Phosphorylated protein modification analysis on normal liver and Exo-celiac liver of Glyptosternum maculatum.

Background: This study aimed to reveal the biological function and molecular mechanism of phosphorylated proteins in the normal liver (NG) and Exo-celiac liver (WG) of Glyptosternum maculatum and potential plateau-adaption mechanisms of G. maculatum.

Methods: A multivariate analysis was performed on proteomic quantitative data (label-free group) and phosphorylated proteome data (phosphorylation group) to reveal protein characteristics. The differentially expressed proteins (DEPs) between NG and WG in the two groups were analysed. Enrichment analysis of these DEPs was performed prior to the protein-protein interaction (PPI) analysis. Finally, an integrated interaction network was constructed to reveal the biological mechanism of the DEP-mediated signal transduction process.

Result: The NG and WG samples in the phosphorylation group were well distinguished compared to the label-free group. A total of 49 and 313 DEPs were identified in the label-free and phosphorylation groups, respectively. These DEPs, including LIM and calponin homology domains-containing protein 1 (LIMCH1) and DEAD(Asp-Glu-Ala-Asp)-Box Helicase 51 (DDX51), were mainly assembled in functions such as cell adhesion. Two PPI networks were constructed using DEPs in the two groups. Finally, an integrated interaction network was constructed using co-DEP Ferredoxin 1 (FDX1) and associated pathways, including RNA transport.

Conclusion: LIMCH1 and DDX51 might play important roles in the organogenesis of normal liver and Exo-celiac liver in G. maculatum via the cell adhesion function. Moreover, FXD1 might be associated with the plateau-adaption mechanisms of G. maculatum via participation in the RNA transport pathway.