1
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Bianco CM, Caballero-Rothar NN, Ma X, Farley KR, Vanderpool CK. Transcriptional and post-transcriptional mechanisms modulate cyclopropane fatty acid synthase through small RNAs in Escherichia coli. J Bacteriol 2024:e0004924. [PMID: 38980083 DOI: 10.1128/jb.00049-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Accepted: 06/12/2024] [Indexed: 07/10/2024] Open
Abstract
The small RNA (sRNA) RydC strongly activates cfa, which encodes the cyclopropane fatty acid synthase. Previous work demonstrated that RydC activation of cfa increases the conversion of unsaturated fatty acids to cyclopropanated fatty acids in membrane lipids and changes the biophysical properties of membranes, making cells more resistant to acid stress. The regulators that control RydC synthesis had not previously been identified. In this study, we identify a GntR-family transcription factor, YieP, that represses rydC transcription. YieP positively autoregulates its own transcription and indirectly regulates cfa through RydC. We further identify additional sRNA regulatory inputs that contribute to the control of RydC and cfa. The translation of yieP is repressed by the Fnr-dependent sRNA, FnrS, making FnrS an indirect activator of rydC and cfa. Conversely, RydC activity on cfa is antagonized by the OmpR-dependent sRNA OmrB. Altogether, this work illuminates a complex regulatory network involving transcriptional and post-transcriptional inputs that link the control of membrane biophysical properties to multiple environmental signals. IMPORTANCE Bacteria experience many environmental stresses that challenge their membrane integrity. To withstand these challenges, bacteria sense what stress is occurring and mount a response that protects membranes. Previous work documented the important roles of small RNA (sRNA) regulators in membrane stress responses. One sRNA, RydC, helps cells cope with membrane-disrupting stresses by promoting changes in the types of lipids incorporated into membranes. In this study, we identified a regulator, YieP, that controls when RydC is produced and additional sRNA regulators that modulate YieP levels and RydC activity. These findings illuminate a complex regulatory network that helps bacteria sense and respond to membrane stress.
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Affiliation(s)
- Colleen M Bianco
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | | | - Xiangqian Ma
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Kristen R Farley
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Carin K Vanderpool
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
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2
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Weinfurter JT, Bennett SN, Reynolds MR. A SMART method for isolating monoclonal antibodies from individual rhesus macaque memory B cells. J Immunol Methods 2024; 525:113602. [PMID: 38103783 PMCID: PMC10842827 DOI: 10.1016/j.jim.2023.113602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 11/07/2023] [Accepted: 12/09/2023] [Indexed: 12/19/2023]
Abstract
Characterizing antigen-specific B cells is a critical component of vaccine and infectious disease studies in rhesus macaques (RMs). However, it is challenging to capture immunoglobulin variable (IgV) genes from individual RM B cells using 5' multiplex (MTPX) primers in nested PCR reactions. In particular, the diversity within RM IgV gene leader sequences necessitates large 5' MTPX primer sets to amplify IgV genes, decreasing PCR efficiency. To address this problem, we developed a switching mechanism at the 5' ends of the RNA transcript (SMART)-based method for amplifying IgV genes from single RM B cells to capture Ig heavy and light chain pairs. We demonstrate this technique by isolating simian immunodeficiency virus (SIV) envelope-specific antibodies from single-sorted RM memory B cells. This approach has several advantages over existing methods for cloning antibodies from RMs. First, optimized PCR conditions and SMART 5' and 3' rapid amplification of cDNA ends (RACE) reactions generate full-length cDNAs from individual B cells. Second, it appends synthetic primer binding sites to the 5' and 3' ends of cDNA during synthesis, allowing for PCR amplification of low-abundance antibody templates. Third, the nested PCR primer mixes are simplified by employing universal 5' primers, eliminating the need for complex 5' MTPX primer sets. We anticipate this method will enhance the isolation of antibodies from individual RM B cells, supporting the genetic and functional characterization of antigen-specific B cells.
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Affiliation(s)
- Jason T Weinfurter
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, United States of America
| | - Sarah N Bennett
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, United States of America
| | - Matthew R Reynolds
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, United States of America; Wisconsin National Primate Research Center, University of Wisconsin, Madison, WI, United States of America.
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3
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Mitiushkina NV, Tiurin VI, Anuskina AA, Bordovskaya NA, Shestakova AD, Martianov AS, Bubnov MG, Shishkina AS, Semina MV, Romanko AA, Kuligina ES, Imyanitov EN. Molecular Analysis of Biliary Tract Cancers with the Custom 3' RACE-Based NGS Panel. Diagnostics (Basel) 2023; 13:3168. [PMID: 37891989 PMCID: PMC10605186 DOI: 10.3390/diagnostics13203168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 10/05/2023] [Accepted: 10/08/2023] [Indexed: 10/29/2023] Open
Abstract
The technique 3' rapid amplification of cDNA ends (3' RACE) allows for detection of translocations with unknown gene partners located at the 3' end of the chimeric transcript. We composed a 3' RACE-based RNA sequencing panel for the analysis of FGFR1-4 gene rearrangements, detection of activating mutations located within FGFR1-4, IDH1/2, ERBB2 (HER2), KRAS, NRAS, BRAF, and PIK3CA genes, and measurement of the expression of ERBB2, PD-L1, and FGFR1-4 transcripts. This NGS panel was utilized for the molecular profiling of 168 biliary tract carcinomas (BTCs), including 83 intrahepatic cholangiocarcinomas (iCCAs), 44 extrahepatic cholangiocarcinomas (eCCAs), and 41 gallbladder adenocarcinomas (GBAs). The NGS failure rate was 3/168 (1.8%). iCCAs, but not other categories of BTCs, were characterized by frequent FGFR2 alterations (17/82, 20.7%) and IDH1/2 mutations (23/82, 28%). Other potentially druggable events included ERBB2 amplifications or mutations (7/165, 4.2% of all successfully analyzed BTCs) and BRAF p.V600E mutations (3/165, 1.8%). In addition to NGS, we analyzed microsatellite instability (MSI) using the standard five markers and revealed this event in 3/158 (1.9%) BTCs. There were no instances of ALK, ROS1, RET, and NTRK1-3 gene rearrangements or MET exon 14 skipping mutations. Parallel analysis of 47 iCCA samples with the Illumina TruSight Tumor 170 kit confirmed good performance of our NGS panel. In conclusion, targeted RNA sequencing coupled with the 3' RACE technology is an efficient tool for the molecular diagnostics of BTCs.
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Affiliation(s)
- Natalia V. Mitiushkina
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Vladislav I. Tiurin
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Aleksandra A. Anuskina
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Natalia A. Bordovskaya
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Anna D. Shestakova
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Aleksandr S. Martianov
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
- Department of Medical Genetics, St.-Petersburg Pediatric Medical University, 194100 St. Petersburg, Russia
| | - Mikhail G. Bubnov
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Anna S. Shishkina
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Maria V. Semina
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Aleksandr A. Romanko
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
| | - Ekaterina S. Kuligina
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
- Department of Medical Genetics, St.-Petersburg Pediatric Medical University, 194100 St. Petersburg, Russia
| | - Evgeny N. Imyanitov
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, 197758 St. Petersburg, Russia; (N.V.M.); (N.A.B.); (A.S.S.); (M.V.S.); (A.A.R.); (E.S.K.)
- Department of Medical Genetics, St.-Petersburg Pediatric Medical University, 194100 St. Petersburg, Russia
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4
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Weinfurter JT, Bennett SN, Reynolds M. A SMART method for efficiently isolating monoclonal antibodies from individual rhesus macaque memory B cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.02.543510. [PMID: 37333083 PMCID: PMC10274751 DOI: 10.1101/2023.06.02.543510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Characterizing antigen-specific B cells is a critical component of vaccine and infectious disease studies in rhesus macaques (RMs). However, it is challenging to capture immunoglobulin variable (IgV) genes from individual RM B cells using 5' multiplex (MTPX) primers in nested PCR reactions. In particular, the diversity within RM IgV gene leader sequences necessitates the use of large 5' MTPX primer sets to amplify IgV genes, decreasing PCR efficiency. To address this problem, we developed a switching mechanism at the 5' ends of the RNA transcript (SMART)-based method for amplifying IgV genes from single RM B cells, providing unbiased capture of Ig heavy and light chain pairs for cloning antibodies. We demonstrate this technique by isolating simian immunodeficiency virus (SIV) envelope-specific antibodies from single-sorted RM memory B cells. This approach has several advantages over existing methods for PCR cloning antibodies from RMs. First, optimized PCR conditions and SMART 5' and 3' rapid amplification of cDNA ends (RACE) reactions generate full-length cDNAs from individual B cells. Second, it appends synthetic primer binding sites to the 5' and 3' ends of cDNA during synthesis, allowing for PCR amplification of low-abundance antibody templates. Third, universal 5' primers are employed to amplify the IgV genes from cDNA, simplifying the primer mixes in the nested PCR reactions and improving the recovery of matched heavy and light chain pairs. We anticipate this method will enhance the isolation of antibodies from individual RM B cells, supporting the genetic and functional characterization of antigen-specific B cells.
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Affiliation(s)
- Jason T. Weinfurter
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison WI
| | - Sarah N. Bennett
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison WI
| | - Matthew Reynolds
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison WI
- Department of Pathology and Laboratory Medicine, School of Medicine, University of Wisconsin, Madison WI
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5
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Dauphars DJ, Wu G, Bassing CH, Krangel MS. Methods for Study of Mouse T Cell Receptor α and β Gene Rearrangements. Methods Mol Biol 2023; 2580:261-282. [PMID: 36374463 DOI: 10.1007/978-1-0716-2740-2_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Quantitative real-time PCR and next-generation sequencing (NGS) are invaluable techniques to analyze T cell receptor (Tcr) gene rearrangements in mouse lymphocyte populations. Although these approaches are powerful, they also have limitations that must be accounted for in experimental design and data interpretation. Here, we provide relevant background required for understanding these limitations and then outline established quantitative real-time PCR and NGS methods that can be used for analysis of mouse Tcra and Tcrb gene rearrangements in mice.
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Affiliation(s)
- Danielle J Dauphars
- Department of Immunology, Duke University School of Medicine, Durham, NC, USA
| | - Glendon Wu
- Immunology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Craig H Bassing
- Immunology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
- Department of Pathology and Laboratory Medicine, Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
| | - Michael S Krangel
- Department of Immunology, Duke University School of Medicine, Durham, NC, USA.
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6
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Adamopoulos PG, Tsiakanikas P, Stolidi I, Scorilas A. A versatile 5′ RACE-Seq methodology for the accurate identification of the 5′ termini of mRNAs. BMC Genomics 2022; 23:163. [PMID: 35219290 PMCID: PMC8881849 DOI: 10.1186/s12864-022-08386-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 02/14/2022] [Indexed: 12/12/2022] Open
Abstract
Background Technological advancements in the era of massive parallel sequencing have enabled the functional dissection of the human transcriptome. However, 5′ ends of mRNAs are significantly underrepresented in these datasets, hindering the efficient analysis of the complex human transcriptome. The implementation of the template-switching mechanism at the reverse transcription stage along with 5′ rapid amplification of cDNA ends (RACE) constitutes the most prominent and efficient strategy to specify the actual 5′ ends of cDNAs. In the current study, we developed a 5′ RACE-seq method by coupling a custom template-switching and 5′ RACE assay with targeted nanopore sequencing, to accurately unveil 5′ termini of mRNA targets. Results The optimization of the described 5′ RACE-seq method was accomplished using the human BCL2L12 as control gene. We unveiled that the selection of hybrid DNA/RNA template-switching oligonucleotides as well as the complete separation of the cDNA extension incubation from the template-switching process, significantly increase the overall efficiency of the downstream 5′ RACE. Collectively, our results support the existence of two distinct 5′ termini for BCL2L12, being in complete accordance with the results derived from both direct RNA and PCR-cDNA sequencing approaches from Oxford Nanopore Technologies. As proof of concept, we implemented the described 5′ RACE-seq methodology to investigate the 5′ UTRs of several kallikrein-related peptidases (KLKs) gene family members. Our results confirmed the existence of multiple annotated 5′ UTRs of the human KLK gene family members, but also identified novel, previously uncharacterized ones. Conclusions In this work we present an in-house developed 5′ RACE-seq method, based on the template-switching mechanism and targeted nanopore sequencing. This approach enables the broad and in-depth study of 5′ UTRs of any mRNA of interest, by offering a tremendous sequencing depth, while significantly reducing the cost-per reaction compared to commercially available kits. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08386-y.
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7
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Dauphars DJ, Mihai A, Wang L, Zhuang Y, Krangel MS. Trav15-dv6 family Tcrd rearrangements diversify the Tcra repertoire. J Exp Med 2022; 219:212913. [PMID: 34910107 PMCID: PMC8679779 DOI: 10.1084/jem.20211581] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 11/04/2021] [Accepted: 12/02/2021] [Indexed: 11/20/2022] Open
Abstract
The Tcra repertoire is generated by multiple rounds of Vα-Jα rearrangement. However, Tcrd recombination precedes Tcra recombination within the complex Tcra-Tcrd locus. Here, by ablating Tcrd recombination, we report that Tcrd rearrangement broadens primary Vα use to diversify the Tcra repertoire in mice. We reveal that use of Trav15-dv6 family V gene segments in Tcrd recombination imparts diversity in the Tcra repertoire by instigating use of central and distal Vα segments. Moreover, disruption of the regions containing these genes and their cis-regulatory elements identifies the Trav15-dv6 family as being responsible for driving central and distal Vα recombinations beyond their roles as substrates for Tcrd recombination. Our study demonstrates an indispensable role for Tcrd recombination in general, and the Trav15-dv6 family in particular, in the generation of a combinatorially diverse Tcra repertoire.
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Affiliation(s)
| | - Ariana Mihai
- Department of Immunology, Duke University Medical Center, Durham, NC
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC
| | - Yuan Zhuang
- Department of Immunology, Duke University Medical Center, Durham, NC
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, NC
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8
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Erdene‐Ochir E, Shin B, Huda MN, Lee EH, Song D, Jung C, Pan C. Characterization of endogenous promoters of GapC1 and GS for recombinant protein expression in Phaeodactylum tricornutum. Microbiologyopen 2021; 10:e1239. [PMID: 34713604 PMCID: PMC8545674 DOI: 10.1002/mbo3.1239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 09/14/2021] [Indexed: 11/11/2022] Open
Abstract
Although diatoms have been utilized as a cellular factory to produce biopharmaceuticals, recombinant proteins, and biofuels, only a few numbers of gene promoters are available. Therefore, the development of novel endogenous promoters is essential for the production of a range of bioactive substances. Here, we characterized the activities of endogenous promoters glyceraldehyde-3-phosphate dehydrogenase (GapC1) and glutamine synthetase (GS) of Phaeodactylum tricornutum using green fluorescent protein (GFP) under different culture conditions. Compared with the widely used fucoxanthin chlorophyll-binding protein A (fcpA) promoter, the GS promoter constitutively drove the expression of GFP throughout all growth phases of P. tricornutum, regardless of culture conditions. Additionally, the GFP level driven by the GapC1 promoter was the highest at the log phase, similar to the fcpA promoter, and increased light and nitrogen-starvation conditions reduced GFP levels by inhibiting promoter activity. These results suggested that the GS promoter could be utilized as a strong endogenous promoter for the genetic engineering of P. tricornutum.
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Affiliation(s)
- Erdenedolgor Erdene‐Ochir
- Natural Product Informatics Research CenterKIST Gangneung Institute of Natural ProductsGangneungRepublic of Korea
- Division of Bio‐Medical Science and Technology, KIST SchoolKorea University of Science and TechnologySeoulRepublic of Korea
| | | | - Md Nazmul Huda
- Natural Product Informatics Research CenterKIST Gangneung Institute of Natural ProductsGangneungRepublic of Korea
- Division of Bio‐Medical Science and Technology, KIST SchoolKorea University of Science and TechnologySeoulRepublic of Korea
| | - Eun Ha Lee
- Natural Product Informatics Research CenterKIST Gangneung Institute of Natural ProductsGangneungRepublic of Korea
| | - Dae‐Geun Song
- Natural Product Informatics Research CenterKIST Gangneung Institute of Natural ProductsGangneungRepublic of Korea
| | - Choonkyun Jung
- Department of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and TechnologySeoul National UniversityPyeongchangRepublic of Korea
- Department of Agriculture, Forestry, and Bioresources and Integrated Major in Global Smart Farm, College of Agriculture and Life SciencesSeoul National UniversitySeoulRepublic of Korea
| | - Cheol‐Ho Pan
- Natural Product Informatics Research CenterKIST Gangneung Institute of Natural ProductsGangneungRepublic of Korea
- Division of Bio‐Medical Science and Technology, KIST SchoolKorea University of Science and TechnologySeoulRepublic of Korea
- Microalgae Ask Us Co., Ltd.GangneungRepublic of Korea
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9
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Chang CY, Wang YS, Wu JF, Yang TJ, Chang YC, Chae C, Chang HW, Hsu STD. Generation and Characterization of a Spike Glycoprotein Domain A-Specific Neutralizing Single-Chain Variable Fragment against Porcine Epidemic Diarrhea Virus. Vaccines (Basel) 2021; 9:vaccines9080833. [PMID: 34451958 PMCID: PMC8402611 DOI: 10.3390/vaccines9080833] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/26/2022] Open
Abstract
The emergence of the genotype (G) 2 and re-emergence of the G1 porcine epidemic diarrhea virus (PEDV) has caused severe economic impacts in the past decade. Developments of efficient vaccines against new variants of PEDV have been challenging, not least because of the difficulties in eliciting mucosal and lactogenic immunity. A single-chain fragment variable (scFv) capable of efficient antigen recognition is an alternative to vaccination and treatment of a viral infection. In the present study, the variable regions of the light chain and the heavy chain of a G2b PEDV spike domain A (S1A)-specific neutralizing monoclonal antibody (mAb) were sequenced, constructed with a (G4S) x3 linker, and produced by a mammalian protein expression system. Our results demonstrated that the PEDV S1A domain scFv was able to bind to S proteins of both G1 and G2b PEDVs. Nevertheless, the scFv was only capable of neutralizing the homologous G2b PEDV but not the G1 PEDV. The binding ability of the G2b-specific neutralizing scFv was not able to predict the neutralizing ability toward heterologous PEDV. The anti-PEDV S1A scFv presented herein serves as a potential therapeutic candidate against the virulent G2b PEDV.
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Affiliation(s)
- Chia-Yu Chang
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan; (C.-Y.C.); (Y.-S.W.); (T.-J.Y.)
| | - Yong-Sheng Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan; (C.-Y.C.); (Y.-S.W.); (T.-J.Y.)
- Institute of Biochemical Sciences, National Taiwan University, Taipei 10617, Taiwan
| | - Jou-Fei Wu
- Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan; (J.-F.W.); (Y.-C.C.); (H.-W.C.)
| | - Tzu-Jing Yang
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan; (C.-Y.C.); (Y.-S.W.); (T.-J.Y.)
- Institute of Biochemical Sciences, National Taiwan University, Taipei 10617, Taiwan
| | - Yen-Chen Chang
- Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan; (J.-F.W.); (Y.-C.C.); (H.-W.C.)
| | - Chanhee Chae
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea;
| | - Hui-Wen Chang
- Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan; (J.-F.W.); (Y.-C.C.); (H.-W.C.)
| | - Shang-Te Danny Hsu
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan; (C.-Y.C.); (Y.-S.W.); (T.-J.Y.)
- Institute of Biochemical Sciences, National Taiwan University, Taipei 10617, Taiwan
- Correspondence: ; Tel.: +886-2-2785-5696 (ext. 5120)
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10
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Zhao H, Li Z, Zhu Y, Bian S, Zhang Y, Qin L, Naik AK, He J, Zhang Z, Krangel MS, Hao B. A role of the CTCF binding site at enhancer Eα in the dynamic chromatin organization of the Tcra-Tcrd locus. Nucleic Acids Res 2020; 48:9621-9636. [PMID: 32853367 PMCID: PMC7515734 DOI: 10.1093/nar/gkaa711] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/03/2020] [Accepted: 08/20/2020] [Indexed: 12/25/2022] Open
Abstract
The regulation of T cell receptor Tcra gene rearrangement has been extensively studied. The enhancer Eα plays an essential role in Tcra rearrangement by establishing a recombination centre in the Jα array and a chromatin hub for interactions between Vα and Jα genes. But the mechanism of the Eα and its downstream CTCF binding site (here named EACBE) in dynamic chromatin regulation is unknown. The Hi-C data showed that the EACBE is located at the sub-TAD boundary which separates the Tcra–Tcrd locus and the downstream region including the Dad1 gene. The EACBE is required for long-distance regulation of the Eα on the proximal Vα genes, and its deletion impaired the Tcra rearrangement. We also noticed that the EACBE and Eα regulate the genes in the downstream sub-TAD via asymmetric chromatin extrusion. This study provides a new insight into the role of CTCF binding sites at TAD boundaries in gene regulation.
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Affiliation(s)
- Hao Zhao
- Guangdong Provincial Key Laboratory of Tumor Immunotherapy, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Zhaoqiang Li
- Guangdong Provincial Key Laboratory of Tumor Immunotherapy, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Yongchang Zhu
- Guangdong Provincial Key Laboratory of Tumor Immunotherapy, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Shasha Bian
- Henan Medical Genetics Institute, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan Province, China
| | - Yan Zhang
- Guangdong Provincial Key Laboratory of Tumor Immunotherapy, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Litao Qin
- Henan Medical Genetics Institute, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan Province, China
| | - Abani Kanta Naik
- Department of Immunology, Duke University Medical Center, Durham, NC, USA
| | - Jiangtu He
- State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - Zhenhai Zhang
- State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.,Center for Biomedical Informatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China.,Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, China
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, NC, USA
| | - Bingtao Hao
- Guangdong Provincial Key Laboratory of Tumor Immunotherapy, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China.,Henan Medical Genetics Institute, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan Province, China
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11
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Starkevič P, Ražanskienė A, Starkevič U, Kazanavičiūtė V, Denkovskienė E, Bendokas V, Šikšnianas T, Rugienius R, Stanys V, Ražanskas R. Isolation and Analysis of Anthocyanin Pathway Genes from Ribes Genus Reveals MYB Gene with Potent Anthocyanin-Inducing Capabilities. PLANTS 2020; 9:plants9091078. [PMID: 32842576 PMCID: PMC7570362 DOI: 10.3390/plants9091078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 01/29/2023]
Abstract
Horticultural crops of the Ribes genus are valued for their anthocyanin-rich fruits, but until now, there were no data about the genes and regulation of their flavonoid pathway. In this study, the coding sequences of flavonoid pathway enzymes and their putative regulators MYB10, bHLH3 and WD40 were isolated, and their expression analyzed in fruits with varying anthocyanin levels from different cultivars of four species belonging to the Ribes genus. Transcription levels of anthocyanin synthesis enzymes and the regulatory gene RrMYB10 correlated with fruit coloration and anthocyanin quantities of different Ribes cultivars. Regulatory genes were tested for the ability to modulate anthocyanin biosynthesis during transient expression in the leaves of two Nicotiana species and to activate Prunus avium promoters of late anthocyanin biosynthesis genes in N. tabacum. Functional tests showed a strong capability of RrMyb10 to induce anthocyanin synthesis in a heterologous system, even without the concurrent expression of any heterologous bHLH, whereas RrbHLH3 enhanced MYB-induced anthocyanin synthesis. Data obtained in this work facilitate further analysis of the anthocyanin synthesis pathway in key Ribes species, and potent anthocyanin inducer RrMyb10 can be used to manipulate anthocyanin expression in heterologous systems.
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Affiliation(s)
- Pavel Starkevič
- Department of Eukaryotic Gene Engineering, Institute of Biotechnology, Vilnius University, 10257 Vilnius, Lithuania; (P.S.); (A.R.); (U.S.); (V.K.); (E.D.)
- Nature Research Centre, Akademijos str. 2, 08412 Vilnius, Lithuania
| | - Aušra Ražanskienė
- Department of Eukaryotic Gene Engineering, Institute of Biotechnology, Vilnius University, 10257 Vilnius, Lithuania; (P.S.); (A.R.); (U.S.); (V.K.); (E.D.)
| | - Urtė Starkevič
- Department of Eukaryotic Gene Engineering, Institute of Biotechnology, Vilnius University, 10257 Vilnius, Lithuania; (P.S.); (A.R.); (U.S.); (V.K.); (E.D.)
| | - Vaiva Kazanavičiūtė
- Department of Eukaryotic Gene Engineering, Institute of Biotechnology, Vilnius University, 10257 Vilnius, Lithuania; (P.S.); (A.R.); (U.S.); (V.K.); (E.D.)
| | - Erna Denkovskienė
- Department of Eukaryotic Gene Engineering, Institute of Biotechnology, Vilnius University, 10257 Vilnius, Lithuania; (P.S.); (A.R.); (U.S.); (V.K.); (E.D.)
| | - Vidmantas Bendokas
- Department of Orchard Plant Genetics and Biotechnology, Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, 54333 Babtai, Lithuania; (V.B.); (T.Š.); (R.R.); (V.S.)
| | - Tadeušas Šikšnianas
- Department of Orchard Plant Genetics and Biotechnology, Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, 54333 Babtai, Lithuania; (V.B.); (T.Š.); (R.R.); (V.S.)
| | - Rytis Rugienius
- Department of Orchard Plant Genetics and Biotechnology, Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, 54333 Babtai, Lithuania; (V.B.); (T.Š.); (R.R.); (V.S.)
| | - Vidmantas Stanys
- Department of Orchard Plant Genetics and Biotechnology, Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, 54333 Babtai, Lithuania; (V.B.); (T.Š.); (R.R.); (V.S.)
| | - Raimundas Ražanskas
- Department of Eukaryotic Gene Engineering, Institute of Biotechnology, Vilnius University, 10257 Vilnius, Lithuania; (P.S.); (A.R.); (U.S.); (V.K.); (E.D.)
- Correspondence:
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12
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Wulf MG, Maguire S, Humbert P, Dai N, Bei Y, Nichols NM, Corrêa IR, Guan S. Non-templated addition and template switching by Moloney murine leukemia virus (MMLV)-based reverse transcriptases co-occur and compete with each other. J Biol Chem 2019; 294:18220-18231. [PMID: 31640989 PMCID: PMC6885630 DOI: 10.1074/jbc.ra119.010676] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 10/17/2019] [Indexed: 11/21/2022] Open
Abstract
Single-cell RNA-Seq (scRNA-Seq) has led to an unprecedented understanding of gene expression and regulation in individual cells. Many scRNA-Seq approaches rely upon the template switching property of Moloney murine leukemia virus (MMLV)-type reverse transcriptases. Template switching is believed to happen in a sequential process involving nontemplated addition of three protruding nucleotides (+CCC) to the 3′-end of the nascent cDNA, which can then anneal to the matching rGrGrG 3′-end of the template-switching oligo (TSO), allowing the reverse transcriptase (RT) to switch templates and continue copying the TSO sequence. In this study, we present a detailed analysis of template switching biases with respect to the RNA template, specifically of the role of the sequence and nature of its 5′-end (capped versus noncapped) in these biases. Our findings confirmed that the presence of a 5′-m7G cap enhances template switching efficiency. We also profiled the composition of the nontemplated addition in the absence of TSO and observed that the 5′-end of RNA template influences the terminal transferase activity of the RT. Furthermore, we found that designing new TSOs that pair with the most common nontemplated additions did little to improve template switching efficiency. Our results provide evidence suggesting that, in contrast to the current understanding of the template switching process, nontemplated addition and template switching are concurrent and competing processes.
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Affiliation(s)
| | - Sean Maguire
- New England Biolabs, Inc., Ipswich, Massachusetts 01938
| | - Paul Humbert
- New England Biolabs, Inc., Ipswich, Massachusetts 01938
| | - Nan Dai
- New England Biolabs, Inc., Ipswich, Massachusetts 01938
| | - Yanxia Bei
- New England Biolabs, Inc., Ipswich, Massachusetts 01938
| | | | - Ivan R Corrêa
- New England Biolabs, Inc., Ipswich, Massachusetts 01938.
| | - Shengxi Guan
- New England Biolabs, Inc., Ipswich, Massachusetts 01938.
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13
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Bhardwaj V, Semplicio G, Erdogdu NU, Manke T, Akhtar A. MAPCap allows high-resolution detection and differential expression analysis of transcription start sites. Nat Commun 2019; 10:3219. [PMID: 31363093 PMCID: PMC6667505 DOI: 10.1038/s41467-019-11115-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 06/20/2019] [Indexed: 01/06/2023] Open
Abstract
The position, shape and number of transcription start sites (TSS) are critical determinants of gene regulation. Most methods developed to detect TSSs and study promoter usage are, however, of limited use in studies that demand quantification of expression changes between two or more groups. In this study, we combine high-resolution detection of transcription start sites and differential expression analysis using a simplified TSS quantification protocol, MAPCap (Multiplexed Affinity Purification of Capped RNA) along with the software icetea. Applying MAPCap on developing Drosophila melanogaster embryos and larvae, we detected stage and sex-specific promoter and enhancer activity and quantify the effect of mutants of maleless (MLE) helicase at X-chromosomal promoters. We observe that MLE mutation leads to a median 1.9 fold drop in expression of X-chromosome promoters and affects the expression of several TSSs with a sexually dimorphic expression on autosomes. Our results provide quantitative insights into promoter activity during dosage compensation. The position, shape and number of transcription start sites (TSS) regulate gene expression. Here authors present MAPCap, a method for high-resolution detection and differential expression analysis of TSS, and apply MAPCap to early fly development, detecting stage and sex-specific promoter and enhancer activity.
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Affiliation(s)
- Vivek Bhardwaj
- Max Planck Institute for Immunobiology and Epigenetics, 79108, Freiburg, Germany.,Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany
| | - Giuseppe Semplicio
- Max Planck Institute for Immunobiology and Epigenetics, 79108, Freiburg, Germany
| | - Niyazi Umut Erdogdu
- Max Planck Institute for Immunobiology and Epigenetics, 79108, Freiburg, Germany.,Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany
| | - Thomas Manke
- Max Planck Institute for Immunobiology and Epigenetics, 79108, Freiburg, Germany
| | - Asifa Akhtar
- Max Planck Institute for Immunobiology and Epigenetics, 79108, Freiburg, Germany.
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14
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A novel picornavirus in feces of a rainbow lorikeet (Trichoglossus moluccanus) shows a close relationship to members of the genus Avihepatovirus. Arch Virol 2019; 164:1911-1914. [PMID: 30982088 DOI: 10.1007/s00705-019-04246-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 03/11/2019] [Indexed: 10/27/2022]
Abstract
A novel picornavirus, named "lorikeet picornavirus 1" (LoPV-1), was detected in a fecal sample from rainbow lorikeets using viral metagenomic analysis, and its complete genome sequence was determined and analyzed. The genome of LoPV-1 is 7862 nt long, including a 617-nt 5' UTR, a type IV IRES 5'UTR with an '8-like' motif, a 7032-nt polyprotein ORF, and a 213-nt 3' UTR. Phylogenetic analysis and pairwise asequence comparisons based on the amino acid sequences of P1, P2, and P3 indicated that LoPV-1 showed the closest relationship to two picornaviruses that were isolated recently from red-crowned cranes and clustered together with members of the genus Avihepatovirus.
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15
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Nelson C, Ambros V. Trans-splicing of the C. elegans let-7 primary transcript developmentally regulates let-7 microRNA biogenesis and let-7 family microRNA activity. Development 2019; 146:dev172031. [PMID: 30770392 PMCID: PMC6432665 DOI: 10.1242/dev.172031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/11/2019] [Indexed: 12/19/2022]
Abstract
The sequence and roles in developmental progression of the microRNA let-7 are conserved. In general, transcription of the let-7 primary transcript (pri-let-7) occurs early in development, whereas processing of the mature let-7 microRNA arises during cellular differentiation. In Caenorhabditiselegans and other animals, the RNA-binding protein LIN-28 post-transcriptionally inhibits let-7 biogenesis at early developmental stages, but the mechanisms by which LIN-28 does this are not fully understood. Nor is it understood how the developmental regulation of let-7 might influence the expression or activities of other microRNAs of the same seed family. Here, we show that pri-let-7 is trans-spliced to the SL1 splice leader downstream of the let-7 precursor stem-loop, which produces a short polyadenylated downstream mRNA, and that this trans-splicing event negatively impacts the biogenesis of mature let-7 microRNA in cis Moreover, this trans-spliced mRNA contains sequences that are complementary to multiple members of the let-7 seed family (let-7fam) and negatively regulates let-7fam function in trans Thus, this study provides evidence for a mechanism by which splicing of a microRNA primary transcript can negatively regulate said microRNA in cis as well as other microRNAs in trans.
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Affiliation(s)
- Charles Nelson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Victor Ambros
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
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16
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Liu F, Zheng K, Chen HC, Liu ZF. Capping-RACE: a simple, accurate, and sensitive 5' RACE method for use in prokaryotes. Nucleic Acids Res 2018; 46:e129. [PMID: 30107543 PMCID: PMC6265449 DOI: 10.1093/nar/gky739] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/30/2018] [Accepted: 08/03/2018] [Indexed: 12/13/2022] Open
Abstract
Rapid amplification of cDNA ends (RACE) is a prevalent technique used to obtain the 5' ends of transcripts. Several different 5' RACE methods have been developed, and one particularly simple and efficient approach called CapFinder relies on the 5' cap-dependent template-switching that occurs in eukaryotes. However, most prokaryotic transcripts lack a 5' cap structure. Here, we report a procedure to capture primary transcripts based on capping the 5' triphosphorylated RNA in prokaryotes. Primary transcripts were first treated with vaccinia capping enzyme to add a 5' cap structure. First-strand cDNA was then synthesized using Moloney murine leukaemia virus reverse transcriptase. Finally, a template-switching oligonucleotide with a tail containing three ribonucleic acid guanines was hybridized to the cDNA 3' poly(C) and further used as template for reverse transcriptase. It is oligonucleotide sequence independent and is more sensitive compared to RLM-RACE. This approach specifically identified the transcription start sites of ompA, sodB and shiA in Escherichia coli and of ompA, rne and rppH in Brucella melitensis. Furthermore, we also successfully identified the transcription start sites of small noncoding genes ryhB and micC in E. coli and bsnc135 and bsnc149 in B. melitensis. Our findings suggest that Capping-RACE is a simple, accurate, and sensitive 5' RACE method for use in prokaryotes.
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Affiliation(s)
- Fang Liu
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Ke Zheng
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Huan-Chun Chen
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Zheng-Fei Liu
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
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17
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Lafzi A, Moutinho C, Picelli S, Heyn H. Tutorial: guidelines for the experimental design of single-cell RNA sequencing studies. Nat Protoc 2018; 13:2742-2757. [DOI: 10.1038/s41596-018-0073-y] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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18
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Carico ZM, Roy Choudhury K, Zhang B, Zhuang Y, Krangel MS. Tcrd Rearrangement Redirects a Processive Tcra Recombination Program to Expand the Tcra Repertoire. Cell Rep 2018; 19:2157-2173. [PMID: 28591585 DOI: 10.1016/j.celrep.2017.05.045] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 04/21/2017] [Accepted: 05/13/2017] [Indexed: 01/01/2023] Open
Abstract
Adaptive immunity depends on diverse T cell receptor repertoires generated by variable, diversity, and joining (V[D]J) recombination. Here, we define the principles by which combinatorial diversity is generated in the murine Tcra repertoire. Tcra and Tcrd gene segments share the Tcra-Tcrd locus, with interspersed Vα and Vδ segments undergoing Vδ-Dδ-Jδ rearrangement in CD4-CD8- thymocytes and then multiple rounds of Vα-Jα rearrangement in CD4+CD8+ thymocytes. We document stepwise, highly coordinated proximal-to-distal progressions of Vα and Jα use on individual Tcra alleles, limiting combinatorial diversity. This behavior is supported by an extended chromatin conformation in CD4+CD8+ thymocytes, with only nearby Vα and Jα segments contacting each other. Tcrd rearrangements can use distal Vδ segments due to a contracted Tcra-Tcrd conformation in CD4-CD8- thymocytes. These rearrangements expand the Tcra repertoire by truncating the Vα array to permit otherwise disfavored Vα-Jα combinations. Therefore, recombination events at two developmental stages with distinct chromatin conformations synergize to promote Tcra repertoire diversity.
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Affiliation(s)
- Zachary M Carico
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Kingshuk Roy Choudhury
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
| | - Baojun Zhang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Yuan Zhuang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA.
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19
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Melnik S, Neumann AC, Karongo R, Dirndorfer S, Stübler M, Ibl V, Niessner R, Knopp D, Stoger E. Cloning and plant-based production of antibody MC10E7 for a lateral flow immunoassay to detect [4-arginine]microcystin in freshwater. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:27-38. [PMID: 28421663 PMCID: PMC5785354 DOI: 10.1111/pbi.12746] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 03/14/2017] [Accepted: 04/12/2017] [Indexed: 06/07/2023]
Abstract
Antibody MC10E7 is one of a small number of monoclonal antibodies that bind specifically to [Arg4]-microcystins, and it can be used to survey natural water sources and food samples for algal toxin contamination. However, the development of sensitive immunoassays in different test formats, particularly user-friendly tests for on-site analysis, requires a sensitive but also cost-effective antibody. The original version of MC10E7 was derived from a murine hybridoma, but we determined the sequence of the variable regions using the peptide mass-assisted cloning strategy and expressed a scFv (single-chain variable fragment) format of this antibody in yeast and a chimeric full-size version in leaves of Nicotiana tabacum and Nicotiana benthamiana to facilitate inexpensive and scalable production. The specific antigen-binding activity of the purified antibody was verified by surface plasmon resonance spectroscopy and ELISA, confirming the same binding specificity as its hybridoma-derived counterpart. The plant-derived antibody was used to design a lateral flow immunoassay (dipstick) for the sensitive detection of [Arg4]-microcystins at concentrations of 100-300 ng/L in freshwater samples collected at different sites. Plant-based production will likely reduce the cost of the antibody, currently the most expensive component of the dipstick immunoassay, and will allow the development of further antibody-based analytical devices and water purification adsorbents for the efficient removal of toxic contaminants.
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Affiliation(s)
- Stanislav Melnik
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Anna-Cathrine Neumann
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Ryan Karongo
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Sebastian Dirndorfer
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Martin Stübler
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Verena Ibl
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Reinhard Niessner
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Dietmar Knopp
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Eva Stoger
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
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20
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Hopes A, Nekrasov V, Belshaw N, Grouneva I, Kamoun S, Mock T. Genome Editing in Diatoms Using CRISPR-Cas to Induce Precise Bi-allelic Deletions. Bio Protoc 2017; 7:e2625. [PMID: 34595293 PMCID: PMC8438374 DOI: 10.21769/bioprotoc.2625] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 10/21/2017] [Accepted: 11/01/2017] [Indexed: 11/02/2022] Open
Abstract
Genome editing in diatoms has recently been established for the model species Phaeodactylum tricornutum and Thalassiosira pseudonana. The present protocol, although developed for T. pseudonana, can be modified to edit any diatom genome as we utilize the flexible, modular Golden Gate cloning system. The main steps include how to design a construct using Golden Gate cloning for targeting two sites, allowing a precise deletion to be introduced into the target gene. The transformation protocol is explained, as are the methods for screening using band shift assay and/or restriction site loss.
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Affiliation(s)
- Amanda Hopes
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | | | - Nigel Belshaw
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Irina Grouneva
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Sophien Kamoun
- The Sainsbury Laboratory, Norwich Research Park, Norwich, UK
| | - Thomas Mock
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
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21
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Cañas RA, Li Z, Pascual MB, Castro-Rodríguez V, Ávila C, Sterck L, Van de Peer Y, Cánovas FM. The gene expression landscape of pine seedling tissues. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 91:1064-1087. [PMID: 28635135 DOI: 10.1111/tpj.13617] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Revised: 05/13/2017] [Accepted: 05/31/2017] [Indexed: 05/20/2023]
Abstract
Conifers dominate vast regions of the Northern hemisphere. They are the main source of raw materials for timber industry as well as a wide range of biomaterials. Despite their inherent difficulties as experimental models for classical plant biology research, the technological advances in genomics research are enabling fundamental studies on these plants. The use of laser capture microdissection followed by transcriptomic analysis is a powerful tool for unravelling the molecular and functional organization of conifer tissues and specialized cells. In the present work, 14 different tissues from 1-month-old maritime pine (Pinus pinaster) seedlings have been isolated and their transcriptomes analysed. The results increased the sequence information and number of full-length transcripts from a previous reference transcriptome and added 39 841 new transcripts. In total, 2376 transcripts were ubiquitously expressed in all of the examined tissues. These transcripts could be considered the core 'housekeeping genes' in pine. The genes have been clustered in function to their expression profiles. This analysis reduced the number of profiles to 38, most of these defined by their expression in a unique tissue that is much higher than in the other tissues. The expression and localization data are accessible at ConGenIE.org (http://v22.popgenie.org/microdisection/). This study presents an overview of the gene expression distribution in different pine tissues, specifically highlighting the relationships between tissue gene expression and function. This transcriptome atlas is a valuable resource for functional genomics research in conifers.
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Affiliation(s)
- Rafael A Cañas
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, 29071, Málaga, Spain
| | - Zhen Li
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
- Center for Plant Systems Biology, VIB, B-9052, Ghent, Belgium
- Bioinformatics Institute Ghent, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
| | - M Belén Pascual
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, 29071, Málaga, Spain
| | - Vanessa Castro-Rodríguez
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, 29071, Málaga, Spain
| | - Concepción Ávila
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, 29071, Málaga, Spain
| | - Lieven Sterck
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
- Center for Plant Systems Biology, VIB, B-9052, Ghent, Belgium
- Bioinformatics Institute Ghent, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
| | - Yves Van de Peer
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
- Center for Plant Systems Biology, VIB, B-9052, Ghent, Belgium
- Bioinformatics Institute Ghent, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
| | - Francisco M Cánovas
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, Campus Universitario de Teatinos s/n, 29071, Málaga, Spain
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22
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Noyszewski AK, Liu YC, Tamura K, Smith AG. Polymorphism and structure of style-specific arabinogalactan proteins as determinants of pollen tube growth in Nicotiana. BMC Evol Biol 2017; 17:186. [PMID: 28797243 PMCID: PMC5553597 DOI: 10.1186/s12862-017-1011-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 07/03/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pollen tube growth and fertilization are key processes in angiosperm sexual reproduction. The transmitting tract (TT) of Nicotiana tabacum controls pollen tube growth in part by secreting pistil extensin-like protein III (PELPIII), transmitting-tract-specific (TTS) protein and 120 kDa glycoprotein (120 K) into the stylar extracellular matrix. The three arabinogalactan proteins (AGP) are referred to as stylar AGPs and are the focus of this research. The transmitting tract regulates pollen tube growth, promoting fertilization or rejecting pollen tubes. RESULTS The N-terminal domain (NTD) of the stylar AGPs is proline rich and polymorphic among Nicotiana spp. The NTD was predicted to be mainly an intrinsically disordered region (IDR), making it a candidate for protein-protein interactions. The NTD is also the location for the majority of the predicted O-glycosylation sites that were variable among Nicotiana spp. The C-terminal domain (CTD) contains an Ole e 1-like domain, that was predicted to form beta-sheets that are similar in position and length among Nicotiana spp. and among stylar AGPs. The TTS protein had the greatest amino acid and predicted O-glycosylation conservation among Nicotiana spp. relative to the PELPIII and 120 K. The PELPIII, TTS and 120 K genes undergo negative selection, with dn/ds ratios of 0.59, 0.29 and 0.38 respectively. The dn/ds ratio for individual species ranged from 0.4 to 0.9 and from 0.1 to 0.8, for PELPIII and TTS genes, respectively. These data indicate that PELPIII and TTS genes are under different selective pressures. A newly discovered AGP gene, Nicotiana tabacum Proline Rich Protein (NtPRP), was found with a similar intron-exon configuration and protein structure resembling other stylar AGPs, particularly TTS. CONCLUSIONS Further studies of the NtPRP gene are necessary to elucidate its biological role. Due to its high similarity to the TTS gene, NtPRP may be involved in pollen tube guidance and growth. In contrast to TTS, both PELPIII and 120 K genes are more diverse indicating a possible role in speciation or mating preference of Nicotiana spp. We hypothesize that the stylar AGPs and NtPRP share a common origin from a single gene that duplicated and diversified into four distinct genes involved in pollen-style interactions.
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Affiliation(s)
- Andrzej K Noyszewski
- Department of Horticultural Science, University of Minnesota, 356 Alderman Hall 1970 Folwell Av., St. Paul, MN, 55108, USA.
| | - Yi-Cheng Liu
- Department of Horticultural Science, University of Minnesota, 356 Alderman Hall 1970 Folwell Av., St. Paul, MN, 55108, USA
- Present Address: Arog Pharmaceuticals, Inc, 5420 LBJ Freeway, Suite 410, Dallas, TX, 75240, USA
| | - Koichiro Tamura
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-ohsawa, Hachioji, Tokyo, 192-0397, Japan
| | - Alan G Smith
- Department of Horticultural Science, University of Minnesota, 356 Alderman Hall 1970 Folwell Av., St. Paul, MN, 55108, USA
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23
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Nelms B, Dalomba NF, Lencer W. A targeted RNAi screen identifies factors affecting diverse stages of receptor-mediated transcytosis. J Cell Biol 2017; 216:511-525. [PMID: 28069747 PMCID: PMC5294788 DOI: 10.1083/jcb.201609035] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 11/22/2016] [Accepted: 12/20/2016] [Indexed: 11/22/2022] Open
Abstract
Transcytosis plays an important role in establishing cell polarity and in mediating transport of large cargo across epithelial barriers, but its molecular basis is unclear. Nelms et al. present a new dataset of genes involved in receptor-mediated transcytosis and show that the apical and basolateral recycling and transcytotic pathways are genetically separable. Endosome transport by transcytosis is the primary mechanism by which proteins and other large cargo traverse epithelial barriers in normal tissue. Transcytosis is also essential for establishing and maintaining membrane polarity in epithelia and other polarized cells. To identify novel components of this pathway, we conducted a high-throughput RNA interference screen for factors necessary for the bidirectional transcytosis of IgG by the Fcγ receptor FcRn. This screen identified 23 genes whose suppression resulted in a reproducible decrease in FcRn-mediated transcytosis. Pulse-chase kinetic transport assays on four of the top-ranking genes (EXOC2, EXOC7, PARD6B, and LEPROT) revealed distinct effects on the apical and basolateral recycling and transcytotic pathways, demonstrating that these pathways are genetically separable. We also found a strong dependence on PARD6B for apical, but not basolateral, recycling, implicating this cell polarity gene in assembly or maintenance of the apical endosomal system. This dataset yields insights into how vesicular transport is adapted to the specialized functions of differentiated cell types and opens new research avenues into epithelial trafficking.
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Affiliation(s)
- Bradlee Nelms
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115.,Graduate Program in Biophysics, Harvard University, Cambridge, MA 02138
| | - Natasha Furtado Dalomba
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115
| | - Wayne Lencer
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115 .,Harvard Digestive Diseases Center, Boston, MA 02115
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24
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Sibley SD, Finley MA, Baker BB, Puzach C, Armién AG, Giehtbrock D, Goldberg TL. Novel reovirus associated with epidemic mortality in wild largemouth bass (Micropterus salmoides). J Gen Virol 2016; 97:2482-2487. [DOI: 10.1099/jgv.0.000568] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Samuel D. Sibley
- Department of Pathobiological Sciences, University of Wisconsin–Madison, Madison, WI, USA
| | - Megan A. Finley
- Wisconsin Department of Natural Resources, Bureau of Fisheries Management, Madison, WI, USA
| | - Bridget B. Baker
- Wisconsin Department of Natural Resources, Bureau of Fisheries Management, Madison, WI, USA
| | - Corey Puzach
- United States Fish and Wildlife Service, La Crosse Fish Health Center, Onalaska, WI, USA
| | - Aníbal G. Armién
- Minnesota Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - David Giehtbrock
- Wisconsin Department of Natural Resources, Bureau of Fisheries Management, Madison, WI, USA
| | - Tony L. Goldberg
- Global Health Institute, University of Wisconsin–Madison, Madison, Wisconsin, USA
- Department of Pathobiological Sciences, University of Wisconsin–Madison, Madison, WI, USA
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25
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Abstract
Genome-wide single-cell analysis represents the ultimate frontier of genomics research. In particular, single-cell RNA-sequencing (scRNA-seq) studies have been boosted in the last few years by an explosion of new technologies enabling the study of the transcriptomic landscape of thousands of single cells in complex multicellular organisms. More sensitive and automated methods are being continuously developed and promise to deliver better data quality and higher throughput with less hands-on time. The outstanding amount of knowledge that is going to be gained from present and future studies will have a profound impact in many aspects of our society, from the introduction of truly tailored cancer treatments, to a better understanding of antibiotic resistance and host-pathogen interactions; from the discovery of the mechanisms regulating stem cell differentiation to the characterization of the early event of human embryogenesis.
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Affiliation(s)
- Simone Picelli
- a Eukaryotic Single Cell Genomics Facility , Science for Life Laboratory , Tomtebodavägen , Solna , Sweden
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26
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Wendlandt T, Moche M, Becher D, Stöhr C. A SDD1-like subtilase is exuded by tobacco roots. FUNCTIONAL PLANT BIOLOGY : FPB 2016; 43:141-150. [PMID: 32480448 DOI: 10.1071/fp15211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 11/03/2015] [Indexed: 06/11/2023]
Abstract
Hydroponically grown tobacco (Nicotiana tabacum L. cv. Samsun) roots exude proteases under non-stressed conditions. Ten different proteases could be distinguished by 2D-zymography of root exudate. The majority of the gelatinolytic activity was susceptible to serine protease inhibitors. One of the proteases could be assigned to an EST (SGN-P361478) by mass spectrometry of immune-purified root exudate. The sequence was completed by RACE-PCR and shows typical serine protease features of subtilase family S8A. Thermostability and SDS-insensitivity indicate a kinetically stable enzyme. Phylogenetic classification of this highly gelatinolytic subtilase showed SDD1 to be the closest relative in Arabidopsis thaliana (L. Heynh.). Even closer related protein sequences could be found in other distant plant genera indicating a high conservation of the subtilase. A 5-methyltetrahydropteroyltriglutamate-homocysteine methyltransferase-like protein and suberisation-associated anionic peroxidase-like protein were co-immune-purified and identified by mass spectrometry and may constitute potential interaction partners.
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Affiliation(s)
- Tim Wendlandt
- Institute of Botany and Landscape Ecology, Ernst-Moritz-Arndt-University, Greifswald, Soldmannstrasse 15, D-17487 Greifswald, Germany
| | - Martin Moche
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Str. 15, D-17487 Greifswald, Germany
| | - Dörte Becher
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Str. 15, D-17487 Greifswald, Germany
| | - Christine Stöhr
- Institute of Botany and Landscape Ecology, Ernst-Moritz-Arndt-University, Greifswald, Soldmannstrasse 15, D-17487 Greifswald, Germany
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27
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Hopes A, Nekrasov V, Kamoun S, Mock T. Editing of the urease gene by CRISPR-Cas in the diatom Thalassiosira pseudonana. PLANT METHODS 2016; 12:49. [PMID: 27904648 PMCID: PMC5121945 DOI: 10.1186/s13007-016-0148-0] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 11/10/2016] [Indexed: 05/18/2023]
Abstract
BACKGROUND CRISPR-Cas is a recent and powerful addition to the molecular toolbox which allows programmable genome editing. It has been used to modify genes in a wide variety of organisms, but only two alga to date. Here we present a methodology to edit the genome of Thalassiosira pseudonana, a model centric diatom with both ecological significance and high biotechnological potential, using CRISPR-Cas. RESULTS A single construct was assembled using Golden Gate cloning. Two sgRNAs were used to introduce a precise 37 nt deletion early in the coding region of the urease gene. A high percentage of bi-allelic mutations (≤61.5%) were observed in clones with the CRISPR-Cas construct. Growth of bi-allelic mutants in urea led to a significant reduction in growth rate and cell size compared to growth in nitrate. CONCLUSIONS CRISPR-Cas can precisely and efficiently edit the genome of T. pseudonana. The use of Golden Gate cloning to assemble CRISPR-Cas constructs gives additional flexibility to the CRISPR-Cas method and facilitates modifications to target alternative genes or species.
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Affiliation(s)
- Amanda Hopes
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ UK
| | - Vladimir Nekrasov
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH UK
| | - Sophien Kamoun
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH UK
| | - Thomas Mock
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ UK
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28
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Starkevič P, Paukštytė J, Kazanavičiūtė V, Denkovskienė E, Stanys V, Bendokas V, Šikšnianas T, Ražanskienė A, Ražanskas R. Expression and Anthocyanin Biosynthesis-Modulating Potential of Sweet Cherry (Prunus avium L.) MYB10 and bHLH Genes. PLoS One 2015; 10:e0126991. [PMID: 25978735 PMCID: PMC4433224 DOI: 10.1371/journal.pone.0126991] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Accepted: 04/09/2015] [Indexed: 11/29/2022] Open
Abstract
Anthocyanins are essential contributors to fruit coloration, an important quality feature and a breed determining trait of a sweet cherry fruit. It is well established that the biosynthesis of anthocyanins is regulated by an interplay of specific transcription factors belonging to MYB and bHLH families accompanied by a WD40 protein. In this study, we isolated and analyzed PaWD40, PabHLH3, PabHLH33, and several closely related MYB10 gene variants from different cultivars of sweet cherry, analyzed their expression in fruits with different anthocyanin levels at several developmental stages, and determined their capabilities to modulate anthocyanin synthesis in leaves of two Nicotiana species. Our results indicate that transcription level of variant PaMYB10.1-1 correlates with fruit coloration, but anthocyanin synthesis in Nicotiana was induced by another variant, PaMYB10.1-3, which is moderately expressed in fruits. The analysis of two fruit-expressed bHLH genes revealed that PabHLH3 enhances MYB-induced anthocyanin synthesis, whereas PabHLH33 has strong inhibitory properties.
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Affiliation(s)
- Pavel Starkevič
- Vilnius University Institute of Biotechnology, V.A. Graičiūno 8, Vilnius, LT-02241, Lithuania
| | - Jurgita Paukštytė
- Vilnius University Institute of Biotechnology, V.A. Graičiūno 8, Vilnius, LT-02241, Lithuania
| | - Vaiva Kazanavičiūtė
- Vilnius University Institute of Biotechnology, V.A. Graičiūno 8, Vilnius, LT-02241, Lithuania
| | - Erna Denkovskienė
- Vilnius University Institute of Biotechnology, V.A. Graičiūno 8, Vilnius, LT-02241, Lithuania
| | - Vidmantas Stanys
- Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, Kaunas st 30, Babtai, LT-54333, Kaunas, Lithuania
| | - Vidmantas Bendokas
- Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, Kaunas st 30, Babtai, LT-54333, Kaunas, Lithuania
| | - Tadeušas Šikšnianas
- Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, Kaunas st 30, Babtai, LT-54333, Kaunas, Lithuania
| | - Aušra Ražanskienė
- Vilnius University Institute of Biotechnology, V.A. Graičiūno 8, Vilnius, LT-02241, Lithuania
| | - Raimundas Ražanskas
- Vilnius University Institute of Biotechnology, V.A. Graičiūno 8, Vilnius, LT-02241, Lithuania
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29
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nRIP-seq: a technique to identify RNA targets of an RNA binding protein on a genome-wide scale. Methods Mol Biol 2015; 1206:97-106. [PMID: 25240890 PMCID: PMC5551484 DOI: 10.1007/978-1-4939-1369-5_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Native RNA immunoprecipitation (nRIP) coupled with high-throughput sequencing (nRIP-seq) is a powerful technique that allows transcriptome-wide identification of the entire subset of coding and noncoding RNAs associated with a particular protein. Since this technology is carried out in a native condition without cross-linking, nRIP-seq detects RNAs that bind a protein directly or indirectly through a larger RNA-protein complex. Here, we use the interaction between RNA and chromatin modifiers, Polycomb proteins, as an example to describe this method. Using nRIP-seq, we provide a snapshot of Ezh2, a Polycomb component, and RNA interaction in mouse embryonic stem cells.
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30
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Hunt AG. A rapid, simple, and inexpensive method for the preparation of strand-specific RNA-Seq libraries. Methods Mol Biol 2015; 1255:195-207. [PMID: 25487215 DOI: 10.1007/978-1-4939-2175-1_17] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
High-throughput sequencing of short cDNA tags, or RNA-Seq, has become a staple of genome-wide gene expression studies in plants. RNA-Seq libraries necessarily contain tags that correspond to the mRNA-poly(A) junction, or polyadenylation site, and thus may be mined for data that can help study alternative polyadenylation. This report presents a simple, rapid, and inexpensive method for preparing strand-specific RNA-Seq libraries from varying quantities of total RNA.
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Affiliation(s)
- Arthur G Hunt
- Department of Plant and Soil Sciences, University of Kentucky, 301A Plant Science Building, 1405 Veterans Drive, Lexington, KY, 40546-0312, USA,
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31
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Xie CC, Shi J, Jia HY, Li PF, Luo Y, Cai J, Chen YH. Characterization of regulatory regions involved in the inducible expression of chiB in Bacillus thuringiensis. Arch Microbiol 2014; 197:53-63. [PMID: 25362505 DOI: 10.1007/s00203-014-1054-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 10/13/2014] [Accepted: 10/23/2014] [Indexed: 11/25/2022]
Abstract
Expression of the chiB gene from Bacillus thuringiensis Bti75 was defined as inducible by the use of transcriptional fusions with the bgaB reporter gene. The transcription start site of the chiB gene was identified as the C base located 132 base pairs upstream of the start codon. Analysis of 5' and 3' deletions of the chiB promoter region revealed that the sequence from position -192 to +36 with respect to the transcription start site was necessary for wild-type levels of inducible expression of the chiB gene. The minimal promoter region for the expression of chiB gene was identified as the sequence from position -100 to +12. Furthermore, a 16-bp sequence (designated dre) downstream of the minimal promoter region of chiB was shown to be required for chitin induction. To confirm the function of this 16-bp sequence, 25 base substitutions were introduced into the dre site. Most of the mutations resulted in constitutive expression, or the efficiency of induction decreased. All mutations identified the dre sequence as a critical site for the inducible expression of chiB. In addition, the dre site was shown to interact with a sequence-specific DNA binding factor of strain Bti75 cultured in the absence of the inducer.
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Affiliation(s)
- Chi-Chu Xie
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, People's Republic of China
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32
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Cañas RA, Canales J, Gómez-Maldonado J, Ávila C, Cánovas FM. Transcriptome analysis in maritime pine using laser capture microdissection and 454 pyrosequencing. TREE PHYSIOLOGY 2014; 34:1278-88. [PMID: 24391165 DOI: 10.1093/treephys/tpt113] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Maritime pine (Pinus pinaster Aiton) is one of the most advanced conifer models for genomics research. Conifer genomes are extremely large and major advances have recently been made in the characterization of transcriptomes. The combination of laser capture microdissection (LCM) and next-generation sequencing is a powerful tool with which to resolve the entire transcriptome of specific cell types and tissues. In the current work, we have developed a protocol for transcriptomic analyses of conifer tissue types using LCM and 454 pyrosequencing. Tissue sections were isolated using non-fixed flash-frozen samples processed by LCM. Complementary DNA synthesis and amplification from tiny amounts of total RNA from LCM samples was performed using an adapted protocol for C: onifer R: NA A: mplification (CRA+). The cDNA amplification yield and cDNA quality provided by CRA+ were adequate for 454 pyrosequencing. Furthermore, read length and quality results of the 454 runs were near the optimal parameters considered by Roche for transcriptome sequencing. Using the CRA+ protocol, non-specific amplifications were prevented, problems derived from poly(A:T) tails in the 454 sequencing technology were reduced, and read length and read number considerably enhanced. This technical approach will facilitate global gene expression analysis in individual tissues of conifers and may also be applied to other plant species.
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Affiliation(s)
- Rafael A Cañas
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Instituto Andaluz de Biotecnología, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga 29071, Spain
| | - Javier Canales
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Instituto Andaluz de Biotecnología, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga 29071, Spain
| | - Josefa Gómez-Maldonado
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Instituto Andaluz de Biotecnología, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga 29071, Spain
| | - Concepción Ávila
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Instituto Andaluz de Biotecnología, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga 29071, Spain
| | - Francisco M Cánovas
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Instituto Andaluz de Biotecnología, Universidad de Málaga, Campus Universitario de Teatinos s/n, Málaga 29071, Spain
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33
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Picelli S, Faridani OR, Björklund AK, Winberg G, Sagasser S, Sandberg R. Full-length RNA-seq from single cells using Smart-seq2. Nat Protoc 2014; 9:171-81. [PMID: 24385147 DOI: 10.1038/nprot.2014.006] [Citation(s) in RCA: 2507] [Impact Index Per Article: 250.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Emerging methods for the accurate quantification of gene expression in individual cells hold promise for revealing the extent, function and origins of cell-to-cell variability. Different high-throughput methods for single-cell RNA-seq have been introduced that vary in coverage, sensitivity and multiplexing ability. We recently introduced Smart-seq for transcriptome analysis from single cells, and we subsequently optimized the method for improved sensitivity, accuracy and full-length coverage across transcripts. Here we present a detailed protocol for Smart-seq2 that allows the generation of full-length cDNA and sequencing libraries by using standard reagents. The entire protocol takes ∼2 d from cell picking to having a final library ready for sequencing; sequencing will require an additional 1-3 d depending on the strategy and sequencer. The current limitations are the lack of strand specificity and the inability to detect nonpolyadenylated (polyA(-)) RNA.
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Affiliation(s)
| | | | - Asa K Björklund
- 1] Ludwig Institute for Cancer Research, Stockholm, Sweden. [2] Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Gösta Winberg
- 1] Ludwig Institute for Cancer Research, Stockholm, Sweden. [2] Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Sven Sagasser
- 1] Ludwig Institute for Cancer Research, Stockholm, Sweden. [2] Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Rickard Sandberg
- 1] Ludwig Institute for Cancer Research, Stockholm, Sweden. [2] Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
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34
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Zajac P, Islam S, Hochgerner H, Lönnerberg P, Linnarsson S. Base preferences in non-templated nucleotide incorporation by MMLV-derived reverse transcriptases. PLoS One 2013; 8:e85270. [PMID: 24392002 PMCID: PMC3877366 DOI: 10.1371/journal.pone.0085270] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 11/26/2013] [Indexed: 11/21/2022] Open
Abstract
Reverse transcriptases derived from Moloney Murine Leukemia Virus (MMLV) have an intrinsic terminal transferase activity, which causes the addition of a few non-templated nucleotides at the 3´ end of cDNA, with a preference for cytosine. This mechanism can be exploited to make the reverse transcriptase switch template from the RNA molecule to a secondary oligonucleotide during first-strand cDNA synthesis, and thereby to introduce arbitrary barcode or adaptor sequences in the cDNA. Because the mechanism is relatively efficient and occurs in a single reaction, it has recently found use in several protocols for single-cell RNA sequencing. However, the base preference of the terminal transferase activity is not known in detail, which may lead to inefficiencies in template switching when starting from tiny amounts of mRNA. Here, we used fully degenerate oligos to determine the exact base preference at the template switching site up to a distance of ten nucleotides. We found a strong preference for guanosine at the first non-templated nucleotide, with a greatly reduced bias at progressively more distant positions. Based on this result, and a number of careful optimizations, we report conditions for efficient template switching for cDNA amplification from single cells.
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Affiliation(s)
- Pawel Zajac
- Laboratory for Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Saiful Islam
- Laboratory for Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Hannah Hochgerner
- Laboratory for Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Peter Lönnerberg
- Laboratory for Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Sten Linnarsson
- Laboratory for Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- *
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35
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Gadkar VJ, Filion M. A linear concatenation strategy to construct 5'-enriched amplified cDNA libraries using multiple displacement amplification. Mol Biotechnol 2013; 54:541-50. [PMID: 22941734 DOI: 10.1007/s12033-012-9594-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In various experimental systems, limiting available amounts of RNA may prevent a researcher from performing large-scale analyses of gene transcripts. One way to circumvent this is to 'pre-amplify' the starting RNA/cDNA, so that sufficient amounts are available for any downstream analysis. In the present study, we report the development of a novel protocol for constructing amplified cDNA libraries using the Phi29 DNA polymerase based multiple displacement amplification (MDA) system. Using as little as 200 ng of total RNA, we developed a linear concatenation strategy to make the single-stranded cDNA template amenable for MDA. The concatenation, made possible by the template switching property of the reverse transcriptase enzyme, resulted in the amplified cDNA library with intact 5' ends. MDA generated micrograms of template, allowing large-scale polymerase chain reaction analyses or other large-scale downstream applications. As the amplified cDNA library contains intact 5' ends, it is also compatible with 5' RACE analyses of specific gene transcripts. Empirical validation of this protocol is demonstrated on a highly characterized (tomato) and an uncharacterized (corn gromwell) experimental system.
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Affiliation(s)
- Vijay J Gadkar
- Department of Biology, Université de Moncton, Moncton, Canada
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36
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Matamoros T, Barrioluengo V, Abia D, Menéndez-Arias L. Major groove binding track residues of the connection subdomain of human immunodeficiency virus type 1 reverse transcriptase enhance cDNA synthesis at high temperatures. Biochemistry 2013; 52:9318-28. [PMID: 24303887 DOI: 10.1021/bi401390x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
At high temperatures, RNA denaturation can improve the efficiency and specificity of reverse transcription. Refined structures and molecular models of HIV-1 reverse transcriptases (RTs) from phylogenetically distant clades (i.e., group M subtype B and group O) revealed a major interaction between the template-primer and the Arg³⁵⁸-Gly³⁵⁹-Ala³⁶⁰ triad in the large subunit of HIV-1M/B RT. However, fewer contacts were predicted for the equivalent Lys³⁵⁸-Ala³⁵⁹-Ser³⁶⁰ triad of HIV-1O RT and the nucleic acid. An engineered HIV-1O K358R/A359G/S360A RT showed increased cDNA synthesis efficiency above 68 °C, as determined by qualitative and quantitative reverse transcription polymerase chain reactions. In comparison with wild-type HIV-1O RT, the mutant enzyme showed higher thermal stability but retained wild-type RNase H activity. Mutations that increased the accuracy of HIV-1M/B RTs were tested in combination with the K358R/A359G/S360A triple mutation. Some of them (e.g., F61A, K65R, K65R/V75I, and V148I) had a negative effect on reverse transcription efficiency above 65 °C. RTs with improved DNA binding affinities also showed higher cDNA synthesis efficiencies at elevated temperatures. Two of the most thermostable RTs (i.e., mutants T69SSG/K358R/A359G/S360A and K358R/A359G/S360A/E478Q) showed moderately increased fidelity in forward mutation assays. Our results demonstrate that the triad of Arg³⁵⁸, Gly³⁵⁹, and Ala³⁶⁰ in the major groove binding track of HIV-1 RT is a major target for RT stabilization, and most relevant for improving reverse transcription efficiency at high temperatures.
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Affiliation(s)
- Tania Matamoros
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid , 28049 Madrid, Spain
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Harbers M, Kato S, de Hoon M, Hayashizaki Y, Carninci P, Plessy C. Comparison of RNA- or LNA-hybrid oligonucleotides in template-switching reactions for high-speed sequencing library preparation. BMC Genomics 2013; 14:665. [PMID: 24079827 PMCID: PMC3853366 DOI: 10.1186/1471-2164-14-665] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 09/24/2013] [Indexed: 11/24/2022] Open
Abstract
Background Analyzing the RNA pool or transcription start sites requires effective means to convert RNA into cDNA libraries for digital expression counting. With current high-speed sequencers, it is necessary to flank the cDNAs with specific adapters. Adding template-switching oligonucleotides to reverse transcription reactions is the most commonly used approach when working with very small quantities of RNA even from single cells. Results Here we compared the performance of DNA-RNA, DNA-LNA and DNA oligonucleotides in template-switching during nanoCAGE library preparation. Test libraries from rat muscle and HeLa cell RNA were prepared in technical triplicates and sequenced for comparison of the gene coverage and distribution of the reads within transcripts. The DNA-RNA oligonucleotide showed the highest specificity for capped 5′ ends of mRNA, whereas the DNA-LNA provided similar gene coverage with more reads falling within exons. Conclusions While confirming the cap-specific preference of DNA-RNA oligonucleotides in template-switching reactions, our data indicate that DNA-LNA hybrid oligonucleotides could potentially find other applications in random RNA sequencing.
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Affiliation(s)
- Matthias Harbers
- RIKEN Center for Life Science Technologies, Division of Genomics Technologies, Yokohama, Kanagawa 230-0045, Japan.
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Gimpel JA, Mayfield SP. Analysis of heterologous regulatory and coding regions in algal chloroplasts. Appl Microbiol Biotechnol 2012. [PMID: 23179624 DOI: 10.1007/s00253-012-4580-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The basic photosynthetic apparatus is highly conserved across all photosynthetic organisms, and this conservation can be seen in both protein composition and amino acid sequence. Conservation of regulatory elements also seems possible in chloroplast genes, as many mRNA untranslated regions (UTRs) appear to have similar structural elements. The D1 protein of Photosystem II (psbA gene) is a highly conserved core reaction center protein that shows very similar regulation from cyanobacteria through higher plants. We engineered full and partial psbA genes from a diverse set of photosynthetic organisms into a psbA deficient strain of Chlamydomonas reinhardtii. Analysis of D1 protein accumulation and photosynthetic growth revealed that coding sequences and promoters are interchangeable even between anciently diverged species. On the other hand functional recognition of 5' UTRs is limited to closely related organisms. Furthermore transformation of heterologous promoters and 5' UTRs from the atpA, tufA and psbD genes conferred psbA mRNA accumulation but not translation. Overall, our results show that heterologous D1 proteins can be expressed and complement Photosystem II function in green algae, while RNA regulatory elements appear to be very specific and function only from closely related species. Nonetheless, there is great potential for the expression of heterologous photosynthetic coding sequences for studying and modifying photosynthesis in C. reinhardtii chloroplasts.
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Affiliation(s)
- Javier A Gimpel
- San Diego Center for Algae Biotechnology, Division of Biological Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0368, USA
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Kim KS, Kim KS, Park S, Lee S, Kang SB, Lee J, Lee SG, Ryu CM. A novel fluorescent reporter system for monitoring and identifying RNase III activity and its target RNAs. RNA Biol 2012; 9:1167-76. [PMID: 22951591 DOI: 10.4161/rna.21499] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Bacteriophage vectors for achieving single-copy gene expression linked to a colorigenic reporter assay have been used successfully for genetic screening applications. However, the limited number of cloning sites in these vectors, combined with the requirement for lac- strains and the time- and/or media-dependence of the chemical-based colorimetric reaction, have limited the range of applications for these vectors. An alternative approach using a fluorescent reporter gene such as green fluorescent protein (GFP) or GFP derivatives could overcome some of these technical issues and facilitate real-time monitoring of promoter and/or protein activity. Here, we report the development of a novel translational bacteriophage fusion vector encoding enhanced GFP (eGFP) that can be incorporated into the chromosome as a single-copy gene. We identified a Bacillus promoter (BP) that is stably expressed in Escherichia coli and drives ~6-fold more expression of eGFP than the T7 promoter in the absence of inducer. Incorporating this BP and RNase III target signals into a single system enabled clear detection of the absence or downregulation of RNase III activity in vivo, thereby establishing a system for screening and identifying novel RNase III targets in a matter of days. An RNase III target signal identified in this manner was confirmed by post-transcriptional analysis. We anticipate that this novel translational fusion vector will be used extensively to study activity of both interesting RNases and related complex or to identify or validate targets of RNases that are otherwise difficult to study due to their sensitivity to environmental stresses and/or autoregulatory processes.
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Affiliation(s)
- Kwang-Sun Kim
- Systems and Synthetic Biology Research Center; Korea Research Institute of Bioscience & Biotechnology, Yuseong-gu, Daejeon, Korea.
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Baranauskas A, Paliksa S, Alzbutas G, Vaitkevicius M, Lubiene J, Letukiene V, Burinskas S, Sasnauskas G, Skirgaila R. Generation and characterization of new highly thermostable and processive M-MuLV reverse transcriptase variants. Protein Eng Des Sel 2012; 25:657-68. [PMID: 22691702 DOI: 10.1093/protein/gzs034] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In vitro synthesis of cDNA is one of the most important techniques in present molecular biology. Faithful synthesis of long cDNA on highly structured RNA templates requires thermostable and processive reverse transcriptases. In a recent attempt to increase the thermostability of the wt Moloney Murine leukemia virus reverse transcriptase (M-MuLV RT), we have employed the compartmentalized ribosome display (CRD) evolution in vitro technique and identified a large set of previously unknown mutations that enabled cDNA synthesis at elevated temperatures. In this study, we have characterized a group of the M-MuLV RT variants (28 novel amino acid positions, 84 point mutants) carrying the individual mutations. The performance of point mutants (thermal inactivation rate, substrate-binding affinity and processivity) correlated remarkably well with the mutation selection frequency in the CRD experiment. By combining the best-performing mutations D200N, L603W, T330P, L139P and E607K, we have generated highly processive and thermostable multiply-mutated M-MuLV RT variants. The processivity of the best-performing multiple mutant increased to 1500 nt (65-fold improvement in comparison to the wt enzyme), and the maximum temperature of the full-length 7.5-kb cDNA synthesis was raised to 62°C (17° higher in comparison with the wt enzyme).
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Abstract
Cyanobacteria are the only prokaryotes capable of using sunlight as their energy, water as an electron donor, and air as a source of carbon and, for some nitrogen-fixing strains, nitrogen. Compared to algae and plants, cyanobacteria are much easier to genetically engineer, and many of the standard biological parts available for Synthetic Biology applications in Escherichia coli can also be used in cyanobacteria. However, characterization of such parts in cyanobacteria reveals differences in performance when compared to E. coli, emphasizing the importance of detailed characterization in the cellular context of a biological chassis. Furthermore, cyanobacteria possess special characteristics (e.g., multiple copies of their chromosomes, high content of photosynthetically active proteins in the thylakoids, the presence of exopolysaccharides and extracellular glycolipids, and the existence of a circadian rhythm) that have to be taken into account when genetically engineering them. With this chapter, the synthetic biologist is given an overview of existing biological parts, tools and protocols for the genetic engineering, and molecular analysis of cyanobacteria for Synthetic Biology applications.
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