Pivotal role of pomca in the rapid growth of gynogenetic red crucian carp

Gynogenesis is a key technique for germplasm improvement in aquaculture. Previously, we successfully generated gynogenetic red crucian carp (GRCC) by artificial gynogenesis using blunt snout bream. The resulting GRCC exhibited significantly enhanced growth performance compared to ordinary red crucian carp (RCC). To identify key regulatory genes associated with this rapid growth phenotype, we conducted transcriptomic analysis of pituitary tissue and identified eight candidate genes. Among these, pomca —a gene known to be involved in growth regulation—was significantly downregulated in GRCC. To functionally validate its role, we created pomca -targeted RCC chimera via CRISPR-Cas9. At six months of age, these pomca -targeted RCC chimera showed significantly greater body weight, length, and width compared to wild-type (WT) controls ( P < 0.01), as well as increased muscle fiber area and diameter ( P < 0.05), indicating muscle fiber hypertrophy. Gene expression analysis suggested a potential mechanism involving a shift in neuropeptide balance, marked by elevated expression of the orexigenic gene npy . Notably, the expression patterns of key regulatory genes (e.g., mc4r , npy , agrp ) in pomca -targeted RCC chimera aligned with those observed in GRCC pituitary. Collectively, these findings demonstrate that decreased expression of pomca plays a substantial role in driving the accelerated growth observed in GRCC, and they also offer preliminary mechanistic insights into the regulatory pathways involved.