Signatures of selection in Mulinia lateralis underpinning its rapid adaptation to laboratory conditions

Abstract

The dwarf surf clam, Mulinia lateralis, is considered as a model species for bivalves because of its rapid growth and short generation time. Recently, successful breeding of this species for multiple generations in our laboratory revealed its acquisition of adaptive advantages during artificial breeding. In this study, 310 individuals from five different generations were genotyped with 22,196 single nucleotide polymorphisms (SNPs) with the aim of uncovering the genetic basis of their adaptation to laboratory conditions. Results revealed that M. lateralis consistently maintained high genetic diversity across generations, characterized by high observed heterozygosity (Ho: 0.2733–0.2934) and low levels of inbreeding (Fis: −0.0244–0.0261). Population analysis indicated low levels of genetic differentiation among generations of M. lateralis during artificial breeding (Fst <0.05). In total, 316 genomic regions exhibited divergent selection, with 168 regions under positive selection. Furthermore, 227 candidate genes were identified in the positive selection regions, which have functions including growth, stress resistance, and reproduction. Notably, certain selection signatures with significantly higher Fst value were detected in genes associated with male reproduction, such as GAL3ST1, IFT88, and TSSK2, which were significantly upregulated during artificial breeding. This suggests a potential role of sperm‐associated genes in the rapid evolutionary response of M. lateralis to selection in laboratory conditions. Overall, our findings highlight the phenotypic and genetic changes, as well as selection signatures, in M. lateralis during artificial breeding. This contributes to understanding their adaptation to laboratory conditions and underscores the potential for using this species to explore the adaptive evolution of bivalves.

Identification of Copy Number Variations and Selection Signatures in Wannan Spotted Pigs by Whole Genome Sequencing Data: A Preliminary Study

“…Galactose-3-O-sulfotransferase 1 (GAL3ST1), also known as cerebroside sulfotransferase (CST), is involved in spermatogenesis [31]. The GAL3ST1 was found selected in (dwarf surf clam) and associated with male reproduction [32]. By observing GAL3ST1 knockout mice, it was found that males displayed sterility, which resulted from a block in spermatogenesis before the first meiotic division [33].…”