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Michael-Pitschaze T, Cohen N, Ofer D, Hoshen Y, Linial M. Detecting anomalous proteins using deep representations. NAR Genom Bioinform 2024; 6:lqae021. [PMID: 38486884 PMCID: PMC10939404 DOI: 10.1093/nargab/lqae021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 11/17/2023] [Accepted: 02/23/2024] [Indexed: 03/17/2024] Open
Abstract
Many advances in biomedicine can be attributed to identifying unusual proteins and genes. Many of these proteins' unique properties were discovered by manual inspection, which is becoming infeasible at the scale of modern protein datasets. Here, we propose to tackle this challenge using anomaly detection methods that automatically identify unexpected properties. We adopt a state-of-the-art anomaly detection paradigm from computer vision, to highlight unusual proteins. We generate meaningful representations without labeled inputs, using pretrained deep neural network models. We apply these protein language models (pLM) to detect anomalies in function, phylogenetic families, and segmentation tasks. We compute protein anomaly scores to highlight human prion-like proteins, distinguish viral proteins from their host proteome, and mark non-classical ion/metal binding proteins and enzymes. Other tasks concern segmentation of protein sequences into folded and unstructured regions. We provide candidates for rare functionality (e.g. prion proteins). Additionally, we show the anomaly score is useful in 3D folding-related segmentation. Our novel method shows improved performance over strong baselines and has objectively high performance across a variety of tasks. We conclude that the combination of pLM and anomaly detection techniques is a valid method for discovering a range of global and local protein characteristics.
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Affiliation(s)
- Tomer Michael-Pitschaze
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Niv Cohen
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Dan Ofer
- Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yedid Hoshen
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Michal Linial
- Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
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2
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Abstract
Antibiotic resistance constitutes a global threat and could lead to a future pandemic. One strategy is to develop a new generation of antimicrobials. Naturally occurring antimicrobial peptides (AMPs) are recognized templates and some are already in clinical use. To accelerate the discovery of new antibiotics, it is useful to predict novel AMPs from the sequenced genomes of various organisms. The antimicrobial peptide database (APD) provided the first empirical peptide prediction program. It also facilitated the testing of the first machine-learning algorithms. This chapter provides an overview of machine-learning predictions of AMPs. Most of the predictors, such as AntiBP, CAMP, and iAMPpred, involve a single-label prediction of antimicrobial activity. This type of prediction has been expanded to antifungal, antiviral, antibiofilm, anti-TB, hemolytic, and anti-inflammatory peptides. The multiple functional roles of AMPs annotated in the APD also enabled multi-label predictions (iAMP-2L, MLAMP, and AMAP), which include antibacterial, antiviral, antifungal, antiparasitic, antibiofilm, anticancer, anti-HIV, antimalarial, insecticidal, antioxidant, chemotactic, spermicidal activities, and protease inhibiting activities. Also considered in predictions are peptide posttranslational modification, 3D structure, and microbial species-specific information. We compare important amino acids of AMPs implied from machine learning with the frequently occurring residues of the major classes of natural peptides. Finally, we discuss advances, limitations, and future directions of machine-learning predictions of antimicrobial peptides. Ultimately, we may assemble a pipeline of such predictions beyond antimicrobial activity to accelerate the discovery of novel AMP-based antimicrobials.
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Affiliation(s)
- Guangshun Wang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA;,Corresponding to: Dr. Monique van Hoek: ; Dr. Iosif Vaisman: ; Dr. Guangshun Wang:
| | - Iosif I. Vaisman
- School of Systems Biology, George Mason University, 10920 George Mason Circle, Manassas, VA, 20110, USA.,Corresponding to: Dr. Monique van Hoek: ; Dr. Iosif Vaisman: ; Dr. Guangshun Wang:
| | - Monique L. van Hoek
- School of Systems Biology, George Mason University, 10920 George Mason Circle, Manassas, VA, 20110, USA.,Corresponding to: Dr. Monique van Hoek: ; Dr. Iosif Vaisman: ; Dr. Guangshun Wang:
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3
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Hu X, Li R, Chen J, Mu Q. Synthesis and anti‐hepatocellular carcinoma activity
in vitro
of cyclic peptide
GG
‐8‐6 analogues. J Heterocycl Chem 2021. [DOI: 10.1002/jhet.4397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xiao‐Zhi Hu
- School of Pharmacy Fudan University Shanghai China
| | | | - Jie‐Tao Chen
- School of Pharmacy Fudan University Shanghai China
| | - Qing Mu
- School of Pharmacy Fudan University Shanghai China
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4
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Mining the Royal Jelly Proteins: Combinatorial Hexapeptide Ligand Library Significantly Improves the MS-Based Proteomic Identification in Complex Biological Samples. MOLECULES (BASEL, SWITZERLAND) 2021; 26:molecules26092762. [PMID: 34067143 PMCID: PMC8125745 DOI: 10.3390/molecules26092762] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 12/18/2022]
Abstract
Royal jelly (RJ) is a complex, creamy secretion produced by the glands of worker bees. Due to its health-promoting properties, it is used by humans as a dietary supplement. However, RJ compounds are not fully characterized yet. Hence, in this research, we aimed to broaden the knowledge of the proteomic composition of fresh RJ. Water extracts of the samples were pre-treated using combinatorial hexapeptide ligand libraries (ProteoMinerTM kit), trypsin-digested, and analyzed by a nanoLC-MALDI-TOF/TOF MS system. To check the ProteoMinerTM performance in the MS-based protein identification, we also examined RJ extracts that were not prepared with the ProteoMinerTM kit. We identified a total of 86 proteins taxonomically classified to Apis spp. (bees). Among them, 74 proteins were detected in RJ extracts pre-treated with ProteoMinerTM kit, and only 50 proteins were found in extracts non-enriched with this technique. Ten of the identified features were hypothetical proteins whose existence has been predicted, but any experimental evidence proves their in vivo expression. Additionally, we detected four uncharacterized proteins of unknown functions. The results of this research indicate that the ProteoMinerTM strategy improves proteomic identification in complex biological samples. Broadening the knowledge of RJ composition may contribute to the development of standards and regulations, enhancing the quality of RJ, and consequently, the safety of its supplementation.
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5
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Toxin-like neuropeptides in the sea anemone Nematostella unravel recruitment from the nervous system to venom. Proc Natl Acad Sci U S A 2020; 117:27481-27492. [PMID: 33060291 DOI: 10.1073/pnas.2011120117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The sea anemone Nematostella vectensis (Anthozoa, Cnidaria) is a powerful model for characterizing the evolution of genes functioning in venom and nervous systems. Although venom has evolved independently numerous times in animals, the evolutionary origin of many toxins remains unknown. In this work, we pinpoint an ancestral gene giving rise to a new toxin and functionally characterize both genes in the same species. Thus, we report a case of protein recruitment from the cnidarian nervous to venom system. The ShK-like1 peptide has a ShKT cysteine motif, is lethal for fish larvae and packaged into nematocysts, the cnidarian venom-producing stinging capsules. Thus, ShK-like1 is a toxic venom component. Its paralog, ShK-like2, is a neuropeptide localized to neurons and is involved in development. Both peptides exhibit similarities in their functional activities: They provoke contraction in Nematostella polyps and are toxic to fish. Because ShK-like2 but not ShK-like1 is conserved throughout sea anemone phylogeny, we conclude that the two paralogs originated due to a Nematostella-specific duplication of a ShK-like2 ancestor, a neuropeptide-encoding gene, followed by diversification and partial functional specialization. ShK-like2 is represented by two gene isoforms controlled by alternative promoters conferring regulatory flexibility throughout development. Additionally, we characterized the expression patterns of four other peptides with structural similarities to studied venom components and revealed their unexpected neuronal localization. Thus, we employed genomics, transcriptomics, and functional approaches to reveal one venom component, five neuropeptides with two different cysteine motifs, and an evolutionary pathway from nervous to venom system in Cnidaria.
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6
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Molecular Docking Studies of a Cyclic Octapeptide-Cyclosaplin from Sandalwood. Biomolecules 2019; 9:biom9110740. [PMID: 31731771 PMCID: PMC6920920 DOI: 10.3390/biom9110740] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 11/12/2019] [Indexed: 12/11/2022] Open
Abstract
Natural products from plants, such as chemopreventive agents, attract huge attention because of their low toxicity and high specificity. The rational drug design in combination with structure-based modeling and rapid screening methods offer significant potential for identifying and developing lead anticancer molecules. Thus, the molecular docking method plays an important role in screening a large set of molecules based on their free binding energies and proposes structural hypotheses of how the molecules can inhibit the target. Several peptide-based therapeutics have been developed to combat several health disorders, including cancers, metabolic disorders, heart-related diseases, and infectious diseases. Despite the discovery of hundreds of such therapeutic peptides however, only few peptide-based drugs have made it to the market. Moreover, the in silico activities of cyclic peptides towards molecular targets, such as protein kinases, proteases, and apoptosis related proteins have not been extensively investigated. In this study, we explored the in silico kinase and protease inhibitor potentials of cyclosaplin, and studied the interactions of cyclosaplin with other apoptosis-related proteins. Previously, the structure of cyclosaplin was elucidated by molecular modeling associated with dynamics that were used in the current study as well. Docking studies showed strong affinity of cyclosaplin towards cancer-related proteins. The binding affinity closer to 10 kcal/mol indicated efficient binding. Cyclosaplin showed strong binding affinities towards protein kinases such as EGFR, VEGFR2, PKB, and p38, indicating its potential role in protein kinase inhibition. Moreover, it displayed strong binding affinity to apoptosis-related proteins and revealed the possible role of cyclosaplin in apoptotic cell death. The protein–ligand interactions using LigPlot displayed some similar interactions between cyclosaplin and peptide-based ligands, especially in case of protein kinases and a few apoptosis related proteins. Thus, the in silico analyses gave the insights of cyclosaplin being a potential apoptosis inducer and protein kinase inhibitor.
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7
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Macrander J, Panda J, Janies D, Daly M, Reitzel AM. Venomix: a simple bioinformatic pipeline for identifying and characterizing toxin gene candidates from transcriptomic data. PeerJ 2018; 6:e5361. [PMID: 30083468 PMCID: PMC6074769 DOI: 10.7717/peerj.5361] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/09/2018] [Indexed: 12/12/2022] Open
Abstract
The advent of next-generation sequencing has resulted in transcriptome-based approaches to investigate functionally significant biological components in a variety of non-model organism. This has resulted in the area of “venomics”: a rapidly growing field using combined transcriptomic and proteomic datasets to characterize toxin diversity in a variety of venomous taxa. Ultimately, the transcriptomic portion of these analyses follows very similar pathways after transcriptome assembly often including candidate toxin identification using BLAST, expression level screening, protein sequence alignment, gene tree reconstruction, and characterization of potential toxin function. Here we describe the Python package Venomix, which streamlines these processes using common bioinformatic tools along with ToxProt, a publicly available annotated database comprised of characterized venom proteins. In this study, we use the Venomix pipeline to characterize candidate venom diversity in four phylogenetically distinct organisms, a cone snail (Conidae; Conus sponsalis), a snake (Viperidae; Echis coloratus), an ant (Formicidae; Tetramorium bicarinatum), and a scorpion (Scorpionidae; Urodacus yaschenkoi). Data on these organisms were sampled from public databases, with each original analysis using different approaches for transcriptome assembly, toxin identification, or gene expression quantification. Venomix recovered numerically more candidate toxin transcripts for three of the four transcriptomes than the original analyses and identified new toxin candidates. In summary, we show that the Venomix package is a useful tool to identify and characterize the diversity of toxin-like transcripts derived from transcriptomic datasets. Venomix is available at: https://bitbucket.org/JasonMacrander/Venomix/.
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Affiliation(s)
- Jason Macrander
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC, United States of America.,Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH, United States of America
| | - Jyothirmayi Panda
- College of Computing and Informatics, University of North Carolina at Charlotte, Charlotte, NC, United States of America
| | - Daniel Janies
- College of Computing and Informatics, University of North Carolina at Charlotte, Charlotte, NC, United States of America.,Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC, United States of America
| | - Marymegan Daly
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH, United States of America
| | - Adam M Reitzel
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC, United States of America
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8
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Chen JT, Ma R, Sun SC, Zhu XF, Xu XL, Mu Q. Synthesis and biological evaluation of cyclopeptide GG-8-6 and its analogues as anti-hepatocellular carcinoma agents. Bioorg Med Chem 2017; 26:609-622. [PMID: 29310863 DOI: 10.1016/j.bmc.2017.12.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 12/16/2017] [Accepted: 12/19/2017] [Indexed: 10/18/2022]
Abstract
GG-8-6, cyclo-(Val-Leu-Pro-Ile-Leu-Leu-Leu-Val-Leu, compound 1), and its twelve analogues (compound 2-13) were synthesized based on the lead compound Grifficyclocin B, a cyclic peptide with anti-tumor activity which was isolated from the plants of Goniothalamus species (Annonaceae). The bioassay results showed that these synthetic cyclopeptides exhibited different extent of cytotoxicity against human hepatocellular carcinoma cell lines. Among them, GG-8-6 (1) was the most active compound with IC50 values of 6.38 μM and 12.22 μM against SMMC-7721 and HepG2, respectively. Further studies on the mechanism demonstrated that GG-8-6 (1) could induce apoptosis and G2/M arrest of HCC cells, and the activation of caspase pathways was probably involved. In vivo anti-tumor experiments showed that GG-8-6 (1) could significantly inhibit the growth of tumor in the mouse xenograft tumor model. At the dose of 40 mg/kg, the inhibition ratio was 67.9% without weight loss. Our results suggested that GG-8-6 (1), a new cyclic peptide, might be a potential candidate for developing new anti-HCC drug in the coming future.
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Affiliation(s)
- Jie-Tao Chen
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Ru Ma
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Shi-Chang Sun
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Xiao-Feng Zhu
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Xiao-Li Xu
- Hospital Fudan University, Shanghai 201203, China
| | - Qing Mu
- School of Pharmacy, Fudan University, Shanghai 201203, China.
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9
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Linial M, Rappoport N, Ofer D. Overlooked Short Toxin-Like Proteins: A Shortcut to Drug Design. Toxins (Basel) 2017; 9:E350. [PMID: 29109389 PMCID: PMC5705965 DOI: 10.3390/toxins9110350] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 10/22/2017] [Accepted: 10/25/2017] [Indexed: 12/22/2022] Open
Abstract
Short stable peptides have huge potential for novel therapies and biosimilars. Cysteine-rich short proteins are characterized by multiple disulfide bridges in a compact structure. Many of these metazoan proteins are processed, folded, and secreted as soluble stable folds. These properties are shared by both marine and terrestrial animal toxins. These stable short proteins are promising sources for new drug development. We developed ClanTox (classifier of animal toxins) to identify toxin-like proteins (TOLIPs) using machine learning models trained on a large-scale proteomic database. Insects proteomes provide a rich source for protein innovations. Therefore, we seek overlooked toxin-like proteins from insects (coined iTOLIPs). Out of 4180 short (<75 amino acids) secreted proteins, 379 were predicted as iTOLIPs with high confidence, with as many as 30% of the genes marked as uncharacterized. Based on bioinformatics, structure modeling, and data-mining methods, we found that the most significant group of predicted iTOLIPs carry antimicrobial activity. Among the top predicted sequences were 120 termicin genes from termites with antifungal properties. Structural variations of insect antimicrobial peptides illustrate the similarity to a short version of the defensin fold with antifungal specificity. We also identified 9 proteins that strongly resemble ion channel inhibitors from scorpion and conus toxins. Furthermore, we assigned functional fold to numerous uncharacterized iTOLIPs. We conclude that a systematic approach for finding iTOLIPs provides a rich source of peptides for drug design and innovative therapeutic discoveries.
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Affiliation(s)
- Michal Linial
- Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| | - Nadav Rappoport
- Institute for Computational Health Sciences, UCSF, San Francisco, CA 94158, USA.
| | - Dan Ofer
- Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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10
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Wang M, Li L, Guo Q, Zhang S, Ji D, Li H. Identification and expression of a new Ly6 gene cluster in zebrafish Danio rerio, with implications of being involved in embryonic immunity. FISH & SHELLFISH IMMUNOLOGY 2016; 54:230-240. [PMID: 27071517 DOI: 10.1016/j.fsi.2016.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/29/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
Lymphocyte antigen-6 (Ly6) superfamily is a large family of proteins and characterized by precisely spaced cysteine motifs, termed the three-finger fold. To date, a large number of members of the Ly6/uPAR family were identified among many species. In this study, we first report the identification and characterization of the secreted Ly2.1-3 proteins on the chromosome 2 in zebrafish and determine the expression pattern. Ly2.1-3 all possess a conserved LU domain and adopt similar three-finger structure with human CD59, SLURP1 and other Ly6 family members. Ly2.1-3 cluster on chromosome 2 and share high homology, possibly originated from chromosomal gene duplication. Ly2.1-3 exhibit distinct expression pattern in the endoderm, they were found abundantly and specifically in the digestive tract, liver and pancreas respectively. The differential expression pattern may suggest Ly2.1-3 acquire new function during gene duplication. The expression level of Ly2.1-3 were up-regulating challenged with LPS indicated that they have a role in innate immune responses of the digestive system during endotoxin challenge in early stage.
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Affiliation(s)
- Man Wang
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Lingyi Li
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Quanyang Guo
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Shicui Zhang
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Dongrui Ji
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
| | - Hongyan Li
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
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11
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Goyffon M, Saul F, Faure G. [Relationships between venomous function and innate immune function]. Biol Aujourdhui 2016; 209:195-210. [PMID: 26820828 DOI: 10.1051/jbio/2015018] [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: 08/21/2015] [Indexed: 06/05/2023]
Abstract
Venomous function is investigated in relation to innate immune function in two cases selected from scorpion venom and serpent venom. In the first case, structural analysis of scorpion toxins and defensins reveals a close interrelation between both functions (toxic and innate immune system function). In the second case, structural and functional studies of natural inhibitors of toxic snake venom phospholipases A2 reveal homology with components of the innate immune system, leading to a similar conclusion. Although there is a clear functional distinction between neurotoxins, which act by targeting membrane ion channels, and the circulating defensins which protect the organism from pathogens, the scorpion short toxins and defensins share a common protein folding scaffold with a conserved cysteine-stabilized alpha-beta motif of three disulfide bridges linking a short alpha helix and an antiparallel beta sheet. Genomic analysis suggests that these proteins share a common ancestor (long venom toxins were separated from an early gene family which gave rise to separate short toxin and defensin families). Furthermore, a scorpion toxin has been experimentally synthetized from an insect defensin, and an antibacterial scorpion peptide, androctonin (whose structure is similar to that of a cone snail venom toxin), was shown to have a similar high affinity for the postsynaptic acetylcholine receptor of Torpedo sp. Natural inhibitors of phospholipase A2 found in the blood of snakes are associated with the resistance of venomous snakes to their own highly neurotoxic venom proteins. Three classes of phospholipases A2 inhibitors (PLI-α, PLI-β, PLI-γ) have been identified. These inhibitors display diverse structural motifs related to innate immune proteins including carbohydrate recognition domains (CRD), leucine rich repeat domains (found in Toll-like receptors) and three finger domains, which clearly differentiate them from components of the adaptive immune system. Thus, in structure, function and phylogeny, venomous function in both vertebrates and invertebrates are clearly interrelated with innate immune function.
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Affiliation(s)
- Max Goyffon
- UMR CNRS 7245, Département RDDM, Muséum national d'Histoire naturelle, 57 rue Cuvier, 75005 Paris, France
| | - Frederick Saul
- Institut Pasteur, Plate-forme de Cristallographie, CNRS-UMR 3528, 25 rue du Docteur Roux, 75015 Paris, France
| | - Grazyna Faure
- Institut Pasteur, Unité Récepteurs-Canaux, CNRS-UMR 3571, 25 rue du Docteur Roux, 75015 Paris, France
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12
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The Little Known Universe of Short Proteins in Insects: A Machine Learning Approach. SHORT VIEWS ON INSECT GENOMICS AND PROTEOMICS 2015. [DOI: 10.1007/978-3-319-24235-4_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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13
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Haney RA, Ayoub NA, Clarke TH, Hayashi CY, Garb JE. Dramatic expansion of the black widow toxin arsenal uncovered by multi-tissue transcriptomics and venom proteomics. BMC Genomics 2014; 15:366. [PMID: 24916504 PMCID: PMC4058007 DOI: 10.1186/1471-2164-15-366] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 05/08/2014] [Indexed: 12/22/2022] Open
Abstract
Background Animal venoms attract enormous interest given their potential for pharmacological discovery and understanding the evolution of natural chemistries. Next-generation transcriptomics and proteomics provide unparalleled, but underexploited, capabilities for venom characterization. We combined multi-tissue RNA-Seq with mass spectrometry and bioinformatic analyses to determine venom gland specific transcripts and venom proteins from the Western black widow spider (Latrodectus hesperus) and investigated their evolution. Results We estimated expression of 97,217 L. hesperus transcripts in venom glands relative to silk and cephalothorax tissues. We identified 695 venom gland specific transcripts (VSTs), many of which BLAST and GO term analyses indicate may function as toxins or their delivery agents. ~38% of VSTs had BLAST hits, including latrotoxins, inhibitor cystine knot toxins, CRISPs, hyaluronidases, chitinase, and proteases, and 59% of VSTs had predicted protein domains. Latrotoxins are venom toxins that cause massive neurotransmitter release from vertebrate or invertebrate neurons. We discovered ≥ 20 divergent latrotoxin paralogs expressed in L. hesperus venom glands, significantly increasing this biomedically important family. Mass spectrometry of L. hesperus venom identified 49 proteins from VSTs, 24 of which BLAST to toxins. Phylogenetic analyses showed venom gland specific gene family expansions and shifts in tissue expression. Conclusions Quantitative expression analyses comparing multiple tissues are necessary to identify venom gland specific transcripts. We present a black widow venom specific exome that uncovers a trove of diverse toxins and associated proteins, suggesting a dynamic evolutionary history. This justifies a reevaluation of the functional activities of black widow venom in light of its emerging complexity. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-366) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | - Jessica E Garb
- Department of Biological Sciences, University of Massachusetts, Lowell, MA 01854, USA.
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14
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Bloch G, Cohen M. The expression and phylogenetics of the Inhibitor Cysteine Knot peptide OCLP1 in the honey bee Apis mellifera. JOURNAL OF INSECT PHYSIOLOGY 2014; 65:1-8. [PMID: 24721445 DOI: 10.1016/j.jinsphys.2014.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/27/2014] [Accepted: 04/02/2014] [Indexed: 06/03/2023]
Abstract
Small cysteine-rich peptides have diverse functions in insects including antimicrobial defense, phenoloxidase activity regulation, and toxic inhibition of ion channels of prey or predator. We combined bioinformatics and measurements of transcript abundance to start characterizing AmOCLP1, a recently discovered Inhibitor Cysteine Knot peptide in the honey bee Apis mellifera. We found that the genomes of ants, bees, and the wasp Nasonia vitripennis encode orthologous sequences indicating that OCLP1 is a conserved peptide and not unique to the honey bee. Search of available EST libraries and quantitative real time PCR analyses indicate that the transcript of AmOCLP1 is ubiquitous with expression in life stages ranging from embryos to adults and in all tested tissues. In worker honey bees AmOCLP1 expression was not associated with age or task and did not show clear enrichment in any of the tested tissues. There was however a consistent trend toward higher transcript levels in the abdomen of foragers relative to levels in the head or thorax, and compared to levels in the abdomen of younger worker bees. By contrast, in drones AmOCLP1 transcript levels appeared higher in the head relative to the abdomen. Finer analyses of the head and abdomen indicated that the AmOCLP1 transcript is not enriched in the stinger and the associated venom sac or in cephalic exocrine glands. The evolutionary conservation in the Hymenoptera, the ubiquitous expression, and the lack of enrichment in the venom gland, stinger, exocrine glands, and the brain are not consistent with the hypotheses that OCLP1 is a secreted honeybee toxin or an endotoxin acting in the central nervous system. Rather we hypothesize that OCLP1 is a conserved antimicrobial or phenoloxidase inhibitor peptide.
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Affiliation(s)
- Guy Bloch
- Department of Ecology, Evolution, and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| | - Mira Cohen
- Department of Ecology, Evolution, and Behavior, The A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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15
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Mishra A, Gauri SS, Mukhopadhyay SK, Chatterjee S, Das SS, Mandal SM, Dey S. Identification and structural characterization of a new pro-apoptotic cyclic octapeptide cyclosaplin from somatic seedlings of Santalum album L. Peptides 2014; 54:148-58. [PMID: 24503375 DOI: 10.1016/j.peptides.2014.01.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 01/27/2014] [Accepted: 01/27/2014] [Indexed: 11/30/2022]
Abstract
Small cyclic peptides exhibiting potent biological activity have great potential for anticancer therapy. An antiproliferative cyclic octapeptide, cyclosaplin was purified from somatic seedlings of Santalum album L. (sandalwood) using gel filtration and RP-HPLC separation process. The molecular mass of purified peptide was found to be 858 Da and the sequence was determined by MALDI-ToF-PSD-MS as 'RLGDGCTR' (cyclic). The cytotoxic activity of the peptide was tested against human breast cancer (MDA-MB-231) cell line in a dose and time-dependent manner. The purified peptide exhibited significant antiproliferative activity with an IC50 2.06 μg/mL. In a mechanistic approach, apoptosis was observed in differential microscopic studies for peptide treated MDA-MB-231 cells, which was further confirmed by mitochondrial membrane potential, DNA fragmentation assay, cell cycle analysis and caspase 3 activities. The modeling and docking experiments revealed strong affinity (kcal/mol) of peptide toward EGFR and procaspase 3. The co-localization studies revealed that the peptide sensitizes MDA-MB-231 cells by possibly binding to EGFR and induces apoptosis. This unique cyclic octapeptide revealed to be a favorable candidate for development of anticancer agents.
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Affiliation(s)
- Abheepsa Mishra
- Plant Biotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Samiran S Gauri
- Plant Biotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Sourav K Mukhopadhyay
- Plant Biotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Soumya Chatterjee
- Plant Biotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Shibendu S Das
- Plant Biotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Santi M Mandal
- Central Research Facility, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Satyahari Dey
- Plant Biotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
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Tirosh Y, Ofer D, Eliyahu T, Linial M. Short toxin-like proteins attack the defense line of innate immunity. Toxins (Basel) 2013; 5:1314-31. [PMID: 23881252 PMCID: PMC3737499 DOI: 10.3390/toxins5071314] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 01/30/2023] Open
Abstract
ClanTox (classifier of animal toxins) was developed for identifying toxin-like candidates from complete proteomes. Searching mammalian proteomes for short toxin-like proteins (coined TOLIPs) revealed a number of overlooked secreted short proteins with an abundance of cysteines throughout their sequences. We applied bioinformatics and data-mining methods to infer the function of several top predicted candidates. We focused on cysteine-rich peptides that adopt the fold of the three-finger proteins (TFPs). We identified a cluster of duplicated genes that share a structural similarity with elapid neurotoxins, such as α-bungarotoxin. In the murine proteome, there are about 60 such proteins that belong to the Ly6/uPAR family. These proteins are secreted or anchored to the cell membrane. Ly6/uPAR proteins are associated with a rich repertoire of functions, including binding to receptors and adhesion. Ly6/uPAR proteins modulate cell signaling in the context of brain functions and cells of the innate immune system. We postulate that TOLIPs, as modulators of cell signaling, may be associated with pathologies and cellular imbalance. We show that proteins of the Ly6/uPAR family are associated with cancer diagnosis and malfunction of the immune system.
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Affiliation(s)
- Yitshak Tirosh
- Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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17
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Abstract
Cnidaria is a rich phylum that includes thousands of marine species. In this study, we focused on Anthozoa and Hydrozoa that are represented by the Nematostella vectensis (Sea anemone) and Hydra magnipapillata genomes. We present a method for ranking the toxin-like candidates from complete proteomes of Cnidaria. Toxin-like functions were revealed using ClanTox, a statistical machine-learning predictor trained on ion channel inhibitors from venomous animals. Fundamental features that were emphasized in training ClanTox include cysteines and their spacing along the sequences. Among the 83,000 proteins derived from Cnidaria representatives, we found 170 candidates that fulfill the properties of toxin-like-proteins, the vast majority of which were previously unrecognized as toxins. An additional 394 short proteins exhibit characteristics of toxin-like proteins at a moderate degree of confidence. Remarkably, only 11% of the predicted toxin-like proteins were previously classified as toxins. Based on our prediction methodology and manual annotation, we inferred functions for over 400 of these proteins. Such functions include protease inhibitors, membrane pore formation, ion channel blockers and metal binding proteins. Many of the proteins belong to small families of paralogs. We conclude that the evolutionary expansion of toxin-like proteins in Cnidaria contributes to their fitness in the complex environment of the aquatic ecosystem.
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Affiliation(s)
- Yitshak Tirosh
- Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel; (Y.T.); (M.A.)
| | - Itai Linial
- The Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel;
| | - Manor Askenazi
- Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel; (Y.T.); (M.A.)
| | - Michal Linial
- Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel; (Y.T.); (M.A.)
- Author to whom correspondence should be addressed; ; Tel.: +972-2-658-5425; Fax: +972-2-658-6448
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18
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Gätschenberger H, Gimple O, Tautz J, Beier H. Honey bee drones maintain humoral immune competence throughout all life stages in the absence of vitellogenin production. ACTA ACUST UNITED AC 2012; 215:1313-22. [PMID: 22442369 DOI: 10.1242/jeb.065276] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Drones are haploid male individuals whose major social function in honey bee colonies is to produce sperm and mate with a queen. In spite of their limited tasks, the vitality of drones is of utmost importance for the next generation. The immune competence of drones - as compared to worker bees - is largely unexplored. Hence, we studied humoral and cellular immune reactions of in vitro reared drone larvae and adult drones of different age upon artificial bacterial infection. Haemolymph samples were collected after aseptic and septic injury and subsequently employed for (1) the identification of immune-responsive peptides and/or proteins by qualitative proteomic analyses in combination with mass spectrometry and (2) the detection of antimicrobial activity by inhibition-zone assays. Drone larvae and adult drones responded with a strong humoral immune reaction upon bacterial challenge, as validated by the expression of small antimicrobial peptides. Young adult drones exhibited a broader spectrum of defence reactions than drone larvae. Distinct polypeptides including peptidoglycan recognition protein-S2 and lysozyme 2 were upregulated in immunized adult drones. Moreover, a pronounced nodulation reaction was observed in young drones upon bacterial challenge. Prophenoloxidase zymogen is present at an almost constant level in non-infected adult drones throughout the entire lifespan. All observed immune reactions in drones were expressed in the absence of significant amounts of vitellogenin. We conclude that drones - like worker bees - have the potential to activate multiple elements of the innate immune response.
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Affiliation(s)
- Heike Gätschenberger
- BEEgroup, Biocentre, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany
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19
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Tirosh Y, Morpurgo N, Cohen M, Linial M, Bloch G. Raalin, a transcript enriched in the honey bee brain, is a remnant of genomic rearrangement in Hymenoptera. INSECT MOLECULAR BIOLOGY 2012; 21:305-318. [PMID: 22404450 DOI: 10.1111/j.1365-2583.2012.01138.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We identified a predicted compact cysteine-rich sequence in the honey bee genome that we called 'Raalin'. Raalin transcripts are enriched in the brain of adult honey bee workers and drones, with only minimum expression in other tissues or in pre-adult stages. Open-reading frame (ORF) homologues of Raalin were identified in the transcriptomes of fruit flies, mosquitoes and moths. The Raalin-like gene from Drosophila melanogaster encodes for a short secreted protein that is maximally expressed in the adult brain with negligible expression in other tissues or pre-imaginal stages. Raalin-like sequences have also been found in the recently sequenced genomes of six ant species, but not in the jewel wasp Nasonia vitripennis. As in the honey bee, the Raalin-like sequences of ants do not have an ORF. A comparison of the genome region containing Raalin in the genomes of bees, ants and the wasp provides evolutionary support for an extensive genome rearrangement in this sequence. Our analyses identify a new family of ancient cysteine-rich short sequences in insects in which insertions and genome rearrangements may have disrupted this locus in the branch leading to the Hymenoptera. The regulated expression of this transcript suggests that it has a brain-specific function.
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Affiliation(s)
- Y Tirosh
- Department of Biological Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
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20
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Rajesh A, Yenugu S. Genomic organization, tissue distribution and functional characterization of the rat Pate gene cluster. PLoS One 2012; 7:e32633. [PMID: 22479333 PMCID: PMC3316536 DOI: 10.1371/journal.pone.0032633] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 01/28/2012] [Indexed: 12/31/2022] Open
Abstract
The cysteine rich prostate and testis expressed (Pate) proteins identified till date are thought to resemble the three fingered protein/urokinase-type plasminogen activator receptor proteins. In this study, for the first time, we report the identification, cloning and characterization of rat Pate gene cluster and also determine the expression pattern. The rat Pate genes are clustered on chromosome 8 and their predicted proteins retained the ten cysteine signature characteristic to TFP/Ly-6 protein family. PATE and PATE-F three dimensional protein structure was found to be similar to that of the toxin bucandin. Though Pate gene expression is thought to be prostate and testis specific, we observed that rat Pate genes are also expressed in seminal vesicle and epididymis and in tissues beyond the male reproductive tract. In the developing rats (20-60 day old), expression of Pate genes seem to be androgen dependent in the epididymis and testis. In the adult rat, androgen ablation resulted in down regulation of the majority of Pate genes in the epididymides. PATE and PATE-F proteins were found to be expressed abundantly in the male reproductive tract of rats and on the sperm. Recombinant PATE protein exhibited potent antibacterial activity, whereas PATE-F did not exhibit any antibacterial activity. Pate expression was induced in the epididymides when challenged with LPS. Based on our results, we conclude that rat PATE proteins may contribute to the reproductive and defense functions.
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Affiliation(s)
| | - Suresh Yenugu
- Department of Animal Sciences, University of Hyderabad, Hyderabad, India
- * E-mail:
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21
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Caers J, Verlinden H, Zels S, Vandersmissen HP, Vuerinckx K, Schoofs L. More than two decades of research on insect neuropeptide GPCRs: an overview. Front Endocrinol (Lausanne) 2012; 3:151. [PMID: 23226142 PMCID: PMC3510462 DOI: 10.3389/fendo.2012.00151] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 11/14/2012] [Indexed: 11/30/2022] Open
Abstract
This review focuses on the state of the art on neuropeptide receptors in insects. Most of these receptors are G protein-coupled receptors (GPCRs) and are involved in the regulation of virtually all physiological processes during an insect's life. More than 20 years ago a milestone in invertebrate endocrinology was achieved with the characterization of the first insect neuropeptide receptor, i.e., the Drosophila tachykinin-like receptor. However, it took until the release of the Drosophila genome in 2000 that research on neuropeptide receptors boosted. In the last decade a plethora of genomic information of other insect species also became available, leading to a better insight in the functions and evolution of the neuropeptide signaling systems and their intracellular pathways. It became clear that some of these systems are conserved among all insect species, indicating that they fulfill crucial roles in their physiological processes. Meanwhile, other signaling systems seem to be lost in several insect orders or species, suggesting that their actions were superfluous in those insects, or that other neuropeptides have taken over their functions. It is striking that the deorphanization of neuropeptide GPCRs gets much attention, but the subsequent unraveling of the intracellular pathways they elicit, or their physiological functions are often hardly examined. Especially in insects besides Drosophila this information is scarce if not absent. And although great progress made in characterizing neuropeptide signaling systems, even in Drosophila several predicted neuropeptide receptors remain orphan, awaiting for their endogenous ligand to be determined. The present review gives a précis of the insect neuropeptide receptor research of the last two decades. But it has to be emphasized that the work done so far is only the tip of the iceberg and our comprehensive understanding of these important signaling systems will still increase substantially in the coming years.
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Affiliation(s)
| | | | | | | | | | - Liliane Schoofs
- *Correspondence: Liliane Schoofs, Department of Biology, Research Group of Functional Genomics and Proteomics, Naamsestraat 59, KU Leuven, 3000 Leuven, Belgium. e-mail:
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22
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Ida T, Takahashi T, Tominaga H, Sato T, Kume K, Yoshizawa-Kumagaye K, Nishio H, Kato J, Murakami N, Miyazato M, Kangawa K, Kojima M. Identification of the endogenous cysteine-rich peptide trissin, a ligand for an orphan G protein-coupled receptor in Drosophila. Biochem Biophys Res Commun 2011; 414:44-8. [DOI: 10.1016/j.bbrc.2011.09.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 09/03/2011] [Indexed: 12/19/2022]
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Turunen HT, Sipilä P, Pujianto DA, Damdimopoulos AE, Björkgren I, Huhtaniemi I, Poutanen M. Members of the murine Pate family are predominantly expressed in the epididymis in a segment-specific fashion and regulated by androgens and other testicular factors. Reprod Biol Endocrinol 2011; 9:128. [PMID: 21942998 PMCID: PMC3192744 DOI: 10.1186/1477-7827-9-128] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 09/26/2011] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Spermatozoa leaving the testis are not able to fertilize the egg in vivo. They must undergo further maturation in the epididymis. Proteins secreted to the epididymal lumen by the epithelial cells interact with the spermatozoa and enable these maturational changes, and are responsible for proper storage conditions before ejaculation. The present study was carried out in order to characterize the expression of a novel Pate (prostate and testis expression) gene family, coding for secreted cysteine-rich proteins, in the epididymis. METHODS Murine genome databases were searched and sequence comparisons were performed to identify members of the Pate gene family, and their expression profiles in several mouse tissues were characterized by RT-PCR. Alternate transcripts were identified by RT-PCR, sequencing and Northern hybridization. Also, to study the regulation of expression of Pate family genes by the testis, quantitative (q) RT-PCR analyses were performed to compare gene expression levels in the epididymides of intact mice, gonadectomized mice, and gonadectomized mice under testosterone replacement treatment. RESULTS A revised family tree of Pate genes is presented, including a previously uncharacterized Pate gene named Pate-X, and the data revealed that Acrv1 and Sslp1 should also be considered as members of the Pate family. Alternate splicing was observed for Pate-X, Pate-C and Pate-M. All the Pate genes studied are predominantly expressed in the epididymis, whereas expression in the testis and prostate is notably lower. Loss of androgens and/or testicular luminal factors was observed to affect the epididymal expression of several Pate genes. CONCLUSIONS We have characterized a gene cluster consisting of at least 14 expressed Pate gene members, including Acrv1, Sslp1 and a previously uncharacterized gene which we named Pate-X. The genes code for putatively secreted, cysteine-rich proteins with a TFP/Ly-6/uPAR domain. Members of the Pate gene cluster characterized are predominantly expressed in the murine epididymis, not in the testis or prostate, and are regulated by testicular factors. Similar proteins are present in venoms of several reptiles, and they are thought to mediate their effects by regulating certain ion channels, and are thus expected to have a clinical relevance in sperm maturation and epididymal infections.
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Affiliation(s)
- Heikki T Turunen
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- Turku Graduate School of Biomedical Sciences, Kiinamyllynkatu 13, FIN-20520, Turku, Finland
| | - Petra Sipilä
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- Turku Center for Disease Modeling, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
| | - Dwi Ari Pujianto
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- Department of Biology, Faculty of Medicine, University of Indonesia, Jakarta Pusat, Indonesia
| | - Anastasios E Damdimopoulos
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
| | - Ida Björkgren
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- Turku Graduate School of Biomedical Sciences, Kiinamyllynkatu 13, FIN-20520, Turku, Finland
| | - Ilpo Huhtaniemi
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- Institute of Reproductive and Developmental Biology, Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | - Matti Poutanen
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- Turku Center for Disease Modeling, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
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24
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Safavi-Hemami H, Siero WA, Kuang Z, Williamson NA, Karas JA, Page LR, MacMillan D, Callaghan B, Kompella SN, Adams DJ, Norton RS, Purcell AW. Embryonic toxin expression in the cone snail Conus victoriae: primed to kill or divergent function? J Biol Chem 2011; 286:22546-57. [PMID: 21504902 DOI: 10.1074/jbc.m110.217703] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Predatory marine cone snails (genus Conus) utilize complex venoms mainly composed of small peptide toxins that target voltage- and ligand-gated ion channels in their prey. Although the venoms of a number of cone snail species have been intensively profiled and functionally characterized, nothing is known about the initiation of venom expression at an early developmental stage. Here, we report on the expression of venom mRNA in embryos of Conus victoriae and the identification of novel α- and O-conotoxin sequences. Embryonic toxin mRNA expression is initiated well before differentiation of the venom gland, the organ of venom biosynthesis. Structural and functional studies revealed that the embryonic α-conotoxins exhibit the same basic three-dimensional structure as the most abundant adult toxin but significantly differ in their neurological targets. Based on these findings, we postulate that the venom repertoire of cone snails undergoes ontogenetic changes most likely reflecting differences in the biotic interactions of these animals with their prey, predators, or competitors. To our knowledge, this is the first study to show toxin mRNA transcripts in embryos, a finding that extends our understanding of the early onset of venom expression in animals and may suggest alternative functions of peptide toxins during development.
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Affiliation(s)
- Helena Safavi-Hemami
- Department of Biochemistry and Molecular Biology, University of Melbourne, 3010 Victoria, Australia
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25
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Naamati G, Askenazi M, Linial M. A predictor for toxin-like proteins exposes cell modulator candidates within viral genomes. Bioinformatics 2010; 26:i482-8. [PMID: 20823311 PMCID: PMC2935411 DOI: 10.1093/bioinformatics/btq375] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Motivation: Animal toxins operate by binding to receptors and ion channels. These proteins are short and vary in sequence, structure and function. Sporadic discoveries have also revealed endogenous toxin-like proteins in non-venomous organisms. Viral proteins are the largest group of quickly evolving proteomes. We tested the hypothesis that toxin-like proteins exist in viruses and that they act to modulate functions of their hosts. Results: We updated and improved a classifier for compact proteins resembling short animal toxins that is based on a machine-learning method. We applied it in a large-scale setting to identify toxin-like proteins among short viral proteins. Among the ∼26 000 representatives of such short proteins, 510 sequences were positively identified. We focused on the 19 highest scoring proteins. Among them, we identified conotoxin-like proteins, growth factors receptor-like proteins and anti-bacterial peptides. Our predictor was shown to enhance annotation inference for many ‘uncharacterized’ proteins. We conclude that our protocol can expose toxin-like proteins in unexplored niches including metagenomics data and enhance the systematic discovery of novel cell modulators for drug development. Availability: ClanTox is available at http://www.clantox.cs.huji.ac.il Contact:michall@cc.huji.ac.il
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Affiliation(s)
- Guy Naamati
- School of Computer Science and Engineering, Hebrew University of Jerusalem, Israel
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26
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Abstract
Toxins are detected in sporadic species along the evolutionary tree of the animal kingdom. Venomous animals include scorpions, snakes, bees, wasps, frogs and numerous animals living in the sea such as the stonefish, snail, jellyfish, hydra and more. Interestingly, proteins that share a common scaffold with animal toxins also exist in non-venomous species. However, due to their short length and primary sequence diversity, these, toxin-like proteins remain undetected by classical search engines and genome annotation tools. We construct a toxin classification machine and web server called ClanTox (Classifier of Animal Toxins) that is based on the extraction of sequence-driven features from the primary protein sequence followed by the application of a classification system trained on known animal toxins. For a given input list of sequences, from venomous or non-venomous settings, the ClanTox system predicts whether each sequence is toxin-like. ClanTox provides a ranked list of positively predicted candidates according to statistical confidence. For each protein, additional information is presented including the presence of a signal peptide, the number of cysteine residues and the associated functional annotations. ClanTox is a discovery-prediction tool for a relatively overlooked niche of toxin-like cell modulators, many of which are therapeutic agent candidates. The ClanTox web server is freely accessible at http://www.clantox.cs.huji.ac.il.
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Affiliation(s)
- Guy Naamati
- Computer Science and Engineering, The Hebrew University of Jerusalem, Israel
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27
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Abstract
The sequencing of the platypus genome has spurred investigations into the characterisation of the monotreme immune response. As the most divergent of extant mammals, the characterisation of the monotreme immune repertoire allows us to trace the evolutionary history of immunity in mammals and provide insights into the immune gene complement of ancestral mammals. The immune system of monotremes has remained largely uncharacterised due to the lack of specific immunological reagents and limited access to animals for experimentation. Early immunological studies focussed on the anatomy and physiology of the lymphoid system in the platypus. More recent molecular studies have focussed on characterisation of individual immunoglobulin, T-cell receptor and MHC genes in both the platypus and short-beaked echidna. Here, we review the published literature on the monotreme immune gene repertoire and provide new data generated from genome analysis on cytokines, Fc receptors and immunoglobulins. We present an overview of key gene families responsible for innate and adaptive immunity including the cathelicidins, defensins, T-cell receptors and the major histocompatibility complex (MHC) Class I and Class II antigens. We comment on the usefulness of these sequences for future studies into immunity, health and disease in monotremes.
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28
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Whittington CM, Papenfuss AT, Bansal P, Torres AM, Wong ESW, Deakin JE, Graves T, Alsop A, Schatzkamer K, Kremitzki C, Ponting CP, Temple-Smith P, Warren WC, Kuchel PW, Belov K. Defensins and the convergent evolution of platypus and reptile venom genes. Genome Res 2008; 18:986-94. [PMID: 18463304 DOI: 10.1101/gr.7149808] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
When the platypus (Ornithorhynchus anatinus) was first discovered, it was thought to be a taxidermist's hoax, as it has a blend of mammalian and reptilian features. It is a most remarkable mammal, not only because it lays eggs but also because it is venomous. Rather than delivering venom through a bite, as do snakes and shrews, male platypuses have venomous spurs on each hind leg. The platypus genome sequence provides a unique opportunity to unravel the evolutionary history of many of these interesting features. While searching the platypus genome for the sequences of antimicrobial defensin genes, we identified three Ornithorhynchus venom defensin-like peptide (OvDLP) genes, which produce the major components of platypus venom. We show that gene duplication and subsequent functional diversification of beta-defensins gave rise to these platypus OvDLPs. The OvDLP genes are located adjacent to the beta-defensins and share similar gene organization and peptide structures. Intriguingly, some species of snakes and lizards also produce venoms containing similar molecules called crotamines and crotamine-like peptides. This led us to trace the evolutionary origins of other components of platypus and reptile venom. Here we show that several venom components have evolved separately in the platypus and reptiles. Convergent evolution has repeatedly selected genes coding for proteins containing specific structural motifs as templates for venom molecules.
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Affiliation(s)
- Camilla M Whittington
- Faculty of Veterinary Science, University of Sydney, Sydney, New South Wales 2006, Australia
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29
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Bhutia SK, Maiti TK. Targeting tumors with peptides from natural sources. Trends Biotechnol 2008; 26:210-7. [PMID: 18295917 DOI: 10.1016/j.tibtech.2008.01.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2007] [Revised: 12/12/2007] [Accepted: 01/16/2008] [Indexed: 01/10/2023]
Abstract
Peptide-based therapies offer the potential for non-genotoxic, genotype-specific alternatives, or adjuvants, to the current range of traditional cancer treatments. Such a patient-tailored cancer-cell-directed therapeutic approach should have fewer side effects and could well be more effective than the current drug- or combination-based regimens. Here, we review the potential of novel natural anticancer peptides such as necrotic peptides, apoptotic peptides, function-blocking peptides, antiangiogenic peptides and immunostimulatory peptides in the context of their ability to induce tumor regression. We focus on the therapeutic prospects of anticancer peptides and their possible application in tumor therapy.
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Affiliation(s)
- Sujit K Bhutia
- Department of Biotechnology, Indian Institute of Technology, Kharagpur, West Bengal, India
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