Proteomics analysis reveals the regulatory effect of exosomes on innate immunity in Chlamys farreri

Abstract

Exosomes serve as an additional medium for inter- and intracellular communication, facilitating a range of biological processes in organisms through the transfer of bioactive substances. When shellfish responds to external stimuli, exosomes may regulate important immune responses by interacting with immune regulatory elements. However, the potential molecular basis between exosomes and innate immune in mollusks regulation remains to be explored. In this study, we used tandem mass tag (TMT) labeling technology to analyze the protein expression profiles of hemocytes stimulated by different sources of exosomes in Chlamys farreri, including LPS-derived exosomes stimulation group, PBS stimulation group, and untreated exosomes stimulation group. The results showed that the differentially expressed proteins (DEPs) screened in the LPS-stimulated group contained a variety of common immune-associated proteins, such as mono-ADP-ribosyltransferase PARP14 (PARP14), Dynein light chain cytoplasmic (Dynll2), Baculoviral IAP repeat-containing 1 (NAIP), MORC family CW-type zinc finger 3 (MORC3), ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase (CD38), and Calmodulin (CALM), compared to the other groups. The GO and KEGG functional annotation analysis showed that DEPs were involved in key biological functions and pathways, including cellular processes, response to stimulus, immune system process and autophagy functions, as well as signaling pathways such as the IL-17 Signaling Pathway, Phagosome, and Apoptosis. PPI network analysis revealed that TUBB4B and the down-regulated protein ACTB may act as important central regulatory proteins involved in the regulation of innate immune function. The results further indicated that exosomes were involved in the innate immune regulation by mediating the interaction between regulatory elements during cell communication. All these results demonstrate that exosomes play a core regulatory role in the innate immune defense mechanism of marine invertebrates, and also provide fundamental data for disease prevention and control and the breeding of disease-resistant cultured shellfish.