DNA polymorphism and selection at the bindin locus in three Strongylocentrotus sp. (Echinoidea)

BMC Genetics

Research Article

Evgeniy S. Balakirev¹  Francisco J. Ayala²  Maria Anisimova³  Vladimir A. Pavlyuchkov⁴ 

[1] A. V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch of the Russian Academy of Science, 690041, Vladivostok, Russia;Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, 92697-2525, Irvine, CA, USA;Far Eastern Federal University, 690950, Vladivostok, Russia;Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, 92697-2525, Irvine, CA, USA;Institute of Applied Simulation, School of Life Sciences and Facility Management, Zürich University of Applied Sciences, 8820, Wädenswil, Switzerland;Swiss Institute of Bioinformatics, 1015, Lausanne, Switzerland;Pacific Research Fisheries Centre (TINRO-Centre), 690600, Vladivostok, Russia;

关键词: Intron Region;    Noncoding Region;    Neutrality Test;    Synonymous Codon;    Codon Bias;   

DOI  :  10.1186/s12863-016-0374-5

 received in 2015-09-29, accepted in 2016-05-02,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundThe sperm gene bindin encodes a gamete recognition protein, which plays an important role in conspecific fertilization and reproductive isolation of sea urchins. Molecular evolution of the gene has been extensively investigated with the attention focused on the protein coding regions. Intron evolution has been investigated to a much lesser extent. We have studied nucleotide variability in the complete bindin locus, including two exons and one intron, in the sea urchin Strongylocentrotus intermedius represented by two morphological forms. We have also analyzed all available bindin sequences for two other sea urchin species, S. pallidus and S. droebachiensis.ResultsThe results show that the bindin sequences from the two forms of S. intermedius are intermingled with no evidence of genetic divergence; however, the forms exhibit slightly different patterns in bindin variability. The level of the bindin nucleotide diversity is close for S. intermedius and S. droebachiensis, but noticeably higher for S. pallidus. The distribution of variability is non-uniform along the gene; however there are striking similarities among the species, indicating similar evolutionary trends in this gene engaged in reproductive function. The patterns of nucleotide variability and divergence are radically different in the bindin coding and intron regions. Positive selection is detected in the bindin coding region. The neutrality tests as well as the maximum likelihood approaches suggest the action of diversifying selection in the bindin intron.ConclusionsSignificant deviation from neutrality has been detected in the bindin coding region and suggested in the intron, indicating the possible functional importance of the bindin intron variability. To clarify the question concerning possible involvement of diversifying selection in the bindin intron evolution more data combining population genetic and functional approaches are necessary.

【 授权许可】

CC BY   
© Balakirev et al. 2016