Aihong Wei, Fan'e Zeng, Rongxin Liang, Shixi Liang, Qiao Cheng, Yu Xie, Zhengjun Wu, Tongxiang Zou, Jinlong Huang
The invasive freshwater gastropod Pomacea canaliculata relies heavily on calcium for shell biomineralization and environmental adaptation. Previous studies on its biomineralization mainly focused on shell protein composition and chemically synthesized calcium supplements. Whether it actively utilizes snail shells and chicken eggshells as well as the underlying molecular regulatory mechanisms, remain poorly understood. In this study, we verified that P. canaliculata could actively ingest dried snail shells and chicken eggshells. Inductively coupled plasma mass spectrometry detection showed that supplementation with the two natural snail shells and chicken eggshells significantly elevated calcium accumulation in the mantle. Transcriptome sequencing revealed that a total of 296 and 99 differentially expressed genes in mantle tissues were screened in the snail shell group (S-SS) and eggshell group (S-ES), respectively. Functional enrichment analysis suggested that snail shell calcium activated lipid metabolism and G-protein-dependent calcium signaling pathways, while chicken eggshells calcium mainly induced ribosome and glycosyltransferase-related functions. Different calcium sources triggered distinct molecular regulatory strategies for shell biomineralization: snail shell calcium optimized calcium uptake via lipid remodeling and calcium signal transduction, and chicken eggshells calcium promoted the synthesis of shell organic matrix by enhancing protein translation. Protein-protein interaction network identified TLR2 as the universal hub gene responding to both calcium sources, indicating an integration of biomineralization processes with calcium nutrition and immune homeostasis. This work elucidates the molecular responses of P. canaliculata mantle to natural snail shells and chicken eggshells, and provides new insights into its biomineralization and adaptive strategies in freshwater environments.