Comparative Proteomic Analysis Provides Insight into the Key Proteins as Potential Targets Involved in Malachite Green Inhibiting Reproduction of Ichthyophthirius Multifiliis

Abstract Background: Target identification is important for drug discovery. Unfortunately, no drug targets have been found in I. multifiliis until now and further limited development of the novel drug for Ichthyophthiriasis. Methods: In this study, an iTRAQ-based quantitative proteomic analysis was used to find the target of malachite green (MG), exhibiting greater efficacy than the existing drugs, against I. multifiliis trophonts in situ. We also verified the proteomic results by RT-qPCR, TEM, cell apoptosis assay.Results: Our results showed that major variations in protein abundance were found among many of the ribosome proteins, indicating ribosome might be a candidate target. Furthermore, GO and KEGG pathway analyses of differentially expressed proteins (DEPs) revealed that ribosome and PI3K-Akt signaling pathway were remarkably enriched. Taken together, the above DEPs were also verified by RT-qPCR and morphological observations. Conclusions: This study provides insights into the key proteins enriched in PI3K-Akt signal pathway and ribosome pathway as potential targets of MG inhibiting reproduction of I. multifiliis, which could be serve as targets for other less toxic drugs and be tested as potential treatments for I. multifiliis.