1
|
Selection and Validation of Reliable Reference Genes for qRT-PCR Normalization of Bursaphelenchus xylophilus from Different Temperature Conditions and Developmental Stages. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12062880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is a powerful technique for studying gene expression. The key to quantitative accuracy depends on the stability of the reference genes used for data normalization under different experimental conditions. Pine wood nematode (PWN; Bursaphelenchus xylophilus) is the causal agent of the devastating pine wilt disease (PWD). Extensive and prompt research is needed to understand the molecular mechanism of PWD, but identification of the reference PWN genes for standardized qRT-PCR has not been reported yet. We have analyzed eight candidate reference genes of PWN across different temperature conditions and developmental stages. Delta Ct method, GeNorm, NormFinder, BestKeeper, and RefFinder algorithms were used to evaluate the stability of expression of these genes. Finally, we use arginine kinase gene (AK) in different temperatures and heat shock protein 90 (HSP90) in different developmental stages to confirm the stability of these genes. UBCE and EF1γ were most stable across different temperature treatments, whereas EF1γ and Actin were most stable across different developmental stages. In general, these results indicate that EF1γ is the most stable gene for qRT-PCR under different conditions. The systematic analysis of qRT-PCR reference gene selection will be helpful for future functional analysis and exploration of B. xylophilus genetic resources.
Collapse
|
2
|
Bahaaeldine MA, El Garhy M, Fahmy SR, Mohamed AS. In vitro anti-Toxocara vitulorum effect of silver nanoparticles. J Parasit Dis 2022; 46:409-420. [DOI: 10.1007/s12639-021-01464-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/20/2021] [Indexed: 11/24/2022] Open
|
3
|
The immunogenic maturation of goat monocyte-derived dendritic cells and upregulation of toll-like receptors by five antigens of Haemonchus contortus in-vitro. Res Vet Sci 2021; 136:247-258. [PMID: 33721712 DOI: 10.1016/j.rvsc.2021.03.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 03/01/2021] [Accepted: 03/04/2021] [Indexed: 12/25/2022]
Abstract
Previously, it was found that several proteins of Haemonchus contortus were involved in the stimulation of the host immune system. However, the information about the selection of superlative antigens with immunogenic efficacies on host DCs is lacking. In the current study, the stimulatory effects of five recombinant proteins (elongation factor-1α, arginine kinase, ES-15, ES-24, and ADP-ribosylation factor 1) of H. contortus on the maturation of goat monocyte-derived dendritic cells (md-DCs) were reported. Recombinant proteins were purified separately in E. coli expression and incubated with isolated goat peripheral blood mononuclear cells (PBMC). Immunofluorescence assay (IFA) results confirmed the binding of these molecules to the md-DC's surface as compared to control groups. In the flow cytometry analysis, recombinant proteins induced md-DC stimulation via the up-regulation of the expression of the costimulatory molecule (CD80) and MHC-II. Quantitative RT-PCR data showed a significant increase in the expression of specific genes of the WNT and toll-like receptor (TLR) signaling pathways. The result of ELISA indicated the higher levels of cytokine (IL-10, IL-12, IFN-γ, and TNF-α) secretion in the md-DC compared to the negative (pET-32a His-Tag) and blank (PBS) control groups. The data gives valuable support in the selection of potential antigens for future studies on the immunomodulation of the host against the infection of H. contortus.
Collapse
|
4
|
Yang Z, Huang X, Liao H, Zhang Z, Sun F, Kou S, Bao Z. Structure and functional analysis reveal an important regulated role of arginine kinase in Patinopecten yessoensis under low pH stress. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 222:105452. [PMID: 32092594 DOI: 10.1016/j.aquatox.2020.105452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/11/2020] [Accepted: 02/17/2020] [Indexed: 06/10/2023]
Abstract
Arginine kinase (AK), an important member of the phosphokinase family, is involved in temporal and spatial adenosine triphosphate (ATP) buffering systems. AK plays an important role in physiological function and metabolic regulations, in particular tissues with high and fluctuating energy demands. In present study, four AK genes were firstly identified from Yesso scallop (Patinopecten yessoensis) genome, respectively named PyAK1-4. PyAKs have highly conserved structures with a six-exon/five-exon structure, except for PyAK3. PyAK3 contains an unusual two-domain structure and a "bridge intron" between the two domains, which may originate from gene duplication and subsequent fusion. Phylogenetic analysis showed that all PyAKs belonged to an AK supercluster together with other AK proteins from Mollusca, Platyhelminthes, Arthropoda, and Nematode. A transcriptome database demonstrated that PyAK3 and PyAK4 were the main functional executors with high expression level during larval development and in adult tissues, while PyAK1 and PyAK2 were expressed at a low level. Furthermore, both PyAK2 and PyAK3 showed notably high expression in the male gonad, and PyAK4 was broadly expressed in almost all tissues with the highest level in striated muscle, indicating a tissue-specific expression pattern of PyAKs. In addition, quantitative real-time PCR results demonstrated that the expression of PyAK2, PyAK3 and PyAK4 were significantly upregulated in response to pH stress, especially in an extremely acidifying condition (pH 6.5), revealing the possible involvement of PyAKs in energetic homeostasis during environmental changes. Collectively, a comprehensive analysis of PyAKs was conducted in P. yessoensis. The diversity of PyAKs and their specific expression patterns promote a better understanding of energy metabolism in the growth, development and environmental response of P. yessoensis.
Collapse
Affiliation(s)
- Zujing Yang
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Xiaoting Huang
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
| | - Huan Liao
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China; College of Animal Biotechnology, Jiangxi Agricultural University, Nanchang, China
| | - Zhengrui Zhang
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Fanhua Sun
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Sihua Kou
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Zhenmin Bao
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| |
Collapse
|
5
|
Gu X, Gu J, Ren Y, Zheng Y, Yang G, Zhou X, Xie Y. Evaluation of an Indirect ELISA Using Recombinant Arginine Kinase for Serodiagnosis of Psoroptes ovis var. cuniculi Infestation in Rabbits. Front Vet Sci 2019; 6:411. [PMID: 31824969 PMCID: PMC6879429 DOI: 10.3389/fvets.2019.00411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/05/2019] [Indexed: 11/23/2022] Open
Abstract
Psoroptes ovis var. cuniculi is a common ectoparasite of the wild and domestic rabbits worldwide, which causes significant economic losses in commercial rabbit breeding. In China, the diagnosis of rabbits infested with P. ovis var. cuniculi currently relies on detection of clinical signs and Psoroptes mites in skin scrapings by microscopy examination. However, this method is not very efficient in detection of the low mite loads and/or sub-clinical infections. In the present study, we cloned and expressed an arginine kinase homolog gene from P. ovis var. cuniculi (Poc-AK) and used its recombinant protein rPoc-AK to develop an indirect enzyme-linked immunosorbent assay (iELISA) method for diagnosis of P. ovis var. cuniculi infestation in rabbits. The results showed that the rPoc-AK protein was ~61 kDa and had no signal peptide. The rPoc-AK-based iELISA achieved a 94.4% sensitivity and a 88.2% specificity, and was able to detect P. ovis var. cuniculi infection as early as the 1st week post-infection, prior to the appearance of clinical signs. Further field study showed 24.94% (66.33/266) clinically normal rabbits were seropositive with the highest and lowest seropositive rates for California (35.71%) and Belgian (15.14%), respectively. These results suggested that the rPoc-AK has potential as a diagnostic antigen for early P. ovis var. cuniculi infestation in rabbits.
Collapse
Affiliation(s)
- Xiaobin Gu
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Jiang Gu
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yongjun Ren
- Institute of Veterinary Pharmacology, Sichuan Animal Science Academy, Chengdu, China.,Animal Breeding and Genetics Key Laboratory of Sichuan Province, Sichuan Animal Science Academy, Chengdu, China
| | - Youle Zheng
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Guangyou Yang
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xuan Zhou
- Institute of Animal Genetics and Breeding, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Yue Xie
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| |
Collapse
|
6
|
Petkowski JJ, Bains W, Seager S. Natural Products Containing 'Rare' Organophosphorus Functional Groups. Molecules 2019; 24:E866. [PMID: 30823503 PMCID: PMC6429109 DOI: 10.3390/molecules24050866] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/13/2019] [Accepted: 02/22/2019] [Indexed: 12/25/2022] Open
Abstract
Phosphorous-containing molecules are essential constituents of all living cells. While the phosphate functional group is very common in small molecule natural products, nucleic acids, and as chemical modification in protein and peptides, phosphorous can form P⁻N (phosphoramidate), P⁻S (phosphorothioate), and P⁻C (e.g., phosphonate and phosphinate) linkages. While rare, these moieties play critical roles in many processes and in all forms of life. In this review we thoroughly categorize P⁻N, P⁻S, and P⁻C natural organophosphorus compounds. Information on biological source, biological activity, and biosynthesis is included, if known. This review also summarizes the role of phosphorylation on unusual amino acids in proteins (N- and S-phosphorylation) and reviews the natural phosphorothioate (P⁻S) and phosphoramidate (P⁻N) modifications of DNA and nucleotides with an emphasis on their role in the metabolism of the cell. We challenge the commonly held notion that nonphosphate organophosphorus functional groups are an oddity of biochemistry, with no central role in the metabolism of the cell. We postulate that the extent of utilization of some phosphorus groups by life, especially those containing P⁻N bonds, is likely severely underestimated and has been largely overlooked, mainly due to the technological limitations in their detection and analysis.
Collapse
Affiliation(s)
- Janusz J Petkowski
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Mass. Ave., Cambridge, MA 02139, USA.
| | - William Bains
- Rufus Scientific, 37 The Moor, Melbourn, Royston, Herts SG8 6ED, UK.
| | - Sara Seager
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Mass. Ave., Cambridge, MA 02139, USA.
- Department of Physics, Massachusetts Institute of Technology, 77 Mass. Ave., Cambridge, MA 02139, USA.
- Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Mass. Ave., Cambridge, MA 02139, USA.
| |
Collapse
|
7
|
Zhou L, Chen F, Ye J, Pan H. Selection of Reliable Reference Genes for RT-qPCR Analysis of Bursaphelenchus mucronatus Gene Expression From Different Habitats and Developmental Stages. Front Genet 2018; 9:269. [PMID: 30083182 PMCID: PMC6064934 DOI: 10.3389/fgene.2018.00269] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/02/2018] [Indexed: 12/13/2022] Open
Abstract
Quantitative reverse transcription polymerase chain reaction (RT-qPCR), a sensitive technique for gene expression analysis, depends on the stability of the reference genes used for data normalization under different experimental conditions. Bursaphelenchus mucronatus, a pine-parasitic nematode varying in virulence, is widely distributed in natural pine forests throughout the northern hemisphere, but has not been investigated with respect to the identification of reference genes suitable for the normalization of RT-qPCR data. In the present study, eight candidate reference genes were analyzed in B. mucronatus under different habitat conditions and at different developmental stages. The expression stability of these genes was assessed by geNorm, NormFinder, BestKeeper, delta Cq, and RefFinder algorithms. In general, our results identified encoding beta-tubulin as the most stable gene. Moreover, pairwise analysis showed that three reference genes were sufficient to normalize the gene expression data under each set of conditions, with genes encoding beta-tubulin, 18S ribosomal RNA and ubiquitin-conjugating enzyme being the most suitable reference genes for different habitat conditions, whereas genes encoding beta-tubulin, histone, and 18S ribosomal RNA exhibited the most stable expression at different developmental stages. Validation of the selected reference genes was performed by profiling the expression of the fatty acid- and retinol-binding protein gene in different habitats, and by profiling the expression of the arginine kinase gene at different developmental stages. This first systematic analysis for the selection of suitable reference genes for RT-qPCR in B. mucronatus will facilitate future functional analyses and deep mining of genetic resources in this nematode.
Collapse
Affiliation(s)
| | - Fengmao Chen
- Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
| | - Jianren Ye
- Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
| | | |
Collapse
|
8
|
Ehsan M, Gao W, Gadahi JA, Lu M, Liu X, Wang Y, Yan R, Xu L, Song X, Li X. Arginine kinase from Haemonchus contortus decreased the proliferation and increased the apoptosis of goat PBMCs in vitro. Parasit Vectors 2017. [PMID: 28651566 PMCID: PMC5485575 DOI: 10.1186/s13071-017-2244-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Arginine kinase (AK), an important member of phosphagen kinase family has been extensively studied in various vertebrates and invertebrates. Immunologically, AKs are important constituents of different body parts, involved in various biological and cellular functions, and considered as immune-modulator and effector for pro-inflammatory cytokines. However, immunoregulatory changes of host cells triggered by AK protein of Haemonchus contortus, a parasitic nematode of ruminants, are still unknown. The current study was focused on cloning and characterisation of Hc-AK, and its regulatory effects on cytokines level, cell migration, cell proliferation, nitric oxide production and apoptosis of goat peripheral blood mononuclear cells (PBMCs) were observed. METHODS The full-length sequence of the Hc-AK gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and sub-cloned into the prokaryotic expression vector pET-32a. The biochemical characteristics of recombinant protein Hc-AK, which was purified by affinity chromatography, were performed based on the enzymatic assay. Binding of rHc-AK with PBMCs was confirmed by immunofluorescence assay (IFA). Immunohistochemical analysis was used to detect localisation of Hc-AK within adult worms sections. The immunoregulatory effects of rHc-AK on cytokine secretions, cell proliferation, cell migration, nitric oxide production and apoptosis were determined by co-incubation of rHc-AK with goat PBMCs. RESULTS The full-length ORF (1080 bp) of the Hc-AK gene was successfully cloned, and His-tagged AK protein was expressed in the Escherichia coli strain BL21. The recombinant protein of Hc-AK (rHc-AK) was about 58.5 kDa together with the fused vector protein of 18 kDa. The biochemical assay showed that the protein encoded by the Hc-ak exhibited enzymatic activity. Western blot analysis confirmed that the rHc-AK was recognised by the sera from rat (rat-antiHc-AK). The IFA results showed that rHc-AK could bind on the surface of goat PBMCs. Immunohistochemically, Hc-AK was localised at the inner and outer membrane as well as in the gut region of adult worms. The binding of rHc-AK to host cells increased the levels of IL-4, IL-10, IL-17, IFN-γ, nitric oxide (NO) production and cell apoptosis of goat PBMCs, whereas, TGF-β1 levels, cell proliferation and PBMCs migration were significantly decreased in a dose dependent manner. CONCLUSIONS Our findings suggested that rHc-AK is an important excretory and secretory (ES) protein involved in host immune responses and exhibit distinct immunomodulatory properties during interaction with goat PBMCs.
Collapse
Affiliation(s)
- Muhammad Ehsan
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - WenXiang Gao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Javaid Ali Gadahi
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.,Department of Veterinary Parasitology, Sindh Agriculture University, Tandojam, Pakistan
| | - MingMin Lu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - XinChao Liu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - YuJian Wang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - RuoFeng Yan
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - LiXin Xu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - XiaoKai Song
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - XiangRui Li
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
| |
Collapse
|
9
|
Wickramasinghe S, Yatawara L, Nagataki M, Agatsuma T. Arginine kinase in Toxocara canis: Exon-intron organization, functional analysis of site-directed mutants and evaluation of putative enzyme inhibitors. ASIAN PAC J TROP MED 2016; 9:995-1001. [PMID: 27794395 DOI: 10.1016/j.apjtm.2016.07.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 06/15/2016] [Accepted: 07/15/2016] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVES To determine exon/intron organization of the Toxocara canis (T. canis) AK (TCAK) and to test green and black tea and several other chemicals against the activity of recombinant TCAK in the guanidino-specific region by site-directed mutants. METHODS Amplification of genomic DNA fragments containing introns was carried out by PCRs. The open-reading frame (1200 bp) of TCAK (wild type) was cloned into the BamH1/SalI site of pMAL-c2X. The maltose-binding protein-TCAK fusion protein was expressed in Escherichia coli TB1 cells. The purity of the expressed enzyme was verified by SDS-PAGE. Mutations were introduced into the guanidino-specific region and other areas of pMAL/TCAK by PCR. Enzyme activity was measured with an NADH-linked assay at 25 °C for the forward reaction (phosphagen synthesis). RESULTS Arginine kinase in T. canis has a seven-exon/six-intron gene structure. The lengths of the introns ranged from 542 bp to 2 500 bp. All introns begin with gt and end with ag. Furthermore, we measured the enzyme activity of site-directed mutants of the recombinant TCAK. The Km value of the mutant (Alanine to Serine) decreased indicating a higher affinity for substrate arginine than the wild-type. The Km value of the mutant (Serine to Glycine) increased to 0.19 mM. The Km value (0.19 mM) of the double mutant (Alanine-Serine to Serine-Glycine) was slightly greater than in the wild-type (0.12 mM). In addition, several other chemicals were tested; including plant extract Azadiracta indica (A. indica), an aminoglycoside antibiotic (aminosidine), a citrus flavonoid glycoside (rutin) and a commercially available catechin mixture against TCAK. Green and black tea (1:10 dilution) produced 15% and 25% inhibition of TCAK, respectively. The extract of A. indica produced 5% inhibition of TCAK. Moreover, green and black tea produced a non-competitive type of inhibition and A. indica produced a mixed-type of inhibition on TCAK. CONCLUSIONS Arginine kinase in T. canis has a seven-exon/six-intron gene structure. However, further studies are needed to identify a specific compound within the extract causing the inhibitory effect and also to determine the molecular mechanisms behind inhibition of arginine kinase in T. canis.
Collapse
Affiliation(s)
- Susiji Wickramasinghe
- Department of Parasitology, Faculty of Medicine, University of Peradeniya, Peradeniya 20400, Sri Lanka.
| | - Lalani Yatawara
- Department of Medical Laboratory Sciences, Faculty of Allied Health Sciences, University of Peradeniya, Peradeniya 20400, Sri Lanka
| | - Mitsuru Nagataki
- Department of Environmental Health Sciences, Kochi Medical School, Oko, Nankoku City, Kochi Ken 783-8505, Japan
| | - Takeshi Agatsuma
- Department of Environmental Health Sciences, Kochi Medical School, Oko, Nankoku City, Kochi Ken 783-8505, Japan
| |
Collapse
|
10
|
Qi XL, Su XF, Lu GQ, Liu CX, Liang GM, Cheng HM. The effect of silencing arginine kinase by RNAi on the larval development of Helicoverpa armigera. BULLETIN OF ENTOMOLOGICAL RESEARCH 2015; 105:555-565. [PMID: 26138927 DOI: 10.1017/s0007485315000450] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Arginine kinase (AK) is an important regulation factor of energy metabolism in invertebrate. An arginine kinase gene, named HaAK, was identified to be differentially expressed between Cry1Ac-susceptible (96S) and Cry1Ac-resistant (Bt-R) Helicoverpa armigera larvae using cDNA-amplification fragment length polymorphism analysis. The full-length open reading frame sequence of HaAK gene with 1068 bp was isolated from H. armigera. Quantitative reverse transcription polymerase chain reaction assay revealed that HaAK gene is specifically expressed in multiple tissues and at larval developmental stages. The peak expression level of HaAK was detected in the midgut of the fifth-instar larvae. Moreover, the expression of HaAK was obviously down-regulated in Bt-R larvae. We further constructed a dsRNA vector directly targeting HaAK and employed RNAi technology to control the larvae. The feeding bioassays showed that minute quantities of dsRNA could greatly increase the larval mortality and delay the larval pupation. Silencing of HaAK significantly retarded the larval development, indicating that HaAK is a potential target for RNA interference-based pest management.
Collapse
Affiliation(s)
- X-L Qi
- Biotechnology Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081,China
| | - X-F Su
- Biotechnology Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081,China
| | - G-Q Lu
- Biotechnology Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081,China
| | - C-X Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193,China
| | - G-M Liang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193,China
| | - H-M Cheng
- Biotechnology Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081,China
| |
Collapse
|
11
|
Umair S, Knight JS, Bland RJ, Simpson HV. Molecular and biochemical characterisation of arginine kinases in Haemonchus contortus and Teladorsagia circumcincta. Exp Parasitol 2013; 134:362-7. [PMID: 23583781 DOI: 10.1016/j.exppara.2013.03.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 02/21/2013] [Accepted: 03/17/2013] [Indexed: 12/23/2022]
Abstract
Full length cDNA encoding arginine kinases (AK) were cloned from Teladorsagia circumcincta (TcAK) and Haemonchus contortus (HcAK). The TcAK and HcAK cDNA (1080 bp) encoded 360 amino acid proteins. The predicted amino acid sequence showed 99% similarity with each other and 94% with a Caenorhabditis elegans AK. Soluble N-terminal His-tagged AK proteins were expressed in Escherichia coli strain BL21, purified and characterised. All binding sites were completely conserved in both proteins. The recombinant TcAK and HcAK had very similar kinetic properties: K(m) arginine was 0.35 mM, K(m) ATP was 0.8-0.9 mM and the pH optima were pH 7.5. Arginine analogues strongly inhibited recombinant enzyme activities (up to 80%), whilst other amino acids decreased activities by a maximum of 20%. TcAK and HcAK are potential vaccine candidates because of the strong antigenicity of invertebrate phosphagens and kinases and presence in metabolically active parts of the worm.
Collapse
Affiliation(s)
- S Umair
- Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11-222, Palmerston North, New Zealand.
| | | | | | | |
Collapse
|