Comparative analysis of genomic variations among different Cdo1 paralogs for salinity-adaptation in oysters.

Mingjie Zhao; Ao Li; Kexin Zhang; Wei Wang; Guofan Zhang; Li Li

doi:10.1016/j.cbd.2026.101913

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Comparative analysis of genomic variations among different Cdo1 paralogs for salinity-adaptation in oysters.

Mingjie Zhao·Ao Li·Kexin Zhang·Wei Wang·Guofan Zhang·Li Li

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Abstract

Under rapid climate change and anthropogenic activities, oysters, a global aquaculture species, are subjected to exacerbated culturing environments, especially for those living in in-shore estuarine species, such as Suminoe oysters Crassostrea ariakensis. This study aims to investigate the molecular mechanisms of salinity adaptation of C. ariakensis. We performed an expression genome-wide association study (eGWAS) to compare genetic regulation among 5 paralogous copies of a key salinity-related gene, cysteine dioxygenase 1 (Cdo1). A total of 40 significant eSNPs with 82 adjacent eGenes were identified in 2 copies (Cdo1_26639 and Cdo1_1666). We identified only trans-eSNPs for Cdo1_26639 and more cis-eSNPs for Cdo1_1666, and different eGenes for these 2 Cdo1 copies, which indicated that the expressional regulation of these paralogs may undergo distinct pathways. We identified 3 eGenes that exhibited identical expression patterns with Cdo1_26639 and Cdo1_1666, including 6-Pgdh, Trapp and tandem copy of Cdo1_27337. The expression correlation between Cdo1 copies and eGenes was enhanced under salinity stresses, suggesting the crucial role of eGenes in regulating Cdo1's expression in response to salinity changes. Our results provide comprehensive identification and comparison of eSNPs across different paralogous copies of one gene, along with insights into the molecular mechanisms underlying salinity tolerance, and genetic markers for breeding salinity-resistant oysters.

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Animals Salinity Cysteine Dioxygenase Adaptation, Physiological Crassostrea Polymorphism, Single Nucleotide Genome-Wide Association Study Genetic Variation Crassostrea ariakensis Environmental change Gene expression regulation Salinity adaptation eGWAS Journal Article Comparative Study

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Mingjie Zhao, Ao Li, Kexin Zhang, Wei Wang, Guofan Zhang, Li Li. 2026-06-19. Comparative analysis of genomic variations among different Cdo1 paralogs for salinity-adaptation in oysters.. https://doi.org/10.1016/j.cbd.2026.101913

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Journal Article; Comparative Study resource Adaptation, Physiological subject Animals subject Comparative Study subject Crassostrea subject Crassostrea ariakensis subject Cysteine Dioxygenase subject Environmental change subject Gene Expression Regulation subject Genetic Variation subject Genome-Wide Association Study subject Journal Article subject eGWAS subject

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