Identification of PARPs and their potential role in longevity for larger Argopecten scallops to increase production

The bay scallop ( Argopecten irradians ) is an important species in the fisheries and aquaculture industries. However, the bay scallop’s small size, short lifespan (less than 14 months), and severe inbreeding depression present challenges for its sustainable development. Hybrids between the bay scallop and Peruvian scallop ( A. purpuratus ) are typically larger and longer-lived, likely due to longevity genes inherited from the Peruvian scallop (which has a lifespan of 7–10 years). Poly(ADP-ribose) polymerase (PARP) proteins play a crucial role in pathways related to aging. Specifically, DNA-dependent PARPs (PARP1, PARP2, and PARP3) are involved in maintaining genomic stability by responding to DNA breaks, but little is known about their role in the marine animals. In this study, we characterized the PARP gene family in both scallop species, identifying 38 members in the bay scallop and 30 in the Peruvian scallop, and observed differences in gene count, chromosomal localization, sequence structure, and alternative splicing between the two species. Cloning and sequencing of PARP1, PARP2, and PARP3 revealed significant differences in amino acid sequences between the two species that might affect protein function. Notably, reduced activity of PARP1–3 in short-lived bay scallops might potentially influence their lifespan. Exposure to ionizing radiation revealed substantial expression differences in PARPs and related genes between the two species. Additionally, the Peruvian scallop showed a significant upregulation of DNA-dependent PARPs, which may enhance its ability to maintain genomic stability. In conclusion, this study provides preliminary insights into the potential mechanisms by which PARPs may participate in DNA damage repair to maintain genomic stability for regulating the lifespan of marine bivalves. It may also identify potential biomarkers for breeding larger, longer-lived scallops to improve the production of their aquaculture. • Identified different numbers of PARPs in two Argopecten scallops with different lifespans. • The dramatically variations in PARPs may cause different catalytic activity for longevity in the two scallops. • PARPs and their related genes differently responded to ionizing radiation in the two scallops. • The higher expression of PARP2 and PARP3 in Peruvian scallops indicated the ability to maintain genomic stability. • PARP2 and PARP3 would be a potential biomarker for selecting larger-size hybrids.