1
|
Hu D, Xu F, Gao Z, Chen K, Guo W, Wang Z, Li S, Feng C. Pleiotropic immunoregulation by growth-blocking peptide in Ostrinia furnacalis. INSECT MOLECULAR BIOLOGY 2024; 33:270-282. [PMID: 38329162 DOI: 10.1111/imb.12898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 01/20/2024] [Indexed: 02/09/2024]
Abstract
Insects rely on their innate immune system to eliminate pathogenic microbes. As a system component, cytokines transmit intercellular signals to control immune responses. Growth-blocking peptide (GBP) is a member of the stress-responsive peptide family of cytokines found in several orders of insects, including Drosophila. However, the physiological role of GBP in defence against pathogens is not thoroughly understood. In this study, we explored the functions of GBP in a lepidopteran pest, Ostrinia furnacalis. Injection of recombinant O. furnacalis GBP (OfGBP) precursor (proGBP) and chemically synthesised GBP significantly induced the transcription of antimicrobial peptides (AMPs) and other immunity-related genes including immune deficiency (IMD) and Dorsal. The level of OfGBP mRNA was upregulated after bacterial infection. Knockdown of OfGBP expression led to a decrease in IMD, Relish, MyD88 and Dorsal mRNA levels. OfGBP induced phenoloxidase activity and affected hemocyte behaviours in O. furnacalis larvae. In summary, GBP is a potent cytokine, effectively regulating AMP synthesis, melanization response and cellular immunity to eliminate invading pathogens.
Collapse
Affiliation(s)
- Dongchun Hu
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Fuqiang Xu
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Zupeng Gao
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Kangkang Chen
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Wenlong Guo
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Zitian Wang
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Shuzhong Li
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Congjing Feng
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, China
| |
Collapse
|
2
|
Queiroga FR, Hegaret H, Carvalho WF, Naveira C, Rodrigues N, Santos FSD, Nascimento SM, Neves RAF. In vitro effects of the harmful benthic dinoflagellates Prorocentrum hoffmannianum and Ostreopsis cf. ovata on immune responses of the farmed oyster Crassostrea gasar. MARINE ENVIRONMENTAL RESEARCH 2024; 198:106503. [PMID: 38640692 DOI: 10.1016/j.marenvres.2024.106503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/08/2024] [Accepted: 04/10/2024] [Indexed: 04/21/2024]
Abstract
Oyster culture is a sustainable solution to food production. However, this activity can be severely impacted by the presence and proliferation of harmful microalgae such as the benthic dinoflagellates Prorocentrum hoffmannianum and Ostreopsis cf. ovata. This study aimed to evaluate the in vitro effects of P. hoffmannianum and O. cf. ovata on immune system cells (hemocytes) of the native cultured oyster Crassostrea gasar. The direct toxicity of both dinoflagellates was first evaluated assessing hemocyte viability exposed to eight concentrations of each HAB species. No reduction in hemocyte viability was found with the exposure to cell culture or the crude extract of P. hoffmannianum, but O. cf. ovata culture induced hemocyte death in a concentration-dependent manner. Ostreopsis cf. ovata concentration that promoted half of maximal reduction in hemocyte viability (EC50) was 779 cells mL-1. Posteriorly, hemocytes were exposed to both dinoflagellate cells and crude extracts to investigate their effects on hemocyte functional parameters. Despite no direct toxicity of the dinoflagellate cells, P. hoffmannianum extract caused a threefold increase in ROS production and decreased the phagocytosis rate by less than half. Ostreopsis cf. ovata cells and crude extracts also triggered an increase in ROS production (two-fold), but the phagocytosis rate was reduced (by half) only in response to the two lower cell concentrations. These results indicate a harmful potential of both dinoflagellates through a direct toxicity (only for O. cf. ovata) and functional impairment of hemocytes (both species) which could expose C. gasar oyster to opportunistic infections.
Collapse
Affiliation(s)
- Fernando Ramos Queiroga
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, F-29280 Plouzané, France; Research Group of Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil.
| | - Hélène Hegaret
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, F-29280 Plouzané, France
| | - Wanderson Fernandes Carvalho
- Research Group of Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| | - Clarissa Naveira
- Research Group of Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| | - Nathália Rodrigues
- Research Group of Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| | - Fernanda Silva Dos Santos
- Research Group of Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| | - Silvia Mattos Nascimento
- Marine Microalgae Laboratory, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| | - Raquel A F Neves
- Research Group of Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| |
Collapse
|
3
|
Ono M, Matsumura T, Sung EJ, Koyama T, Ochiai M, Shears SB, Hayakawa Y. Drosophila cytokine GBP2 exerts immune responses and regulates GBP1 expression through GPCR receptor Mthl10. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 167:104086. [PMID: 38295885 PMCID: PMC11232245 DOI: 10.1016/j.ibmb.2024.104086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/10/2023] [Accepted: 01/25/2024] [Indexed: 03/03/2024]
Abstract
Growth-blocking peptide (GBP), an insect cytokine, was first found in armyworm Mythimna separata. A functional analogue of GBP, stress-responsive peptide (SRP), was also identified in the same species. SRP gene expression has been demonstrated to be enhanced by GBP, indicating that both cytokines are organized within a hierarchical regulatory network. Although GBP1 (CG15917) and GBP2 (CG11395) have been identified in Drosophila melanogaster, immunological functions have only been characterized for GBP1. It is expected that the biological responses of two structurally similar peptides should be coordinated, but there is little information on this topic. Here, we demonstrate that GBP2 replicates the GBP1-mediated cellular immune response from Drosophila S2 cells. Moreover, the GBP2-induced response was silenced by pre-treatment with dsRNA targeting the GBP receptor gene, Mthl10. Furthermore, treatment of S2 cells with GBP2 enhanced GBP1 expression levels, but GBP1 did not affect GBP2 expression. GBP2 derived enhancement of GBP1 expression was not observed in the presence of GBP1, indicating that GBP2 is an upstream expressional regulator of a GBP1/GBP2 cytokine network. GBP2-induced enhancement of GBP1 expression was not observed in Mthl10 knockdown cells. Enhancement of GBP2 expression was observed in both Drosophila larvae and S2 cells under heat stress conditions; expressional enhancement of both GBP1 and GBP2 was eliminated in Mthl10 knockdown cells and larvae. Finally, Ca2+ mobilization assay in GCaMP3-expressing S2 cells demonstrated that GBP2 mobilizes Ca2+ upstream of Mthl10. Our finding revealed that Drosophila GBP1 and GBP2 control immune responses as well as their own expression levels through a hierarchical cytokine network, indicating that Drosophila GBP1/GBP2 system can be a simple model that is useful to investigate the detailed regulatory mechanism of related cytokine complexes.
Collapse
Affiliation(s)
- Masaya Ono
- Department of Applied Biological Sciences, Saga University, Saga, 840-8502, Japan
| | - Takashi Matsumura
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, 890-0065, Japan
| | - Eui Jae Sung
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Takashi Koyama
- Department of Biology, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Masanori Ochiai
- Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan
| | - Stephen B Shears
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Yoichi Hayakawa
- Department of Applied Biological Sciences, Saga University, Saga, 840-8502, Japan.
| |
Collapse
|