The immune function of prophenoloxidase from red swamp crayfish (Procambarus clarkii) in response to bacterial infection

Zhendong Qin; V Sarath Babu; Hanzuo Lin; Yunjia Dai; Hongyan Kou; Liehuan Chen; Jun Li; Lijuan Zhao; Li Lin

doi:10.1016/j.fsi.2019.05.005

The immune function of prophenoloxidase from red swamp crayfish (Procambarus clarkii) in response to bacterial infection

Fish Shellfish Immunol. 2019 Sep:92:83-90. doi: 10.1016/j.fsi.2019.05.005. Epub 2019 May 4.

Authors

Zhendong Qin¹, V Sarath Babu¹, Hanzuo Lin², Yunjia Dai³, Hongyan Kou¹, Liehuan Chen¹, Jun Li⁴, Lijuan Zhao⁵, Li Lin⁶

Affiliations

¹ Guangdong Provincial Water Environment and Aquatic Products Security Engineering Technology Research Center, Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong province, 510225, China.
² Faculty of Arts, University of British Columbia, Vancouver, British Columbia, V6T1W9, Canada.
³ National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China.
⁴ Guangdong Provincial Water Environment and Aquatic Products Security Engineering Technology Research Center, Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong province, 510225, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong province, 266071, PR China; School of Biological Sciences, Lake Superior State University, Sault Ste. Marie, MI, 49783, USA.
⁵ Guangdong Provincial Water Environment and Aquatic Products Security Engineering Technology Research Center, Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong province, 510225, China. Electronic address: 406856929@qq.com.
⁶ Guangdong Provincial Water Environment and Aquatic Products Security Engineering Technology Research Center, Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong province, 510225, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong province, 266071, PR China. Electronic address: linli@zhku.edu.cn.

PMID: 31059813
DOI: 10.1016/j.fsi.2019.05.005

Abstract

Prophenoloxidase (proPO) is the zymogen form of phenoloxidase (PO), a key enzyme in melanization cascade that has been co-opted in invertebrate immune reactions. There have been reported that proPO plays many essential roles in the crustacean immune system. However, little is known about the function of proPO from red swamp crayfish (Procambarus clarkii) which is an important cultured species worldwide. Here, we cloned and expressed proPO gene from red swamp crayfish (PcproPO). Subsequently, specific antibody against PcproPO was generated. The immune function of PcproPO was further characterized in vitro and in vivo. The results showed that the expression of PcproPO mRNA could be significantly up-regulated during the challenge of Gram-positive-negative (Vibrio parahaemolyticus) and Gram-positive-positive bacterial (Staphylococcus aureus). Furthermore, the purified recombinant PcproPO protein had a strong affinity binding to both bacteria and polysaccharides. In vivo knockdown of PcproPO could significantly reduce the crayfish bacterial clearance ability, resulting in the higher mortality of the crayfish during V. parahaemolyticus infection. In addition, in vitro knockdown of PcproPO in the hemocytes significantly reduced the phenoloxidase (PO) activity and the bacterial clearance ability, indicating that PcproPO might involve in hemocyte-mediated melanization. Our results will shed a new light on the immune function of PcproPO in the crayfish.

Keywords: Antibacterial activity; Melanization; Phenoloxidase; Procambarus clarkii; Prophenoloxidase.

MeSH terms

Animals
Arthropod Proteins / genetics
Arthropod Proteins / immunology
Astacoidea / genetics*
Astacoidea / immunology*
Astacoidea / microbiology
Catechol Oxidase / genetics*
Catechol Oxidase / immunology*
Enzyme Precursors / genetics*
Enzyme Precursors / immunology*
Gene Knockdown Techniques
Lipopolysaccharides / pharmacology
Peptidoglycan / pharmacology
Recombinant Proteins / genetics
Recombinant Proteins / immunology
Staphylococcus aureus / physiology
Teichoic Acids / pharmacology
Vibrio parahaemolyticus / physiology

Substances

Arthropod Proteins
Enzyme Precursors
Lipopolysaccharides
Peptidoglycan
Recombinant Proteins
Teichoic Acids
lipoteichoic acid
pro-phenoloxidase
Catechol Oxidase