scholarly journals Transcriptional Regulation of lncRNA Genes by Histone Modification in Alzheimer’s Disease

2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Guoqiang Wan ◽  
Wenyang Zhou ◽  
Yang Hu ◽  
Rui Ma ◽  
Shuilin Jin ◽  
...  

Increasing studies have revealed that long noncoding RNAs (lncRNAs) are not transcriptional noise but play important roles in the regulation of a wide range of biological processes, and the dysregulation of lncRNA genes is associated with disease development. Alzheimer’s disease (AD) is a chronic neurodegenerative disease that usually starts slowly and gets worse over time. However, little is known about the roles of lncRNA genes in AD and how the lncRNA genes are transcriptionally regulated. Herein, we analyzed RNA-seq data and ChIP-seq histone modification data from CK-p25 AD model and control mice and identified 72 differentially expressed lncRNA genes, 4,917 differential peaks of H3K4me3, and 1,624 differential peaks of H3K27me3 between AD and control samples, respectively. Furthermore, we found 92 differential peaks of histone modification H3K4me3 are located in the promoter of 39 differentially expressed lncRNA genes and 8 differential peaks of histone modification H3K27me3 are located upstream of 7 differentially expressed lncRNA genes, which suggest that the majority of lncRNA genes may be transcriptionally regulated by histone modification in AD.

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yaqiong Wu ◽  
Jing Guo ◽  
Tongli Wang ◽  
Fuliang Cao ◽  
Guibin Wang

Abstract Background Long noncoding RNAs (lncRNAs) play an important role in diverse biological processes and have been widely studied in recent years. However, the roles of lncRNAs in leaf pigment formation in ginkgo (Ginkgo biloba L.) remain poorly understood. Results In this study, lncRNA libraries for mutant yellow-leaf and normal green-leaf ginkgo trees were constructed via high-throughput sequencing. A total of 2044 lncRNAs were obtained with an average length of 702 nt and typically harbored 2 exons. We identified 238 differentially expressed lncRNAs (DELs), 32 DELs and 49 differentially expressed mRNAs (DEGs) that constituted coexpression networks. We also found that 48 cis-acting DELs regulated 72 target genes, and 31 trans-acting DELs regulated 31 different target genes, which provides a new perspective for the regulation of the leaf-color mutation. Due to the crucial regulatory roles of lncRNAs in a wide range of biological processes, we conducted in-depth studies on the DELs and their targets and found that the chloroplast thylakoid membrane subcategory and the photosynthesis pathways (ko00195) were most enriched, suggesting their potential roles in leaf coloration mechanisms. In addition, our correlation analysis indicates that eight DELs and 68 transcription factors (TFs) might be involved in interaction networks. Conclusions This study has enriched the knowledge concerning lncRNAs and provides new insights into the function of lncRNAs in leaf-color mutations, which will benefit future selective breeding of ginkgo.


2020 ◽  
Author(s):  
B. Li ◽  
A. Ponjavic ◽  
W. H. Chen ◽  
L. Hopkins ◽  
C. Hughes ◽  
...  

AbstractDetection of single molecules in biological systems has rapidly increased in resolution over the past decade. However, delivery of single molecules has remained a challenge. Currently there is no effective method that can both introduce a precise amount of molecules onto or into a single cell at a defined position, and then image the cellular response. Here we have combined light sheet microscopy with local delivery, using a nanopipette, to accurately deliver individual proteins to a defined position. We call this method local delivery selective plane illumination microscopy (ldSPIM). ldSPIM uses a nanopipette and the ionic feedback current at the nanopipette tip to control the position from which molecules are delivered. The number of proteins delivered can be controlled by varying the voltage applied. For single-molecule detection, we implemented single-objective SPIM using a reflective atomic force microscopy cantilever to create a 2µm thin sheet. Using this setup, we demonstrate that ldSPIM can deliver single fluorescently-labeled proteins onto the plasma membrane of HK293 cells or into the cytoplasm. Next, we deposited aggregates of amyloid-β, which causes proteotoxicity relevant to Alzheimer’s disease, onto a single macrophage stably expressing a MyDD88-eGFP fusion construct. Whole-cell imaging in 3D mode enables live detection of MyDD88 accumulation and formation of MyDDosome signaling complexes, as a result of aggregate-induced triggering of toll-like receptor 4. Overall, we demonstrate a novel multifunctional imaging system capable of precise delivery of single proteins to a specific location on the cell surface or inside the cytoplasm and high-speed 3D detection at single-molecule resolution within live cells.Statement of SignificanceThis paper describes and validates a new method to study biological processes based on the controlled local delivery of molecules onto or into the cell, combined with single molecule imaging using light sheet microscopy. we not only demonstrate the instrument’s capability of delivering controlled numbers of molecules to a defined position, down to the level of single molecules, but also its potential in study of the triggering of the innate immune response by protein aggregates, a key process in the development of neurodegenerative diseases such as Alzheimer’s disease. The same approach could be applied to a wide range of other important biological processes allowing them to be followed in live cells in real-time, hence it will be of great interest to the biophysical community.


Author(s):  
Molly E. V. Swanson ◽  
Emma L. Scotter ◽  
Leon C. D. Smyth ◽  
Helen C. Murray ◽  
Brigid Ryan ◽  
...  

Abstract In Alzheimer’s disease (AD), microglia are affected by disease processes, but may also drive pathogenesis. AD pathology-associated microglial populations have been identified with single-cell RNA-Seq, but have not been validated in human brain tissue with anatomical context. Here, we quantified myeloid cell markers to identify changes in AD pathology-associated microglial populations. We performed fluorescent immunohistochemistry on normal (n = 8) and AD (n = 8) middle temporal gyri, co-labelling the pan-myeloid cell marker, Iba1, with one of 11 markers of interest (MOIs): CD45, HLA-DR, CD14, CD74, CD33, CD206, CD32, CD163, P2RY12, TMEM119, L-Ferritin. Novel image analyses quantified the single-cell abundance of Iba1 and each MOI. Each cell was gated into one Iba1-MOI population (Iba1low MOIhigh, Iba1high MOIhigh, or Iba1high MOIlow) and the abundance of each population was compared between AD and control. Triple-labelling of L-Ferritin and Iba1 with a subset of MOIs was performed to investigate L-Ferritin-MOI co-expression on Iba1low cells. Iba1low MOIhigh myeloid cell populations delineated by MOIs CD45, HLA-DR, CD14, CD74, CD33, CD32, and L-Ferritin were increased in AD. Further investigation of the Iba1low MOIhigh populations revealed that their abundances correlated with tau, but not amyloid beta, load in AD. The Iba1low microglial population highly expressed L-Ferritin, reflecting microglial dysfunction. The L-Ferritinhigh CD74high HLA-DRhigh phenotype of the Iba1low population mirrors that of a human AD pathology-associated microglial subpopulation previously identified using single-cell RNA-Seq. Our high-throughput immunohistochemical data with anatomical context support the microglial dysfunction hypothesis of AD.


Author(s):  
Burbaeva G.Sh. ◽  
Androsova L.V. ◽  
Vorobyeva E.A. ◽  
Savushkina O.K.

The aim of the study was to evaluate the rate of polymerization of tubulin into microtubules and determine the level of colchicine binding (colchicine-binding activity of tubulin) in the prefrontal cortex in schizophrenia, vascular dementia (VD) and control. Colchicine-binding activity of tubulin was determined by Sherlinе in tubulin-enriched extracts of proteins from the samples. Measurement of light scattering during the polymerization of the tubulin was carried out using the nephelometric method at a wavelength of 450-550 nm. There was a significant decrease in colchicine-binding activity and the rate of tubulin polymerization in the prefrontal cortex in both diseases, and in VD to a greater extent than in schizophrenia. The obtained results suggest that not only in Alzheimer's disease, but also in other mental diseases such as schizophrenia and VD, there is a decrease in the level of tubulin in the prefrontal cortex of the brain, although to a lesser extent than in Alzheimer's disease, and consequently the amount of microtubules.


Author(s):  
Georgiana Uță ◽  
Denisa Ștefania Manolescu ◽  
Speranța Avram

Background.: Currently, the pharmacological management in Alzheimer's disease is based on several chemical structures, represented by acetylcholinesterase and N-methyl-D-aspartate (NMDA) receptor ligands, with still unclear molecular mechanisms, but severe side effects. For this reason, a challenge for Alzheimer's disease treatment remains to identify new drugs with reduced side effects. Recently, the natural compounds, in particular certain chemical compounds identified in the essential oil of peppermint, sage, grapes, sea buckthorn, have increased interest as possible therapeutics. Objectives.: In this paper, we have summarized data from the recent literature, on several chemical compounds extracted from Salvia officinalis L., with therapeutic potential in Alzheimer's disease. Methods.: In addition to the wide range of experimental methods performed in vivo and in vitro, also we presented some in silico studies of medicinal compounds. Results. Through this mini-review, we present the latest information regarding the therapeutic characteristics of natural compounds isolated from Salvia officinalis L. in Alzheimer's disease. Conclusion.: Thus, based on the information presented, we can say that phytotherapy is a reliable therapeutic method in a neurodegenerative disease.


2021 ◽  
pp. 1-22
Author(s):  
Mariana Van Zeller ◽  
Diogo M. Dias ◽  
Ana M. Sebastião ◽  
Cláudia A. Valente

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disease commonly diagnosed among the elderly population. AD is characterized by the loss of synaptic connections, neuronal death, and progressive cognitive impairment, attributed to the extracellular accumulation of senile plaques, composed by insoluble aggregates of amyloid-β (Aβ) peptides, and to the intraneuronal formation of neurofibrillary tangles shaped by hyperphosphorylated filaments of the microtubule-associated protein tau. However, evidence showed that chronic inflammatory responses, with long-lasting exacerbated release of proinflammatory cytokines by reactive glial cells, contribute to the pathophysiology of the disease. NLRP3 inflammasome (NLRP3), a cytosolic multiprotein complex sensor of a wide range of stimuli, was implicated in multiple neurological diseases, including AD. Herein, we review the most recent findings regarding the involvement of NLRP3 in the pathogenesis of AD. We address the mechanisms of NLRP3 priming and activation in glial cells by Aβ species and the potential role of neurofibrillary tangles and extracellular vesicles in disease progression. Neuronal death by NLRP3-mediated pyroptosis, driven by the interneuronal tau propagation, is also discussed. We present considerable evidence to claim that NLRP3 inhibition, is undoubtfully a potential therapeutic strategy for AD.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Adeline Su Lyn Ng ◽  
Juan Wang ◽  
Kwun Kei Ng ◽  
Joanna Su Xian Chong ◽  
Xing Qian ◽  
...  

Abstract Background Alzheimer’s disease (AD) and behavioral variant frontotemporal dementia (bvFTD) cause distinct atrophy and functional disruptions within two major intrinsic brain networks, namely the default network and the salience network, respectively. It remains unclear if inter-network relationships and whole-brain network topology are also altered and underpin cognitive and social–emotional functional deficits. Methods In total, 111 participants (50 AD, 14 bvFTD, and 47 age- and gender-matched healthy controls) underwent resting-state functional magnetic resonance imaging (fMRI) and neuropsychological assessments. Functional connectivity was derived among 144 brain regions of interest. Graph theoretical analysis was applied to characterize network integration, segregation, and module distinctiveness (degree centrality, nodal efficiency, within-module degree, and participation coefficient) in AD, bvFTD, and healthy participants. Group differences in graph theoretical measures and empirically derived network community structures, as well as the associations between these indices and cognitive performance and neuropsychiatric symptoms, were subject to general linear models, with age, gender, education, motion, and scanner type controlled. Results Our results suggested that AD had lower integration in the default and control networks, while bvFTD exhibited disrupted integration in the salience network. Interestingly, AD and bvFTD had the highest and lowest degree of integration in the thalamus, respectively. Such divergence in topological aberration was recapitulated in network segregation and module distinctiveness loss, with AD showing poorer modular structure between the default and control networks, and bvFTD having more fragmented modules in the salience network and subcortical regions. Importantly, aberrations in network topology were related to worse attention deficits and greater severity in neuropsychiatric symptoms across syndromes. Conclusions Our findings underscore the reciprocal relationships between the default, control, and salience networks that may account for the cognitive decline and neuropsychiatric symptoms in dementia.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Greco ◽  
A Made' ◽  
A.S Tascini ◽  
J Garcia Manteiga ◽  
S Castelvecchio ◽  
...  

Abstract Background BACE1 encodes for β-secretase, the key enzyme involved in β-amyloid (βA) generation, a peptide well known for its involvement in Alzheimer's disease (AD). Of note, heart failure (HF) and AD share several risk factors and effectors. We recently showed that, in the heart of ischemic HF patients, the levels of both BACE1, its antisense RNA BACE1-AS and βA are all increased. BACE1-AS positively regulates the expression of BACE1, triggering βA intracellular accumulation, and its overexpression or βA administration induce cardiovascular-cell apoptosis. Aim To characterize the transcripts of the BACE1 locus and to investigate the molecular mechanisms underpinning BACE1-AS regulation of cell vitality. Methods By PCR and sequencing, we studied in the heart the expression of a variety of antisense BACE1 transcripts predicted by FANTOM CAT Epigenome. We studied BACE1 RNA stability by BrdU pulse chase experiments (BRIC assay). The cellular localization of BACE1-AS RNA was investigated by in situ hybridization assay. BACE1-AS binding RNAs were evaluated by BACE1-AS-MS2-Tag pull-down in AC16 cardiomyocytes followed by RNA-seq. Enriched RNAs were validated by qPCR and analysed by bioinformatics comparison with publicly available gene expression datasets of AD brains. Results We readily detected several antisense BACE1 transcripts expressed in AC16 cardiomyocytes; however, only BACE1-AS RNAs overlapping exon 6 of BACE1 positively regulated BACE1 mRNA levels, acting by increasing its stability. BACE1 silencing reverted cell apoptosis induced by BACE1-AS expression, indicating that BACE1 is a functional target of BACE1-AS. However, in situ hybridization experiments indicated a mainly nuclear localization for BACE1-AS, which displayed a punctuated distribution, compatible with chromatin association and indicative of potential additional targets. To identify other BACE1-AS binding RNAs, a BACE1-AS-MS2-tag pull-down was performed and RNA-seq of the enriched RNAs identified 698 BACE1-AS interacting RNAs in cardiomyocytes. Gene ontology of the BACE1-AS binding RNAs identified categories of relevance for cardiovascular or neurological diseases, such as dopaminergic synapse, glutamatergic synapse, calcium signalling pathway and voltage-gated channel activity. In spite of the differences between brain and heart transcriptomes, BACE1-AS-interacting RNAs identified in cardiomyocytes were significantly enriched in transcripts differentially expressed in AD brains as well as in RNAs expressed by enhancer genomic regions that are significantly hypomethylated in AD brains. Conclusions These data shed a new light on the complexity of BACE1-AS locus and on the existence of RNAs interacting with BACE1-AS with a potential as enhancer-RNAs. Moreover, the dysregulation of the BACE1-AS/BACE1/βA pathway may be a common disease mechanism shared by cardiovascular and neurological degenerative diseases. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Italian Health Ministery_Ricerca Corrente 2020


Sign in / Sign up

Export Citation Format

Share Document