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Xiang Y, Shi Y, Sun L, Liang W, Chen K, Li C. Novel ApeC-containing protein mediates the recognition and internalization of Vibrio splendidus in Apostichopus japonicus. Int J Biol Macromol 2024; 275:133737. [PMID: 38986992 DOI: 10.1016/j.ijbiomac.2024.133737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 06/26/2024] [Accepted: 07/06/2024] [Indexed: 07/12/2024]
Abstract
Pattern recognition receptors (PRRs) mediate the innate immune responses and play a crucial role in host defense against pathogen infections. Apextrin C-terminal (ApeC)-containing proteins (ACPs), a newly discovered class of PRRs specific to invertebrates, recognize pathogens through their ApeC domain as intracellular or extracellular effectors. However, the other immunological functions of ACPs remain unclear. In this study, a membrane-localized ACP receptor was identified in the sea cucumber Apostichopus japonicus (denoted as AjACP1). The ApeC domain of AjACP1, which was located outside of its cell membrane, exhibited the capability to recognize and aggregate Vibrio splendidus. AjACP1 was upregulated upon V. splendidus infection, internalizing into the cytoplasm of coelomocytes. AjACP1 overexpression enhanced the phagocytic activity of coelomocytes against V. splendidus, while knockdown of AjACP1 by RNA interfere inhibited coelomocyte endocytosis. Inhibitor experiments indicated that AjACP1 regulated coelomocyte phagocytosis through the actin-dependent endocytic signaling pathway. Further investigation revealed that AjACP1 interacted with the subunit of the actin-related protein 2/3 complex ARPC2, promoting F-actin polymerization and cytoskeletal rearrangement and thereby affecting the coelomocyte phagocytosis of V. splendidus via the actin-dependent endocytic signaling pathway. As a novel membrane PRR, AjACP1 mediates the recognition and phagocytic activity of coelomocytes against V. splendidus through the AjACP1-ARPC2-F-actin polymerization and cytoskeletal rearrangement pathway.
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Affiliation(s)
- Yangxi Xiang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Yue Shi
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Lianlian Sun
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Weikang Liang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Kaiyu Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Chenghua Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, Zhejiang 315211, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
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Li H, Nie H, Li D, Wang B, Huo Z, Su Y, Yan X. Transcriptome analysis provides new insights into the immune response of Ruditapes philippinarum infected with Vibrio alginolyticus. FISH & SHELLFISH IMMUNOLOGY 2024; 148:109468. [PMID: 38432537 DOI: 10.1016/j.fsi.2024.109468] [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: 11/21/2023] [Revised: 02/17/2024] [Accepted: 02/25/2024] [Indexed: 03/05/2024]
Abstract
Manila clam (Ruditapes philippinarum) is a bivalve species with commercial value, but it is easily infected by pathogenic microorganisms in aquaculture, which restricts the shellfish industry. Notably, the impact of Vibrio alginolyticus on clam culture is obvious. In this study, RNA-seq was performed to analyze clam hepatopancreas tissue in 48 h (challenge group, G48h) and 96 h (challenge group, G96h) after infection with V. alginolyticus and 0 h after injection of PBS (control group, C). The results showed that a total of 1670 differentially expressed genes were detected in the G48h vs C group, and 1427 differentially expressed genes were detected in the G96h vs C group. In addition, KEGG analysis showed that DEGs were significantly enriched in pathways such as Lysosome and Mitophagy. Moreover, 15 immune related DEGs were selected for qRT-PCR analysis to verify the accuracy of RNA-seq, and the results showed that the expression level of DEGs was consistent with that of RNA-seq. Therefore, the results obtained in this study provides a preliminary understanding of the immune defense of R. philippinarum and molecular insights for genetic breeding of V. alginolyticus resistance in Manila clam.
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Affiliation(s)
- Hongda Li
- College of Fisheries and Life Science, Dalian Ocean University, 116023 Dalian, China; Engineering Research Center of Shellfish Culture and Breeding in Liaoning Province, Dalian Ocean University, 116023 Dalian, China
| | - Hongtao Nie
- College of Fisheries and Life Science, Dalian Ocean University, 116023 Dalian, China; Engineering Research Center of Shellfish Culture and Breeding in Liaoning Province, Dalian Ocean University, 116023 Dalian, China.
| | - Dongdong Li
- College of Fisheries and Life Science, Dalian Ocean University, 116023 Dalian, China; Engineering Research Center of Shellfish Culture and Breeding in Liaoning Province, Dalian Ocean University, 116023 Dalian, China
| | - Bin Wang
- Dalian Jintuo Aquatic Food Co., Ltd, 116000 Dalian, China
| | - Zhongming Huo
- College of Fisheries and Life Science, Dalian Ocean University, 116023 Dalian, China; Engineering Research Center of Shellfish Culture and Breeding in Liaoning Province, Dalian Ocean University, 116023 Dalian, China
| | - Yanming Su
- College of Fisheries and Life Science, Dalian Ocean University, 116023 Dalian, China.
| | - Xiwu Yan
- College of Fisheries and Life Science, Dalian Ocean University, 116023 Dalian, China; Engineering Research Center of Shellfish Culture and Breeding in Liaoning Province, Dalian Ocean University, 116023 Dalian, China
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Li F, Gong X, Zhou Y, Geng Q, Jiang Y, Yao L, Qu M, Tan Z. Integrated evidence of transcriptional, metabolic, and intestinal microbiota changes in Ruditapes philippinarum due to perfluorooctanoic acid-induced immunotoxicity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170341. [PMID: 38272093 DOI: 10.1016/j.scitotenv.2024.170341] [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: 07/24/2023] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024]
Abstract
Perfluorooctanoic acid (PFOA) is a toxic pollutant that bioaccumulates and is a significant public health concern due to its ubiquitous and persistent occurrence in global environments. Few studies have evaluated the adverse effects of PFOA on immune system, and this is particularly true for mollusks. Here, the PFOA-associated effects on immune system were evaluated in Ruditapes philippinarum using integrated analysis of metabolomes, microbiomes, and transcriptomes, providing evidence for possible mechanisms related to immunotoxicity. PFOA exposure caused clear variation in several important metabolites related to immune regulatory function within the haemolyph from R. philippinarum, while also altering key metabolic pathways, including those of lipids, unsaturated fatty acids (UFAs), and bile acids (BAs). After exposure to PFOAs, intestinal bacterial communities also clearly changed, with the predominant microflora becoming Mycoplasma and Bacteroidetes that are related to intestinal inflammation. Molecular analyses provided consistent results, wherein the expression of immune-related genes was significantly altered. Integration of the multi-'omics' analyses suggested that the TLR/MyD88/NF-kB pathway, along with PI3K-Akt-mTOR pathway, PPAR-mediated lipid metabolism and the autophagy signaling pathway, likely play important roles in initiating immunotoxic effects in R. philippinarum after PFOA exposure. These results provide further evidence that PFOA exposure can lead to immunologic dysfunction and also provide new insights into the mechanisms of PFAS alteration of bivalve immune function.
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Affiliation(s)
- Fengling Li
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China
| | - Xiuqiong Gong
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, People's Republic of China
| | - Yang Zhou
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, People's Republic of China
| | - Qianqian Geng
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China
| | - Yanhua Jiang
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China
| | - Lin Yao
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China
| | - Meng Qu
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China
| | - Zhijun Tan
- Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, People's Republic of China; Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, People's Republic of China.
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Colás-Ruiz NR, Pintado-Herrera MG, Santonocito M, Salerno B, Tonini F, Lara-Martín PA, Hampel M. Bioconcentration, biotransformation, and transcriptomic impact of the UV-filter 4-MBC in the manila clam Ruditapes philippinarum. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169178. [PMID: 38072265 DOI: 10.1016/j.scitotenv.2023.169178] [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: 09/24/2023] [Revised: 11/24/2023] [Accepted: 12/05/2023] [Indexed: 12/18/2023]
Abstract
Ultraviolet filters (UV-filters) are compounds extensively used in personal care products. These compounds are produced at increasing rates and discharged into marine ecosystems in unknown quantities and with no regulation, making them emerging contaminants. Among those, the UV-filter 4-Methylbenzylidene camphor (4-MBC) is used in a variety of personal care products such as sunscreens, soaps, or lipsticks. This high consumption has resulted in its presence in various environmental matrices at in concentrations ranging from ng to μg L-1. Very little is known, however, about the possible adverse effects in exposed non-target organisms. Our study presents novel data on the bioconcentration, toxicokinetics, and molecular effects of 4-MBC in a marine bivalve species of commercial interest, Ruditapes philippinarum (Manila clam). Organisms were exposed at two different concentrations (1.34 and 10.79 μg L-1) of 4-MBC for 7 days, followed by a 3-day depuration period (clean sea waters). Bioconcentration factors (BCF) were 3562 and 2229 L kg-1 for the low and high exposure concentrations, respectively, making this pollutant bioaccumulative according to REACH criteria. Up to six 4-MBC biotransformation products (BTPs)were identified, 2 of them for the first time. Transcriptomic analysis revealed between 658 and 1310 differently expressed genes (DEGs) after 4-MBC exposure. Functional and enrichment analysis of the DEGs showed the activation of the detoxification pathway to metabolize and excrete the bioconcentrated 4-MBC, which also involved energy depletion and caused an impact on the metabolism of carbohydrates and lipids and in the oxidative phosphorylation pathways. Oxidative stress and immune response were also evidenced through the activation of cathepsins and the complement system. Such elucidation of the mode of action of a ubiquitous pollutant such as 4-MBC at the molecular level is valuable both from an environmental point of view and for the sustainable production of Manila clam, one of the most cultivated mollusk species worldwide.
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Affiliation(s)
- Nieves R Colás-Ruiz
- Faculty of Marine and Environmental Sciences (CASEM), University of Cadiz, 11510 Puerto Real, Cadiz, Spain.
| | - Marina G Pintado-Herrera
- Faculty of Marine and Environmental Sciences (CASEM), University of Cadiz, 11510 Puerto Real, Cadiz, Spain
| | - Melania Santonocito
- Instituto Universitario de Investigación Marina (INMAR), Campus de Excelencia Internacional del Mar (CEI•MAR), Universidad de Cadiz, Av. República Saharaui s/n, 11510 Puerto Real, Cadiz, Spain
| | - Barbara Salerno
- Instituto Universitario de Investigación Marina (INMAR), Campus de Excelencia Internacional del Mar (CEI•MAR), Universidad de Cadiz, Av. República Saharaui s/n, 11510 Puerto Real, Cadiz, Spain
| | - Federico Tonini
- Instituto Universitario de Investigación Marina (INMAR), Campus de Excelencia Internacional del Mar (CEI•MAR), Universidad de Cadiz, Av. República Saharaui s/n, 11510 Puerto Real, Cadiz, Spain
| | - Pablo A Lara-Martín
- Faculty of Marine and Environmental Sciences (CASEM), University of Cadiz, 11510 Puerto Real, Cadiz, Spain
| | - Miriam Hampel
- Faculty of Marine and Environmental Sciences (CASEM), University of Cadiz, 11510 Puerto Real, Cadiz, Spain
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Saco A, Rey-Campos M, Novoa B, Figueras A. Mussel antiviral transcriptome response and elimination of viral haemorrhagic septicaemia virus (VHSV). FISH & SHELLFISH IMMUNOLOGY 2023; 136:108735. [PMID: 37044187 DOI: 10.1016/j.fsi.2023.108735] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/31/2023] [Accepted: 04/05/2023] [Indexed: 06/19/2023]
Abstract
As filter-feeding bivalves, mussels have been traditionally studied as possible vectors of different bacterial or viral pathogens. The absence of a known viral pathogen in these bivalves makes it particularly interesting to study the interaction of the mussel innate immune system with a virus of interest. In the present work, mussels were challenged with viral haemorrhagic septicaemia virus (VHSV), which is a pathogen in several fish species. The viral load was eliminated after 24 h and mussels evidenced antiviral activity towards VHSV, demonstrating that the virus was recognized and eliminated by the immune system of the host and confirming that mussels are not VHSV vectors in the marine environment. The transcriptome activating the antiviral response was studied, revealing the involvement of cytoplasmic viral sensors with the subsequent activation of the JAK-STAT pathway and several downstream antiviral effectors. The inflammatory response was inhibited with the profound downregulation of MyD88, shifting the immune balance towards antiviral functions. High modulation of retrotransposon activity was observed, revealing a mechanism that facilitates the antiviral response and that had not been previously observed in these species. The expression of several inhibitors of apoptosis and apoptosis-promoting genes was modulated, although clear inhibition of apoptosis in bivalves after severe viral infection and subsequent disease was not observed in this study. Finally, the modulated expression of several long noncoding RNAs that were correlated with genes involved in the immune response was detected.
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Affiliation(s)
- Amaro Saco
- Institute of Marine Research (IIM-CSIC), Vigo, Galicia, Spain
| | | | - Beatriz Novoa
- Institute of Marine Research (IIM-CSIC), Vigo, Galicia, Spain
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Li J, Liu S, Zhang Y, Huang Q, Zhang H, OuYang J, Mao F, Fan H, Yi W, Dong M, Xu A, Huang S. Two novel mollusk short-form ApeC-containing proteins act as pattern recognition proteins for peptidoglycan. Front Immunol 2022; 13:971883. [PMID: 36275759 PMCID: PMC9585378 DOI: 10.3389/fimmu.2022.971883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 09/08/2022] [Indexed: 11/18/2022] Open
Abstract
The Apextrin C-terminal (ApeC) domain is a new protein domain largely specific to aquatic invertebrates. In amphioxus, a short-form ApeC-containing protein (ACP) family is capable of binding peptidoglycan (PGN) and agglutinating bacteria via its ApeC domain. However, the functions of ApeC in other phyla remain unknown. Here we examined 130 ACPs from gastropods and bivalves, the first and second biggest mollusk classes. They were classified into nine groups based on their phylogenetics and architectures, including three groups of short-form ACPs, one group of apextrins and two groups of ACPs of complex architectures. No groups have orthologs in other phyla and only four groups have members in both gastropods and bivalves, suggesting that mollusk ACPs are highly diversified. We selected one bivalve ACP (CgACP1; from the oyster Crossostrea gigas) and one gastropod ACP (BgACP1; from the snail Biomphalaria glabrata) for functional experiments. Both are highly-expressed, secreted short-form ACPs and hence comparable to the amphioxus ACPs previously reported. We found that recombinant CgACP1 and BgACP1 bound with yeasts and several bacteria with different affinities. They also agglutinated these microbes, but showed no inhibiting or killing effects. Further analyses show that both ACPs had high affinities to the Lys-type PGN from S. aureus but weak or no affinities to the DAP-type PGN from Bacillus subtilis. Both recombinant ACPs displayed weak or no affinities to other microbial cell wall components, including lipopolysaccharide (LPS), lipoteichoic acid (LTA), zymosan A, chitin, chitosan and cellulose, as well as to several PGN moieties, including muramyl dipeptide (MDP), N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc). Besides, CgACP1 had the highest expression in the gill and could be greatly up-regulated quickly after bacterial challenge. This is reminiscent of the amphioxus ACP1/2 which serve as essential mucus lectins in the gill. Taken together, the current findings from mollusk and amphioxus ACPs suggest several basic common traits for the ApeC domains, including the high affinity to Lys-type PGN, the bacterial binding and agglutinating capacity, and the role as mucus proteins to protect the mucosal surface.
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Affiliation(s)
- Jin Li
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Shumin Liu
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Yang Zhang
- Chinese Academy of Sciences Key Laboratory of Tropical Marine Bio-Resources and Ecology and Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Qiuyun Huang
- Chinese Academy of Sciences Key Laboratory of Tropical Marine Bio-Resources and Ecology and Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Hao Zhang
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jihua OuYang
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Fan Mao
- Chinese Academy of Sciences Key Laboratory of Tropical Marine Bio-Resources and Ecology and Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Huiping Fan
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Wenjie Yi
- Chinese Academy of Sciences Key Laboratory of Tropical Marine Bio-Resources and Ecology and Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Meiling Dong
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Anlong Xu
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
- *Correspondence: Anlong Xu, ; Shengfeng Huang,
| | - Shengfeng Huang
- Key Laboratory of Biocontrol, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- *Correspondence: Anlong Xu, ; Shengfeng Huang,
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