) of the hypothalamus, and work over the past several years has revealed that rhythmic gene transcription and post-translational processes are central to clock timing. In addition, rhythmic translation control has also been implicated in clock timing; however the precise cell signaling pathways that drive this process are not well known. Here we report that a key translation activation cascade, the mammalian target of rapamycin (mTOR) pathway, is under control of the circadian clock in the SCN. Using phosphorylated S6 ribosomal protein (pS6) as a marker of mTOR activity, we show that the mTOR cascade exhibits maximal activity during the subjective day, and minimal activity during the late subjective night. Importantly, expression of S6 was not altered as a function of circadian time. Rhythmic S6 phosphorylation was detected throughout the dorsoventral axis of the SCN, thus suggesting that rhythmic mTOR activity was not restricted to a subset of SCN neurons. Rather, rhythmic pS6 expression appeared to parallel the expression pattern of the clock gene period1 (per1). Using a transgenic per1 reporter gene mouse strain, we found a statistically significant cellular level correlation between pS6 and per1 gene expression over the circadian cycle. Further, photic stimulation triggered a coordinate upregulation of per1 and mTOR activation in a subset of SCN cells. Interestingly, this cellular level correlation between mTOR activity and per1 expression appears to be specific, since a similar expression profile for pS6 and per2 or c-FOS was not detected. Finally, we show that mTOR activity is downstream of the ERK/MAPK signal transduction pathway. Together these data reveal that mTOR pathway activity is under the control of the SCN clock, and suggests that mTOR signaling may contribute to distinct aspects of the molecular clock timing process.
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Affiliation(s)
- R Cao
- Department of Neuroscience, Ohio State University, Columbus, OH 43210, USA
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30
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Hansen KF, Sakamoto K, Obrietan K. MicroRNAs: a potential interface between the circadian clock and human health. Genome Med 2011; 3:10. [PMID: 21345247 PMCID: PMC3092095 DOI: 10.1186/gm224] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The biochemical activity of a stunning diversity of cell types and organ systems is shaped by a 24-hour (circadian) clock. This rhythmic drive to a good deal of the transcriptome (up to 15% of all coding genes) imparts circadian modulation over a wide range of physiological and behavioral processes (from cell division to cognition). Further, dysregulation of the clock has been implicated in the pathogenesis of a large and diverse array of disorders, such as hypertension, cancer and depression. Indeed, the possibility of utilizing therapeutic approaches that target clock physiology (that is, chronotherapy) has gained broad interest. However, a deeper understanding of the underlying molecular mechanisms that modulate the clock, and give rise to organ-specific clock transcriptomes, will be required to fully realize the power of chronotherapies. Recently, microRNAs have emerged as significant players in circadian clock timing, thus raising the possibility that clock-controlled microRNAs could contribute to disorders of the human circadian timing system. Here, we highlight recent work revealing a key role for microRNAs in clock physiology, and discuss potential approaches to unlocking their utility as effectors of circadian physiology and pathophysiology.
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Affiliation(s)
- Katelin F Hansen
- Department of Neuroscience, Ohio State University, Columbus, OH 43210, USA.
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31
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Guillon-Munos A, Dambrine G, Richerioux N, Coupeau D, Muylkens B, Rasschaert D. The chicken miR-150 targets the avian orthologue of the functional zebrafish MYB 3'UTR target site. BMC Mol Biol 2010; 11:67. [PMID: 20813039 PMCID: PMC2940766 DOI: 10.1186/1471-2199-11-67] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Accepted: 09/02/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The c-myb proto-oncogene is the founding member of a family of transcription factors involved principally in haematopoiesis, in diverse organisms, from zebrafish to mammals. Its deregulation has been implicated in human leukaemogenesis and other cancers. The expression of c-myb is tightly regulated by post-transcriptional mechanisms involving microRNAs. MicroRNAs are small, highly conserved non-coding RNAs that inhibit translation and decrease mRNA stability by binding to regulatory motifs mostly located in the 3'UTR of target mRNAs conserved throughout evolution. MYB is an evolutionarily conserved miR-150 target experimentally validated in mice, humans and zebrafish. However, the functional miR-150 sites of humans and mice are orthologous, whereas that of zebrafish is different. RESULTS We identified the avian mature miRNA-150-5P, Gallus gallus gga-miR-150 from chicken leukocyte small-RNA libraries and showed that, as expected, the gga-miR-150 sequence was highly conserved, including the seed region sequence present in the other miR-150 sequences listed in miRBase. Reporter assays showed that gga-miR-150 acted on the avian MYB 3'UTR and identified the avian MYB target site involved in gga-miR-150 binding. A comparative in silico analysis of the miR-150 target sites of MYB 3'UTRs from different species led to the identification of a single set of putative target sites in amphibians and zebrafish, whereas two sets of putative target sites were identified in chicken and mammals. However, only the target site present in the chicken MYB 3'UTR that was identical to that in zebrafish was functional, despite the additional presence of mammalian target sites in chicken. This specific miR-150 site usage was not cell-type specific and persisted when the chicken c-myb 3'UTR was used in the cell system to identify mammalian target sites, showing that this miR-150 target site usage was intrinsic to the chicken c-myb 3'UTR. CONCLUSION Our study of the avian MYB/gga-miR-150 interaction shows a conservation of miR-150 target site functionality between chicken and zebrafish that does not extend to mammals.
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Affiliation(s)
- Audrey Guillon-Munos
- Université François Rabelais, Equipe Transcription, Lymphome Viro-induit, UFR Sciences et Techniques, Parc de Grandmont, F-37200 Tours, France
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miR-204 is required for lens and retinal development via Meis2 targeting. Proc Natl Acad Sci U S A 2010; 107:15491-6. [PMID: 20713703 DOI: 10.1073/pnas.0914785107] [Citation(s) in RCA: 133] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
MicroRNAs (miRNAs) are small noncoding RNAs that have important roles in the regulation of gene expression. The roles of individual miRNAs in controlling vertebrate eye development remain, however, largely unexplored. Here, we show that a single miRNA, miR-204, regulates multiple aspects of eye development in the medaka fish (Oryzias latipes). Morpholino-mediated ablation of miR-204 expression resulted in an eye phenotype characterized by microphthalmia, abnormal lens formation, and altered dorsoventral (D-V) patterning of the retina, which is associated with optic fissure coloboma. Using a variety of in vivo and in vitro approaches, we identified the transcription factor Meis2 as one of the main targets of miR-204 function. We show that, together with altered regulation of the Pax6 pathway, the abnormally elevated levels of Meis2 resulting from miR-204 inactivation are largely responsible for the observed phenotype. These data provide an example of how a specific miRNA can regulate multiple events in eye formation; at the same time, they uncover an as yet unreported function of Meis2 in the specification of D-V patterning of the retina.
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Dicer is required for the transition from early to late progenitor state in the developing mouse retina. J Neurosci 2010; 30:4048-61. [PMID: 20237275 DOI: 10.1523/jneurosci.4982-09.2010] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
MicroRNAs (miRNAs), small 19-25 nucleotide RNAs that influence gene expression through posttranscriptional regulation of mRNA translation and degradation, have recently emerged as important regulators of neural development. Using conditional knock-out of Dicer, an RNase III enzyme required for miRNA maturation, previous studies have demonstrated an essential role for miRNAs in mouse cortical, inner ear, and olfactory development. However, a previous study (Damiani et al., 2008) using a Chx10cre mouse to delete Dicer in retinal progenitors reported no defects in the retina before the second postnatal week, suggesting that miRNAs are not required for mouse retinal development. In an effort to further study the role of miRNAs during retinal development and resolve this apparent conflict, we conditionally knocked out Dicer using a different (alphaPax6cre) line of transgenic mice. In contrast to the previous study, we demonstrate an essential role for miRNAs during mouse retinal development. In the absence of Dicer in the embryonic retina, production of early generated cell types (ganglion and horizontal cells) is increased, and markers of late progenitors are not expressed. This phenotype persists into postnatal retina, in which we find the Dicer-deficient progenitors fail to generate late-born cell types such as rods and Müller glia but continue to generate ganglion cells. We further characterize the dynamic expression of miRNAs during retinal progenitor differentiation and provide a comprehensive profile of miRNAs expressed during retinal development. We conclude that Dicer is necessary for the developmental change in competence of the retinal progenitor cells.
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Witwer KW, Sisk JM, Gama L, Clements JE. MicroRNA regulation of IFN-beta protein expression: rapid and sensitive modulation of the innate immune response. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2010; 184:2369-76. [PMID: 20130213 PMCID: PMC3076721 DOI: 10.4049/jimmunol.0902712] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
IFN-beta production is an inaugural event in the innate immune response to viral infections, with relatively small fold changes in IFN-beta expression resulting in the activation of important antiviral signaling cascades. In our rapid SIV/macaque model of HIV encephalitis, the virus enters the CNS within 4 d of infection, accompanied by a marked IFN-beta response that wanes as SIV replication is controlled. The centrality of IFN-beta to the innate antiviral response in the CNS combines with the potential inflammatory damage associated with long-term activation of this pathway to suggest that IFN-beta may be subject to regulatory fine-tuning in addition to well-established transcriptional and message stability mechanisms of regulation. In this paper, we present for the first time evidence that microRNAs (miRNAs), including miR-26a, -34a, -145, and let-7b, may directly regulate IFN-beta in human and macaque cells. In primary primate macrophages, the main cell type implicated in HIV and SIV infection in the CNS, specific miRNAs reduce, whereas miRNA inhibitors enhance, IFN-beta protein production. The potential biologic significance of this regulation is supported by evidence of an apparent negative feedback loop, with increased expression of three IFN-beta-regulating miRNAs by primate macrophages exposed to recombinant IFN-beta or stimulated to produce IFN-beta. Thus, miRNAs may contribute significantly to the regulation of IFN-beta in innate immune responses.
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Affiliation(s)
- Kenneth W. Witwer
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jeanne M. Sisk
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lucio Gama
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Janice E. Clements
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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