Identificação e caracterização de polimorfismos em genes envolvidos na síntese, maturação e remodelação de colágeno em tambaqui (Colossoma macropomum)

Abstract

Collagen is one of the main structural proteins in teleost fish, being essential for tissue integrity, regeneration, growth and stability of the extracellular matrix. In tambaqui (Colossoma macropomum), a species of great importance to Brazilian aquaculture, there are still gaps in our understanding of the genetic basis of collagen-related genes, despite advances in genome sequencing. This study identified and characterised polymorphisms associated with collagen synthesis, maturation and remodelling using genotypic data generated by the genotyping-by-Sequencing (GBS) protocol. Initially, approximately 182,000 SNPs from 239 individuals from different locations in Brazil were analysed. The sequences were filtered, fractionated and aligned to the reference genome, resulting in the mapping of 2,374 sequences distributed across 48 extracellular matrix genes. After filtering by the 80×80 criterion, 251 high-quality sequences remained, which were used in the diversity and population structure analyses. Multivariate analyses, dendrograms, and phylogeny showed strong genetic structuring among populations, with well-defined regional groupings and greater divergence in the CE population. FST values revealed genomic heterogeneity and highlighted highly differentiated SNPs, suggesting possible signatures of selection in collagen-related genes. The results demonstrate significant genetic variability among tambaqui populations and indicate that certain regions of the extracellular matrix may be subject to different selective pressures, contributing to advances in management, conservation, and breeding programmes.