Genotype-Dependent Transcriptome Divergence Associated With Variation at vgll3 in Juvenile Gilthead Seabream (Sparus...

Area of Science:

• Aquaculture
• Genetics
• Developmental Biology

Background:

• Early development influences growth and maturation, critical for aquaculture productivity.
• The vestigial-like family member 3 gene (vgll3) is crucial for growth and maturation in various species.
• A single-nucleotide polymorphism in vgll3 (SNPvgll3) is under selection in farmed gilthead seabream (Sparus aurata).

Purpose of the Study:

• To investigate the impact of different SNPvgll3 genotypes (AA, AG, GG) on gene expression in juvenile gilthead seabream.
• To identify genotype-dependent regulatory signatures and their association with growth and maturation pathways.

Main Methods:

• Transcriptomic profiling of juvenile gilthead seabream with different SNPvgll3 genotypes.
• Quantitative PCR (qPCR) to measure vgll3 expression levels.
• Analysis of differential gene expression related to growth regulation and sexual maturation.

Main Results:

• Significant differences in transcriptome profiles were observed between the farming-associated GG genotype (lower vgll3 expression) and the AA genotype.
• Differential expression of genes involved in growth regulation, developmental processes, and sexual maturation (e.g., amh, cacng1b, casq2, tnnc2, igfn1.1) was associated with vgll3 genotype.
• The GG genotype showed significantly lower vgll3 expression compared to the AA genotype.

Conclusions:

• Findings support a conserved role for vgll3 in somatic growth and reproductive maturation pathways across teleosts.
• Genotype-specific transcriptomic divergence in vgll3 suggests conserved regulatory mechanisms, though its precise function requires further elucidation.
• This study underscores the importance of investigating genotype-dependent regulatory effects in non-model species like fish for evolutionary and developmental insights.