Phenotypic plasticity is an important evolutionary mechanism that enables organisms to alter their trait to adapt to rapid environmental change. Genetic variation in phenotypic plasticity, also known as genotype-environment interaction (G×E), is a key component leading to phenotypic variation in response to the environmental change. However, the understanding of how G×E effects shape different plasticity patterns of environmental responsive traits is limited.
Recently, the research team led by Prof. LI Li from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) demonstrated that the G×E effects of cis-variations in the triglyceride lipase Atgl shaped trade-offs between constitutive expression and plastic expression of Atgl gene expression and triglyceride content in response to the environment.
The study was published in Molecular Ecology on Dec. 24.
The acute heat stress experiment discovered trade-offs between constitutive expression and plastic expression of environmentally responsive trait triglyceride content and the major gene Atgl gene expression in two congeneric oyster species (Crassostrea gigas and Crassostrea angulata), with the relatively more heat-tolerant C. angulata exhibiting higher constitutive expression and lower plasticity changes.
The divergent pattern of phenotypic plasticity was revealed to be potentially mediated by the G and G×E effects of cis-variation of the Atgl promoter region, which regulated by non-environmental responsive transcription factor Nono and the environmental responsive transcription factor heterogeneous nuclear ribonucleoprotein K (Hnrnpk).
"This study provides a proxy to deeply understand how G×E effects contribute to the formation of adaptive traits," said DU Mingyang, first author of the study.
"We are utilizing the relevant molecular modules to improve the heat tolerance of a new variety of oysters," said Prof. LI, corresponding author of the study.
Schematic representation of divergent Atgl plastic expression pattern regulated by cis-variations and trans-factors in C. gigas and C. angulata.
Mingyang Du, Chaogang Wang, Zhuxiang Jiang, Rihao Cong, Ao Li, Wei Wang, Guofan Zhang, Li Li*. (2024). The genotype-by-environment effects of cis-variations in the Atgl promoter mediate the divergent pattern of phenotypic plasticity for temperature adaptation in two congeneric oyster species. Molecular Ecology.
(Text by DU Mingyang)
(Editor: ZHANG Yiyi)