Molecular characterization and function of the lipid raft protein Lvflotillin-1A from Litopenaeus vannamei

• Published in: Fish & shellfish immunology 2022-09, Vol.128, p.380-388
• Main Authors: Li, Sujie, Shi, Hong, Ruan, Lingwei, Liu, Linmin, Wang, Chuanqi
• Format: Article
• Language: English
• ISSN: 1050-4648; 1095-9947
• DOI: 10.1016/j.fsi.2022.08.001

White spot syndrome virus (WSSV) can cause a contagious, high virulent and pandemic disease for crustaceans, especially shrimps. However, the molecular mechanism of WSSV pathogenesis remains unclear. Flotillins are lipid raft-associated proteins, which mainly include flotillin-1 and flotillin-2. They are involved in the formation of large heteromeric protein complexes engaged in diverse signalling pathways at the membrane-cytosol interface. They defined a clathrin-independent endocytic pathway in mammalian cells. Our previous studies suggested that shrimp flotillin-2 might mediate endocytosis involved in WSSV infection. To further explore the function of shrimp flotillin, a flotillin-1 homologous, Lvflotillin-1A was identified and characterized in Litopenaeus vanamei. The transcription of Lvflotillin-1A showed a significant decline at 12h post-infection, followed by complete recovery and a slight up-regulation after the WSSV challenge. Gene silencing revealed that inhibition of Lvflotillin-1A raised the virus infection, suggesting Lvflotillin-1A might play an important role in shrimp immunity. Furthermore, co-immunoprecipitation and immunofluorescence illustrated that Lvflotillin-1A and Lvflotillin-2 could form hetero-oligomers, and co-expression promoted the accumulation of intracellular vesicles. The study revealed that WSSV might up-regulate Lvflotillin-2 expression and alter the subcellular location of Lvflotillin-1 protein to facilitate virus infection. These results will provide information for understanding the interaction between WSSV and shrimp. •Lvflotillin-1A in Litopenaeus vanamei was identified and characterized.•Inhibition of Lvflotillin-1A expression could augment the virus infection in the early stage, suggesting that the Lvflotillin-1A might play an important role in shrimp immunity.•Lvflotillin-1A and 2 can be efficiently co-immunoprecipitated from cell extracts.•Co-expression of Lvflotillin-1A and 2 resulted in partial translocation of Lvflotillin-1A to the cytoplasm.