找化学品上960化工网!
960化工网
期刊名称:BMC Molecular Biology
期刊ISSN:1471-2199
期刊官方网站:http://bmcmolbiol.biomedcentral.com/
出版商:BioMed Central Ltd.
出版周期:Monthly
影响因子:4.619
始发年份:2000
年文章数:15
是否OA:是
Laser capture microdissection for transcriptomic profiles in human skin biopsies.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2018-06-19 , DOI: 10.1186/s12867-018-0108-5
SilviaSantoro,IgnazioDiegoLopez,RaffaellaLombardi,AndreaZauli,AnaMariaOsiceanu,MelissaSorosina,FerdinandoClarelli,SilviaPeroni,DanieleCazzato,MargheritaMarchi,AngeloQuattrini,GiancarloComi,RaffaeleAdolfoCalogero,GiuseppeLauria,FilippoMartinelliBoneschi
The acquisition of reliable tissue-specific RNA sequencing data from human skin biopsy represents a major advance in research. However, the complexity of the process of isolation of specific layers from fresh-frozen human specimen by laser capture microdissection, the abundant presence of skin nucleases and RNA instability remain relevant methodological challenges. We developed and optimized a protocol to extract RNA from layers of human skin biopsies and to provide satisfactory quality and amount of mRNA sequencing data. The protocol includes steps of collection, embedding, freezing, histological coloration and relative optimization to preserve RNA extracted from specific components of fresh-frozen human skin biopsy of 14 subjects. Optimization of the protocol includes a preservation step in RNALater® Solution, the control of specimen temperature, the use of RNase Inhibitors and the time reduction of the staining procedure. The quality of extracted RNA was measured using the percentage of fragments longer than 200 nucleotides (DV200), a more suitable measurement for successful library preparation than the RNA Integrity Number (RIN). RNA was then enriched using the TruSeq® RNA Access Library Prep Kit (Illumina®) and sequenced on HiSeq® 2500 platform (Illumina®). Quality control on RNA sequencing data was adequate to get reliable data for downstream analysis. The described implemented and optimized protocol can be used for generating transcriptomics data on skin tissues, and it is potentially applicable to other tissues. It can be extended to multicenter studies, due to the introduction of an initial step of preservation of the specimen that allowed the shipment of biological samples.
Nutrient depletion and TOR inhibition induce 18S and 25S ribosomal RNAs resistant to a 5'-phosphate-dependent exonuclease in Candida albicans and other yeasts.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2018-01-19 , DOI: 10.1186/s12867-018-0102-y
JacobFleischmann,MiguelARocha
Messenger RNA (mRNA) represents a small percentage of RNAs in a cell, with ribosomal RNA (rRNA) making up the bulk of it. To isolate mRNA from eukaryotes, typically poly-A selection is carried out. Recently, a 5´-phosphate-dependent, 5´→3´ processive exonuclease called Terminator has become available. It will digest only RNA that has a 5´-monophosphate end and therefore it is very useful to eliminate most of rRNAs in cell. We have found that in the pathogenic yeast Candida albicans, while 18S and 25S components isolated from yeast in robust growth phase are easily eliminated by Terminator, those isolated from cells in the nutritionally diminished stationary phase, become resistant to digestion by this enzyme. Additional digestions with alkaline phosphatase, tobacco pyrophosphatase combined with Terminator point toward the 5′-prime end of 18S and 25S as the source of this resistance. Inhibition of TOR by rapamycin also induces resistance by these molecules. We also find that these molecules are incorporated into the ribosome and are not just produced incidentally. Finally, we show that three other yeasts show the same behavior. Digestion of RNA by Terminator has revealed 18S and 25S rRNA molecules different from the accepted processed ones seen in ribosome generation. The reason for these molecules and the underlying mechanism for their formation is unknown. The preservation of this behavior across these yeasts suggests a useful biological role for it, worthy of further inquiry.
Early growth response protein 1 regulates promoter activity of α-plasma membrane calcium ATPase 2, a major calcium pump in the brain and auditory system.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-05-22 , DOI: 10.1186/s12867-017-0092-1
RebeccaRMinich,JinLi,BruceLTempel
Along with sodium/calcium (Ca2+) exchangers, plasma membrane Ca2+ ATPases (ATP2Bs) are main regulators of intracellular Ca2+ levels. There are four ATP2B paralogs encoded by four different genes. Atp2b2 encodes the protein pump with the fastest activation, ATP2B2. In mice, the Atp2b2 transcript has several alternate transcriptional start site variants: α, β, µ and δ. These variants are expressed in developmental and tissue specific manners. The α and β Atp2b2 transcripts are equally expressed in the brain. αAtp2b2 is the only transcript found in the outer hair cells of young mice (Silverstein RS, Tempel BL. in Neuroscience 141:245–257, 2006). Mutations in the coding region of the mouse Atp2b2 gene indicate a narrow window for tolerated dysfunction of the ATP2B2 protein, specifically in the auditory system. This highlights the necessity of tight regulation of this gene for normal cell physiology. Although ATP2Bs are important regulators of Ca2+ in many cell types, little is known about their transcriptional regulation. This study identifies the proximal promoter of the αAtp2b2 transcript. Further investigations indicate that ATOH1 and EGR1 modulate promoter activity. Additionally, we report that EGR1 increases endogenous expression of Atp2b2 transcript in two cell lines. Electrophoretic mobility shift assays (EMSA) indicate that EGR1 binds to a specific site in the CpG island of the αAtp2b2 promoter. This study furthers our understanding of Atp2b2 regulation by: (I) elucidating transcriptional regulatory mechanisms for Atp2b2, and (II) identifying transcription factors that modulate expression of Atp2b2 in the brain and peripheral auditory system and (III) allows for future studies modulating gene expression of Atp2b2.
Identification of suitable reference genes for real-time quantitative PCR analysis of hydrogen peroxide-treated human umbilical vein endothelial cells.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-04-05 , DOI: 10.1186/s12867-017-0086-z
TianyiLi,HongyingDiao,LeiZhao,YueXing,JichangZhang,NingLiu,YouyouYan,XinTian,WeiSun,BinLiu
Oxidative stress can induce cell injury in vascular endothelial cells, which is the initial event in the development of atherosclerosis. Although quantitative real-time polymerase chain reaction (qRT-PCR) has been widely used in gene expression studies in oxidative stress injuries, using carefully validated reference genes has not received sufficient attention in related studies. The objective of this study, therefore, was to select a set of stably expressed reference genes for use in qRT-PCR normalization in oxidative stress injuries in human umbilical vein endothelial cells (HUVECs) induced by hydrogen peroxide (H2O2). Using geNorm analysis, we found that five stably expressed reference genes were sufficient for normalization in qRT-PCR analysis in HUVECs treated with H2O2. Genes with the most stable expression according to geNorm were U6, TFRC, RPLP0, GAPDH, and ACTB, and according to NormFinder were ALAS1, TFRC, U6, GAPDH, and ACTB. Taken together, our study demonstrated that the expression stability of reference genes may differ according to the statistical program used. U6, TFRC, RPLP0, GAPDH, and ACTB was the optimal set of reference genes for studies on gene expression performed by qRT-PCR assays in HUVECs under oxidative stress study.
Identification of microRNAs and their response to the stress of plant allelochemicals in Aphis gossypii (Hemiptera: Aphididae).
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-02-16 , DOI: 10.1186/s12867-017-0080-5
Kang-ShengMa,FenLi,YingLiu,Ping-ZhuoLiang,Xue-WeiChen,Xi-WuGao
MicroRNAs (miRNAs) are a group of short non-coding RNAs involved in the inhibition of protein translation or in mRNA degradation. Although the regulatory roles of miRNAs in various biological processes have been investigated, there is as yet an absence of studies about the regulatory roles of miRNAs involved in the metabolism of plant allelochemicals in insects. We constructed five small RNA libraries from apterous Aphis gossypii adults that had fed on an artificial diet containing various allelochemicals. Using Illumina sequencing, a total of 73.27 million clean reads was obtained, and 292 miRNAs were identified from A. gossypii. Comparative analysis of read counts indicated that both conserved and novel miRNAs were differently expressed among the five libraries, and the differential expression was validated via qRT-PCR. We found that the transcript levels of several miRNAs were increased or decreased in all of the allelochemical treatment libraries compared to the control. The putative target genes of the miRNAs were predicted using in silico tools, and the target genes of several miRNAs were presumed to be involved in the metabolism of xenobiotic compounds. Furthermore, the target prediction results were confirmed using dual luciferase reporter assay, and Ago-miR-656a-3p was demonstrated to regulate the expression of CYP6J1 post-transcriptionally through binding to the 3′ UTR of CYP6J1. Our research results indicate that miRNAs may be involved in the metabolism of plant allelochemicals in A. gossypii, and these results also represent an important new small RNA genomics resource for further studies on this topic.
Physical shearing imparts biological activity to DNA and ability to transmit itself horizontally across species and kingdom boundaries.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-08-09 , DOI: 10.1186/s12867-017-0098-8
GorantlaVenkataRaghuram,DeepikaGupta,SiddharthSubramaniam,AshwiniGaikwad,NaveenKumarKhare,MalcolmNobre,NaveenKumarNair,IndraneelMittra
We have recently reported that cell-free DNA (cfDNA) fragments derived from dying cells that circulate in blood are biologically active molecules and can readily enter into healthy cells to activate DNA damage and apoptotic responses in the recipients. However, DNA is not conventionally known to spontaneously enter into cells or to have any intrinsic biological activity. We hypothesized that cellular entry and acquisition of biological properties are functions of the size of DNA. To test this hypothesis, we generated small DNA fragments by sonicating high molecular weight DNA (HMW DNA) to mimic circulating cfDNA. Sonication of HMW DNA isolated from cancerous and non-cancerous human cells, bacteria and plant generated fragments 300–3000 bp in size which are similar to that reported for circulating cfDNA. We show here that while HMW DNAs were incapable of entering into cells, sonicated DNA (sDNA) from different sources could do so indiscriminately without heed to species or kingdom boundaries. Thus, sDNA from human cells and those from bacteria and plant could enter into nuclei of mouse cells and sDNA from human, bacterial and plant sources could spontaneously enter into bacteria. The intracellular sDNA associated themselves with host cell chromosomes and integrated into their genomes. Furthermore, sDNA, but not HMW DNA, from all four sources could phosphorylate H2AX and activate the pro-inflammatory transcription factor NFκB in mouse cells, indicating that sDNAs had acquired biological activities. Our results show that small fragments of DNA from different sources can indiscriminately enter into other cells across species and kingdom boundaries to integrate into their genomes and activate biological processes. This raises the possibility that fragmented DNA that are generated following organismal cell-death may have evolutionary implications by acting as mobile genetic elements that are involved in horizontal gene transfer.
Identification of G-quadruplex structures that possess transcriptional regulating functions in the Dele and Cdc6 CpG islands.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-06-27 , DOI: 10.1186/s12867-017-0094-z
DaniyahHBay,AnnikaBusch,FredLisdat,KeisukeIida,KazunoriIkebukuro,KazuoNagasawa,IsaoKarube,WataruYoshida
G-quadruplex is a DNA secondary structure that has been shown to play an important role in biological systems. In a previous study, we identified 1998 G-quadruplex-forming sequences using a mouse CpG islands DNA microarray with a fluorescent-labeled G-quadruplex ligand. Among these putative G-quadruplex-forming sequences, G-quadruplex formation was verified for 10 randomly selected sequences by CD spectroscopy and DMS footprinting analysis. In this study, the biological function of the 10 G-quadruplex-forming sequences in the transcriptional regulation has been analyzed using a reporter assay. When G-quadruplex-forming sequences from the Dele and Cdc6 genes have been cloned in reporter vectors carrying a minimal promoter and the luciferase gene, luciferase expression is activated. This has also been detected in experiments applying a promoterless reporter vector. Mutational analysis reveals that guanine bases, which form the G-tetrads, are important in the activation. In addition, the activation has been found to decrease by the telomestatin derivative L1H1-7OTD which can bind to the G-quadruplex DNA. When Dele and Cdc6 CpG islands, containing the G-quadruplex-forming sequence, have been cloned in the promoterless reporter vector, the luciferase expression is activated. Mutational analysis reveals that the expression level is decreased by mutation on Dele G-quadruplex; however, increased by mutation on Cdc6 G-quadruplex. Dele and Cdc6 G-quadruplex formation is significant in the transcriptional regulation. Dele and Cdc6 G-quadruplex DNA alone possess enhancer and promotor function. When studied in more complex CpG islands Dele G-quadruplex also demonstrates promotor activity, whereas Cdc6 G-quadruplex may possess a dual function of transcriptional regulation.
Selective measurement of α smooth muscle actin: why β-actin can not be used as a housekeeping gene when tissue fibrosis occurs.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-04-27 , DOI: 10.1186/s12867-017-0089-9
AporVeres-Székely,DomonkosPap,ErnaSziksz,EszterJávorszky,RékaRokonay,RitaLippai,KálmánTory,AndreaFekete,TivadarTulassay,AttilaJSzabó,ÁdámVannay
Prevalence of fibroproliferative diseases, including chronic kidney disease is rapidly increasing and has become a major public health problem worldwide. Fibroproliferative diseases are characterized by increased expression of α smooth muscle actin (α-SMA) that belongs to the family of the six conserved actin isoforms showing high degree homology. The aim of the present study was to develop real-time PCRs that clearly discriminate α-SMA and ß-actin from other actin isoforms. Real-time PCRs using self-designed mouse, human and rat specific α-SMA or ß-actin primer pairs resulted in the specific amplification of the artificial DNA templates corresponding to mouse, human or rat α-SMA or ß-actin, however ß-actin showed cross-reaction with the housekeeping γ-cyto-actin. We have shown that the use of improperly designed literary primer pairs significantly affects the results of PCRs measuring mRNA expression of α-SMA or ß-actin in the kidney of mice underwent UUO. We developed a set of carefully designed primer pairs and PCR conditions to selectively determine the expression of mouse, human or rat α-SMA and ß-actin isoforms. We demonstrated the importance of primer specificity in experiments where the results are normalized to the expression of ß-actin especially when fibrosis and thus increased expression of α-SMA is occur.
Erratum to: RUNX1 induces DNA replication independent active DNA demethylation at SPI1 regulatory regions.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-04-21 , DOI: 10.1186/s12867-017-0088-x
ShubhamGoyal,TakahiroSuzuki,Jing-RuLi,ShioriMaeda,MamiKishima,HajimeNishimura,YuriShimizu,HarukazuSuzuki
The original article [1] contained an error in the title whereby the word ‘of’ was mistakenly inserted between ‘independent’ and ‘active’ during the article’s production.As such, the original article title has now been updated to reflect the correct title. 1.Goyal S, Suzuki T, Li J-R, Maeda S, Kishima M, Nishimura H, Shimizu Y. Suzuki H RUNX1 induces DNA replication independent active DNA demethylation at SPI1 regulatory regions. BMC Mol Biol. 2017;18:9. doi:10.1186/s12867-017-0087-y.Article PubMed PubMed Central Google Scholar Download referencesSpringer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.AffiliationsDivision of Genomic Technologies, RIKEN Center for Life Science Technologies, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, JapanShubham Goyal, Takahiro Suzuki, Jing‑Ru Li, Shiori Maeda, Mami Kishima, Hajime Nishimura, Yuri Shimizu & Harukazu SuzukiAuthorsShubham GoyalView author publicationsYou can also search for this author in PubMed Google ScholarTakahiro SuzukiView author publicationsYou can also search for this author in PubMed Google ScholarJing‑Ru LiView author publicationsYou can also search for this author in PubMed Google ScholarShiori MaedaView author publicationsYou can also search for this author in PubMed Google ScholarMami KishimaView author publicationsYou can also search for this author in PubMed Google ScholarHajime NishimuraView author publicationsYou can also search for this author in PubMed Google ScholarYuri ShimizuView author publicationsYou can also search for this author in PubMed Google ScholarHarukazu SuzukiView author publicationsYou can also search for this author in PubMed Google ScholarCorresponding authorCorrespondence to Harukazu Suzuki.The online version of the original article can be found under doi:10.1186/s12867-017-0087-y. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Reprints and PermissionsCite this articleGoyal, S., Suzuki, T., Li, J. et al. Erratum to: RUNX1 induces DNA replication independent active DNA demethylation at SPI1 regulatory regions. BMC Molecular Biol 18, 11 (2017). http://doi.org/10.1186/s12867-017-0088-xDownload citationReceived: 13 April 2017Accepted: 13 April 2017Published: 21 April 2017DOI: http://doi.org/10.1186/s12867-017-0088-x
Immunoglobulin T from sea bass (Dicentrarchus labrax L.): molecular characterization, tissue localization and expression after nodavirus infection.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-03-15 , DOI: 10.1186/s12867-017-0085-0
FrancescoBuonocore,ValentinaStocchi,NoeliaNunez-Ortiz,ElisaRandelli,MarcoGerdol,AlbertoPallavicini,AngeloFacchiano,ChiaraBernini,LauraGuerra,GiuseppeScapigliati,SimonaPicchietti
Immunoglobulins (Igs) are fundamental components of the adaptive immune system of vertebrates, with the IgT/IgZ isotype specific of Teleosts. In this paper we describe the identification of an IgT heavy chain from the European sea bass (Dicentrarchus labrax L.), its molecular characterization and tissue mRNA localization by in situ hybridization. Sea bass IgT consists of 552 aa (Accession Number KM410929) and it contains a putative 19 amino acids long signal peptide and one potential N-glycosylation site. The C-region consists of four CH domains; each contains the cysteine and tryptophan residues required for their correct folding. Based on the recent sequencing of sea bass genome, we have identified five different genomic contigs bearing exons unequivocally pertaining to IgT (CH2, CH3 and CH4), but none corresponded to a complete IgH locus as IgT sequences were found in the highly fragmented assembled genomic regions which could not be assigned to any major scaffold. The 3D structure of sea bass IgT has been modelled using the crystal structure of a mouse Ig gamma as a template, thus showing that the amino acid sequence is suitable for the expected topology referred to an immunoglobulin-like architecture. The basal expression of sea bass IgT and IgM in different organs has been analysed: gut and gills, important mucosal organs, showed high IgT transcripts levels and this was the first indication of the possible involvement of sea bass IgT in mucosal immune responses. Moreover, sea bass IgT expression increased in gills and spleen after infection with nodavirus, highlighting the importance of IgT in sea bass immune responses. In situ hybridization confirmed the presence of IgT transcripts in the gut and it revealed a differential expression along the intestinal tract, with a major expression in the posterior intestine, suggesting the hindgut as a site for the recruitment of IgT+ cells in this species. IgT transcripts were also found in gill filaments and parallel lamellae and, for the first time, we identified scattered IgT positive cells in the liver, with a strong signal in the hepatic parenchyma. In conclusion, we performed a full molecular characterization of IgT in sea bass that points out its possible involvement in mucosal immune responses of this species.
Methylated site display (MSD)-AFLP, a sensitive and affordable method for analysis of CpG methylation profiles.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2017-03-09 , DOI: 10.1186/s12867-017-0083-2
ToshikiAiba,ToshiyukiSaito,AkikoHayashi,ShinjiSato,HarunobuYunokawa,ToruMaruyama,WataruFujibuchi,HisakaKurita,ChiharuTohyama,SeiichirohOhsako
It has been pointed out that environmental factors or chemicals can cause diseases that are developmental in origin. To detect abnormal epigenetic alterations in DNA methylation, convenient and cost-effective methods are required for such research, in which multiple samples are processed simultaneously. We here present methylated site display (MSD), a unique technique for the preparation of DNA libraries. By combining it with amplified fragment length polymorphism (AFLP) analysis, we developed a new method, MSD-AFLP. Methylated site display libraries consist of only DNAs derived from DNA fragments that are CpG methylated at the 5′ end in the original genomic DNA sample. To test the effectiveness of this method, CpG methylation levels in liver, kidney, and hippocampal tissues of mice were compared to examine if MSD-AFLP can detect subtle differences in the levels of tissue-specific differentially methylated CpGs. As a result, many CpG sites suspected to be tissue-specific differentially methylated were detected. Nucleotide sequences adjacent to these methyl-CpG sites were identified and we determined the methylation level by methylation-sensitive restriction endonuclease (MSRE)-PCR analysis to confirm the accuracy of AFLP analysis. The differences of the methylation level among tissues were almost identical among these methods. By MSD-AFLP analysis, we detected many CpGs showing less than 5% statistically significant tissue-specific difference and less than 10% degree of variability. Additionally, MSD-AFLP analysis could be used to identify CpG methylation sites in other organisms including humans. MSD-AFLP analysis can potentially be used to measure slight changes in CpG methylation level. Regarding the remarkable precision, sensitivity, and throughput of MSD-AFLP analysis studies, this method will be advantageous in a variety of epigenetics-based research.
Recommendations for mRNA analysis of micro-dissected glomerular tufts from paraffin-embedded human kidney biopsy samples.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2018-03-13 , DOI: 10.1186/s12867-018-0103-x
ClemensLBockmeyer,JulianeWittig,KarenSäuberlich,PhilippSelhausen,MarcEßer,PhilipZeuschner,FriedrichModde,KerstinAmann,ChristophDaniel
Glomeruli are excellent pre-determined natural structures for laser micro-dissection. Compartment-specific glomerular gene expression analysis of formalin-fixed paraffin-embedded renal biopsies could improve research applications. The major challenge for such studies is to obtain good-quality RNA from small amounts of starting material, as applicable for the analysis of glomerular compartments. In this work, we provide data and recommendations for an optimized workflow of glomerular mRNA analysis. With a proper resolution of the camera and screen provided by the next generation of micro-dissection systems, we are able to separate parietal epithelial cells from glomerular tufts. Selected compartment-specific transcripts (WT1 and GLEPP1 for glomerular tuft as well as PAX2 for parietal epithelial cells) seem to be reliable discriminators for these micro-dissected glomerular substructures. Using the phenol–chloroform extraction and hemalaun-stained sections (2 µm), high amounts of Bowman’s capsule transections (> 300) reveal sufficient RNA concentrations (> 300 ng mRNA) for further analysis. For comparison, in unstained sections from a number of 60 glomerular transections upwards, a minimum amount of 157 ng mRNA with a reasonable mRNA purity [A260/A280 ratio of 1.5 (1.4/1.7) median (25th/75th percentiles)] was reversely transcribed into cDNA. Comparing the effect of input RNA (20, 60, 150 and 300 micro-dissected glomerular transections), transcript expression of POLR2A significantly correlated when 60 and 150 laser micro-dissected glomerular transections were used for analysis. There was a lower inter-assay coefficient of variability for ADAMTS13, when at least 60 glomerular transections were used. According to the algorithms of geNormPlus and NormFinder, PGK1 and PPIA are more stable glomerular reference transcripts compared to GUSB, GAPDH, POLR2A, RPLPO, TBP, B2M, ACTB, 18SrRNA and HMBS. Our approach implements compartment-specific glomerular mRNA expression analysis into research applications, even regarding glomerular substructures like parietal epithelial cells. We recommend using of at least 60 micro-dissected unstained glomerular or 300 hemalaun-stained Bowman’s capsule transections to obtain sufficient input mRNA for reproducible results. Hereby, the range of RNA concentrations in 60 micro-dissected glomeruli is low and appropriate normalization of Cq values using our suggested reference transcripts (PGK1 and PPIA) allows compensation with respect to different amounts of RNA purity and quantity.
Development of a novel selection/counter-selection system for chromosomal gene integrations and deletions in lactic acid bacteria.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2019-03-29 , DOI: 10.1186/s12867-019-0127-x
WinschauFVanZyl,LeonMTDicks,ShellyMDeane
The underlying mechanisms by which probiotic lactic acid bacteria (LAB) enhance the health of the consumer have not been fully elucidated. Verification of probiotic modes of action can be achieved by using single- or multiple-gene knockout analyses of bacterial mutants in in vitro or in vivo models. We developed a novel system based on an inducible toxin counter-selection system, allowing for rapid and efficient isolation of LAB integration or deletion mutants. The Lactococcus lactis nisin A inducible promoter was used for expression of the Escherichia coli mazF toxin gene as counter-selectable marker. The flippase (FLP)/flippase recognition target (FRT) recombination system and an antisense RNA transcript were used to create markerless chromosomal gene integrations/deletions in LAB. Expression of NisR and NisK signalling proteins generated stable DNA integrations and deletions. Large sequences could be inserted or deleted in a series of steps, as demonstrated by insertion of the firefly bioluminescence gene and erythromycin resistance marker into the bacteriocin operons or adhesion genes of Lactobacillus plantarum 423 and Enterococcus mundtii ST4SA. The system was useful in the construction of L. plantarum 423 and E. mundtii ST4SA bacteriocin and adhesion gene mutants. This provides the unique opportunity to study the role of specific probiotic LAB genes in complex environments using reverse genetics analysis. Although this work focuses on two probiotic LAB strains, L. plantarum 423 and E. mundtii ST4SA, the system developed could be adapted to most, if not all, LAB species.
Transcriptomic responses to grazing reveal the metabolic pathway leading to the biosynthesis of domoic acid and highlight different defense strategies in diatoms.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2019-02-26 , DOI: 10.1186/s12867-019-0124-0
SaraHarðardóttir,SylkeWohlrab,DitteMarieHjort,BerndKrock,TorkelGisselNielsen,UweJohn,NinaLundholm
A major cause of phytoplankton mortality is predation by zooplankton. Strategies to avoid grazers have probably played a major role in the evolution of phytoplankton and impacted bloom dynamics and trophic energy transport. Certain species of the genus Pseudo-nitzschia produce the neurotoxin, domoic acid (DA), as a response to the presence of copepod grazers, suggesting that DA is a defense compound. The biosynthesis of DA comprises fusion of two precursors, a C10 isoprenoid geranyl pyrophosphate and l-glutamate. Geranyl pyrophosphate (GPP) may derive from the mevalonate isoprenoid (MEV) pathway in the cytosol or from the methyl-erythritol phosphate (MEP) pathway in the plastid. l-glutamate is suggested to derive from the citric acid cycle. Fragilariopsis, a phylogenetically related but nontoxic genus of diatoms, does not appear to possess a similar defense mechanism. We acquired information on genes involved in biosynthesis, precursor pathways and regulatory functions for DA production in the toxigenic Pseudo-nitzschia seriata, as well as genes involved in responses to grazers to resolve common responses for defense strategies in diatoms. Several genes are expressed in cells of Pseudo-nitzschia when these are exposed to predator cues. No genes are expressed in Fragilariopsis when treated similarly, indicating that the two taxa have evolved different strategies to avoid predation. Genes involved in signal transduction indicate that Pseudo-nitzschia cells receive signals from copepods that transduce cascading molecular precursors leading to the formation of DA. Five out of seven genes in the MEP pathway for synthesis of GPP are upregulated, but none in the conventional MEV pathway. Five genes with known or suggested functions in later steps of DA formation are upregulated. We conclude that no gene regulation supports that l-glutamate derives from the citric acid cycle, and we suggest the proline metabolism to be a downstream precursor. Pseudo-nitzschia cells, but not Fragilariopsis, receive and respond to copepod cues. The cellular route for the C10 isoprenoid product for biosynthesis of DA arises from the MEP metabolic pathway and we suggest proline metabolism to be a downstream precursor for l-glutamate. We suggest 13 genes with unknown function to be involved in diatom responses to grazers.
HexA is required for growth, aflatoxin biosynthesis and virulence in Aspergillus flavus.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2019-02-11 , DOI: 10.1186/s12867-019-0121-3
JunYuan,DingLi,LingQin,JiaojiaoShen,XiaodongGuo,ElisabethTumukunde,MingzhuLi,ShihuaWang
Woronin bodies are fungal-specific organelles whose formation is derived from peroxisomes. The former are believed to be involved in the regulation of mycotoxins biosynthesis, but not in their damage repair function. The hexagonal peroxisome protein (HexA or Hex1) encoded by hexA gene in Aspergillus is the main and the essential component of the Woronin body. However, little is known about HexA in Aspergillus flavus. In this study, hexA knock-out mutant (ΔhexA) and complementation strain (ΔhexAC) were produced using homologous recombination. The results showed that, ΔhexA and ΔhexAC were successfully constructed. And the data analysis indicated that the colony diameter, stress sensitivity and the sclerotia formation of A. flavus were nearly not affected by the absence of HexA. Yet, the deletion of hexA gene reduced the production of asexual spores and lessened virulence on peanuts and maize seeds markedly. In addition, it was also found that there was a significant decrease of Aflatoxin B1 production in deletion mutant, when compared to wild type. Therefore, it suggested that the hexA gene has an essential function in conidia production and secondary metabolism in A. flavus. The gene is also believed to be playing an important role in the invasion of A. flavus to the host.
Key genes differential expressions and pathway involved in salt and water-deprivation stresses for renal cortex in camel.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2019-04-08 , DOI: 10.1186/s12867-019-0129-8
YuCao,DongZhang,HuanminZhou
Camels possess the characteristics of salt- and drought-resistances, due to the long-time adaption to the living environment in desert. The camel resistance research on transcriptome is rare and deficient, especially reabsorption in renal cortex. Non-coding RNAs are normally considered as the RNA molecules that are not translated into proteins, their current roles remain mostly in regulation of information flux from DNA to protein, further on normal life activities and diseases. In order to reveal the mysterious veil of the post-transcriptional regulation of ncRNAs in renal cortex for the first time as far as we know, we designed and carried out the experiment of salt stress and water-deprivation stress in camel. By means of RNA-seq in renal cortex of Alxa Bactrian Camel (Camelus bactrianus), we identified certain significantly differential RNAs, including 4 novel lncRNAs, 11 miRNAs and 13 mRNAs under salt stress, 0 lncRNAs, 18 miRNAs and 14 mRNAs under water-deprivation stress. By data analysis, the response pathway of post-transcriptional regulation concerning salt and water-deprivation stresses was put forward, involving preventing sodium from entering the cell, purifying of water and compensating neutral amino acids by miR-193b, miR-542-5p interaction with SLC6A19 mRNA. Based on the resistance-related lncRNAs, miRNAs, and mRNAs, we proposed the post-transcriptional regulation pathway to explain how camels respond to salt and water-deprivation stresses in the ncRNAs regulation level of renal cortex for the first time, thus hoping to provide a theoretical basis for therapy of disease that is similar to high blood pressure in humans.
Overlapping transcriptional expression response of wheat zinc-induced facilitator-like transporters emphasize important role during Fe and Zn stress.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2019-09-23 , DOI: 10.1186/s12867-019-0139-6
ShivaniSharma,GazaldeepKaur,AnilKumar,VarshaMeena,JaspreetKaur,AjayKumarPandey
Hexaploid wheat is an important cereal crop that has been targeted to enhance grain micronutrient content including zinc (Zn) and iron (Fe). In this direction, modulating the expression of plant transporters involved in Fe and Zn homeostasis has proven to be one of the promising approaches. The present work was undertaken to identify wheat zinc-induced facilitator-like (ZIFL) family of transporters. The wheat ZIFL genes were characterized for their transcriptional expression response during micronutrient fluctuations and exposure to multiple heavy metals. The genome-wide analyses resulted in identification of fifteen putative TaZIFL-like genes, which were distributed only on Chromosome 3, 4 and 5. Wheat ZIFL proteins subjected to the phylogenetic analysis showed the uniform distribution along with rice, Arabidopsis and maize. In-silico analysis of the promoters of the wheat ZIFL genes demonstrated the presence of multiple metal binding sites including those which are involved in Fe and heavy metal homeostasis. Quantitative real-time PCR analysis of wheat ZIFL genes suggested the differential regulation of the transcripts in both roots and shoots under Zn surplus and also during Fe deficiency. Specifically, in roots, TaZIFL2.3, TaZIFL4.1, TaZIFL4.2, TaZIFL5, TaZIFL6.1 and TaZIFL6.2 were significantly up-regulated by both Zn and Fe. This suggested that ZIFL could possibly be regulated by both the nutrient stress in a tissue specific manner. When exposed to heavy metals, TaZIFL4.2 and TaZIFL7.1 show significant up-regulation, whereas TaZIFL5 and TaZIFL6.2 remained almost unaffected. This is the first report for detailed analysis of wheat ZIFL genes. ZIFL genes also encode for transporter of mugineic acid (TOM) proteins, that are involved in the release of phytosiderophores to enhance Fe/Zn uptake. The detailed expression analysis suggests the varying expression patterns during development of wheat seedlings and also against abiotic/biotic stresses. Overall, this study will lay foundation to prioritize functional assessment of the candidate ZIFL as a putative TOM protein in wheat.
Molecular analysis of NPAS3 functional domains and variants.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2018-12-03 , DOI: 10.1186/s12867-018-0117-4
LeiahMLuoma,FredBBerry
NPAS3 encodes a transcription factor which has been associated with multiple human psychiatric and neurodevelopmental disorders. In mice, deletion of Npas3 was found to cause alterations in neurodevelopment, as well as a marked reduction in neurogenesis in the adult mouse hippocampus. This neurogenic deficit, alongside the reduction in cortical interneuron number, likely contributes to the behavioral and cognitive alterations observed in Npas3 knockout mice. Although loss of Npas3 has been found to affect proliferation and apoptosis, the molecular function of NPAS3 is largely uncharacterized outside of predictions based on its high homology to bHLH–PAS transcription factors. Here we set out to characterize NPAS3 as a transcription factor, and to confirm whether NPAS3 acts as predicted for a Class 1 bHLH–PAS family member. Through these studies we have experimentally demonstrated that NPAS3 behaves as a true transcription factor, capable of gene regulation through direct association with DNA. NPAS3 and ARNT are confirmed to directly interact in human cells through both bHLH and PAS dimerization domains. The C-terminus of NPAS3 was found to contain a functional transactivation domain. Further, the NPAS3::ARNT heterodimer was shown to directly regulate the expression of VGF and TXNIP through binding of their proximal promoters. Finally, we assessed the effects of three human variants of NPAS3 on gene regulatory function and do not observe significant deficits. NPAS3 is a true transcription factor capable of regulating expression of target genes through their promoters by directly cooperating with ARNT. The tested human variants of NPAS3 require further characterization to identify their effects on NPAS3 expression and function in the individuals that carry them. These data enhance our understanding of the molecular function of NPAS3 and the mechanism by which it contributes to normal and abnormal neurodevelopment and neural function.
MiR-32-5p influences high glucose-induced cardiac fibroblast proliferation and phenotypic alteration by inhibiting DUSP1.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2019-08-22 , DOI: 10.1186/s12867-019-0135-x
JieShen,WanhongXing,RuiLiu,YiyingZhang,ChunhongXie,FangqiGong
The current study aimed to investigate the effects of miR-32-5p on cardiac fibroblasts (CFs) that were induced with high levels of glucose; we also aimed to identify the potential mechanisms involved in the regulation of DUSP1 expression. Human CFs were transfected with a miR-32-5p inhibitor or mimic and were treated with a normal concentration or a high concentration of glucose. Flow cytometry analysis was performed to identify cardiac fibroblasts by examining vimentin, fibronectin (FN) and α-actin expression in human CFs. qRT-PCR and western blot assays were performed to confirm the expression of miR-32-5p, DUSP1 and cardiac fibrosis relevant proteins. The proliferation of CFs was assessed by using MTT assay. An immunocytofluorescent staining assay was performed to determine the protein level of α-SMA and to investigate the degree of phenotypic changes in human CFs. The specific relationship between miR-32-5p and DUSP1 was investigated by a dual luciferase reporter assay. Cell apoptosis rates were measured with flow cytometry and the annexin V-FITC and propidine iodide (PI) staining method. A luciferase reporter assay indicated that miR-32-5p could directly target DUSP1. High glucose levels resulted in the overexpression of miR-32-5p, which downregulated DUSP1 expression. Both the upregulation of miR-32-5p and the downregulation of DUSP1 promoted cell apoptosis, proliferation and phenotypic changes in human CFs. All findings in this study provide further evidence for the positive effects of miR-32-5p on cell proliferation and the phenotypic changes in CFs by inhibiting DUSP1 expression, and reveal that miR-32-5p could serve as prognostic diagnostic target for cardiac fibrosis.
Analyses of changes in myocardial long non-coding RNA and mRNA profiles after severe hemorrhagic shock and resuscitation via RNA sequencing in a rat model.
BMC Molecular Biology ( IF 4.619 ) Pub Date : 2018-11-01 , DOI: 10.1186/s12867-018-0113-8
LinLin,ZhengfeiYang,GuanghuiZheng,YongxunZhuansun,YueWang,JianguoLi,RuiChen,WanchunTang
Ischemia–reperfusion injury has been proven to induce organ dysfunction and death, although the mechanism is not fully understood. Long non-coding RNAs (lncRNAs) have drawn wide attention with their important roles in the gene expression of some biological processes and diseases, including myocardial ischemia–reperfusion (I/R) injury. In this paper, a total of 26 Sprague–Dawley (SD) rats were randomized into two groups: sham and ischemia–reperfusion (I/R) injury. Hemorrhagic shock was induced by removing 45% of the estimated total blood volume followed by reinfusion of shed blood. High-throughput RNA sequencing was used to analyze differentially expressed (DE) lncRNAs and messenger RNAs (mRNAs) in the heart tissue 4 h after reperfusion. Myocardial function was also evaluated. After resuscitation, the decline of myocardial function of shocked animals, expressed by cardiac output, ejection fraction, and myocardial performance index (MPI), was significant (p  中文翻译: 通过大鼠模型中的RNA测序分析严重失血性休克和复苏后心肌长非编码RNA和mRNA的长时程变化。 缺血再灌注损伤已被证明可导致器官功能障碍和死亡,尽管其机理尚不完全清楚。长的非编码RNA(lncRNA)在某些生物过程和疾病(包括心肌缺血再灌注(I / R)损伤)的基因表达中的重要作用已引起广泛关注。本文共将26只Sprague-Dawley(SD)大鼠随机分为两组:假手术和缺血再灌注(I / R)损伤。出血性休克是通过去除估计总血容量的45%,然后重新注入流血引起的。高通量RNA测序用于分析再灌注后4 h心脏组织中的差异表达(DE)lncRNA和信使RNA(mRNA)。还评估了心肌功能。复苏后 以心输出量,射血分数和心肌性能指数(MPI)表示的休克动物心肌功能的下降是显着的(p <0.05)。通过倍数变化的绝对值≥2和错误发现率≤0.001鉴定DE lncRNA和mRNA。与假手术组相比,在I / R损伤组的大鼠中,851个lncRNA和1015 mRNA显着上调,而1533个lncRNA和1702 m RNA显着下调。在DE lncRNA中,我们发现了12个与一些已知的凋亡相关蛋白编码基因相关的位置,这些基因相应地被上调或下调,包括STAT3和Il1r1。实时PCR分析证实了五种与位置相关的lncRNA(NONRATT006032.2,NONRATT006033.2,NONRATT006034.2,NONRATT006035.2和NONRATT029969)的表达水平。2)与假手术组相比,I / R损伤组大鼠中它们的位置相关mRNA(STAT3和Il1r1)均明显上调。DE lncRNAs(NONRATT006032.2,NONRATT006033.2,NONRATT006034.2和NONRATT006035.2)可以通过在失血性休克和复苏后刺激共同定位的基因(STAT3)来与其在心肌保护中的作用兼容。I / R损伤的最终预后可能受到不同基因的调节,这被认为是一个复杂的网络。2)可以通过在失血性休克和复苏后刺激其共同定位的基因(STAT3)来与其在心肌保护中的作用兼容。I / R损伤的最终预后可能受到不同基因的调控,这被认为是一个复杂的网络。2)通过在失血性休克和复苏后刺激其共同定位的基因(STAT3),可能与其在心肌保护中的作用相适应。I / R损伤的最终预后可能受到不同基因的调控,这被认为是一个复杂的网络。
中科院SCI期刊分区
大类学科 小类学科 TOP 综述
生物3区 BIOCHEMISTRY & MOLECULAR BIOLOGY 生化与分子生物学4区
补充信息
自引率 H-index SCI收录状况 PubMed Central (PML)
0.00 61 Science Citation Index Expanded
投稿指南
期刊投稿网址
http://www.editorialmanager.com/bmmi/default.aspx
投稿指南
http://bmcmolbiol.biomedcentral.com/submission-guidelines
投稿模板
http://bmcmolbiol.biomedcentral.com/submission-guidelines/preparing-your-manuscript
参考文献格式
http://bmcmolbiol.biomedcentral.com/submission-guidelines/preparing-your-manuscript
收稿范围
BMC Molecular Biology is an open access journal publishing original peer-reviewed research articles in all aspects of DNA and RNA in a cellular context, encompassing investigations of chromatin, replication, recombination, mutation, repair, transcription, translation and RNA processing and function.
收录载体
Research article Methodology article Database article Software article
平台客服
平台客服
平台在线客服