Effect of arsenite on the proteome of earthworms Eisenia fetida

Abstract

Arsenic (As) is broadly distributed due to natural and anthropogenic sources, and it is toxic to organisms. This study aimed to investigate the proteomic response in earthworm exposed to As3+. Earthworms were exposed to As3+ in soil at 5–80 mg kg−1, and samples were collected after 60 days exposure. Two-dimensional electrophoresis (2-DE) was used to separate the proteins in earthworm homogenate, then differentially expressed proteins (DEPs) were identified using MALDI-TOF/TOF-MS analysis. After2-DE, 36 DEPs were found and 24 of them were successfully identified. 79.2% of DEPs were upregulated compared to the control group. The maximum fold change reached 53.8 in spot 3108 in the 80 mg kg−1 As group. Two proteins were not found in the control group but found in the As treated groups. Proteins were grouped into metabolism, signal transduction, stress-related, transport, regulation, and predicted/hypothetical protein categories based on their function. The protein—protein interaction between the DEPs indicated that serum albumin (ALB) is very important, related to 6 other proteins. Proteins were then verified by western blot, the results were in agreement with the proteomic analyses. The identification of induced or repressed proteins because of As3+ in earthworms is helpful to explore the underlying mechanisms of soil arsenic ecotoxicity.