Molecular evolution of candidate male reproductive genes in the brown algal model Ectocarpus

BMC Evolutionary Biology

Research Article

Els J. M. Van Damme¹  Olivier De Clerck²  Agnieszka P. Lipinska² 

[1] Department of Molecular Biotechnology, Laboratory of Biochemistry and Glycobiology, Ghent University, Coupure Links 653, 9000, Ghent, Belgium;Phycology Research Group and Center for Molecular Phylogenetics and Evolution, Ghent University, Krijgslaan 281, Building S8, 9000, Ghent, Belgium;

关键词: Cell-cell recognition;    Gamete receptor;    Ectocarpus;    Brown algae;    Fertilization;   

DOI  :  10.1186/s12862-015-0577-9

 received in 2015-08-18, accepted in 2015-12-21,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundEvolutionary studies of genes that mediate recognition between sperm and egg contribute to our understanding of reproductive isolation and speciation. Surface receptors involved in fertilization are targets of sexual selection, reinforcement, and other evolutionary forces including positive selection. This observation was made across different lineages of the eukaryotic tree from land plants to mammals, and is particularly evident in free-spawning animals. Here we use the brown algal model species Ectocarpus (Phaeophyceae) to investigate the evolution of candidate gamete recognition proteins in a distant major phylogenetic group of eukaryotes.ResultsMale gamete specific genes were identified by comparing transcriptome data covering different stages of the Ectocarpus life cycle and screened for characteristics expected from gamete recognition receptors. Selected genes were sequenced in a representative number of strains from distant geographical locations and varying stages of reproductive isolation, to search for signatures of adaptive evolution. One of the genes (Esi0130_0068) showed evidence of selective pressure. Interestingly, that gene displayed domain similarities to the receptor for egg jelly (REJ) protein involved in sperm-egg recognition in sea urchins.ConclusionsWe have identified a male gamete specific gene with similarity to known gamete recognition receptors and signatures of adaptation. Altogether, this gene could contribute to gamete interaction during reproduction as well as reproductive isolation in Ectocarpus and is therefore a good candidate for further functional evaluation.

【 授权许可】

CC BY   
© Lipinska et al. 2016