The lamprey (Lampetra japonica)， a representative of the jawless vertebrates， is the oldest extant species in the world. LIP-1， which has a jacalin-like domain and an aerolysin pore-forming domain， has previously been identified in Lampetra japonica. However， the structure and function of the LIP-1 protein have not been described. In this study， the LIP-1 gene was overexpressed in HeLa cells and H293T cells. The results showed that the overexpression of LIP-1 in HeLa cells significantly elevated LDH release (P < 0.05)， phosphatidylserine exposure and ROS accumulation. The overexpression of LIP-1 also had remarkable effects on the organelles in HeLa cells， while it had no effect on H293T cell organelles. Array data indicated that overexpression of LIP-1 primarily upregulated P53 signaling pathways in HeLa cells. Cell cycle assay results confirmed that LIP-1 caused arrest in the G/M phase of the cell cycle in HeLa cells. In summary， our findings provide insights into the function and characterization of LIP-1 genes in vertebrates and establish the foundation for further research into the biological function of LIP-1. Our observations suggest that this lamprey protein has the potential for use in new applications in the medical field.