Abstract

By differential proteomics analysis, it was found that the expression level of IDH3α (Isocitrate dehydrogenase 3α) in mouse liver was significantly increased under the stress of Aflatoxin B₁. To validate the result of differential proteomics analysis, fluorescence quantitative PCR was used to detect the changing trend of idh3α mRNA volume induced by Aflatoxin B₁ in mouse liver. The result showed that the expression volume of idh3αmRNA showed an increasing trend with the increase of Aflatoxin B₁ concentration, which corresponded with the result of differential proteomics analysis. The protokaryon expression vector for idh3α was constructed in the study with pET28a as a recipient plasmid. The expression vector (pET28a-idh3α) was used to transform BL21, after which the positive expression strain (Escherichia coli BL21/pET28a-idh3α) was induced to express with 100 mmol/L IPTG under 28°C for 4 h, and the prokaryotic expression product of IDH3α was successfully detected by SDS-PAGE electrophoresis. The molecule structure of IDH3α was predicted by bioinformatics analysis, and the results showed that the total number of negatively and positively charged residues were 42 and 39, respectively. Five hydrohpobic domains were predicted in the protein, and its average hydrophobicity was -0.069. There was 43% α-helix and 20% β-pleated sheet in the molecule, and the tertiary structure of IDH3α was constituted by 12 α-helices and 12 β-pleated sheets. Based on the results of bioinformatics analysis, the fragments of 1-17 and 112-123 residues of IDH3α were selected as candidates for further effective polyclonal antibody preparation. The results of this study paved way for further exploration of the role of idh3α in the process of liver carceration induced by Aflatoxin B₁.

Key words: IDH3α, aflatoxinB₁, liver, canceration, bioinformatics analysis.