The salmonid myostatin gene family: a novel model for investigating mechanisms that influence duplicate gene fate

BMC Evolutionary Biology

Research Article

Buel D Rodgers¹  Takumu Niino²  Dilip K Garikipati²  Casey B Lawson²  David A Liberles³  Russell A Hermansen³  Vera Brok-Volchanskaya³  Melissa F Jackson⁴ 

[1] Department of Animal Sciences, Washington State University, 99164, Pullman, WA, USA;School of Molecular Biosciences, Washington State University, 99164, Pullman, WA, USA;Washington Center for Muscle Biology, Washington State University, 9916, Pullman, WA, USA;Department of Animal Sciences, Washington State University, 99164, Pullman, WA, USA;Washington Center for Muscle Biology, Washington State University, 9916, Pullman, WA, USA;Department of Molecular Biology, University of Wyoming, 82071, Laramie, WY, USA;School of Molecular Biosciences, Washington State University, 99164, Pullman, WA, USA;Washington Center for Muscle Biology, Washington State University, 9916, Pullman, WA, USA;

关键词: Salmon;    Myostatin;    Gene duplication;    Subfunctionalization;   

DOI  :  10.1186/1471-2148-12-202

 received in 2012-06-27, accepted in 2012-08-22,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundMost fishes possess two paralogs for myostatin, a muscle growth inhibitor, while salmonids are presumed to have four: mstn1a, mstn1b, mstn2a and mstn2b, a pseudogene. The mechanisms responsible for preserving these duplicates as well as the depth of mstn2b nonfunctionalization within the family remain unknown. We therefore characterized several genomic clones in order to better define species and gene phylogenies.ResultsGene organization and sequence conservation was particularly evident among paralog groupings and within salmonid subfamilies. All mstn2b sequences included in-frame stop codons, confirming its nonfunctionalization across taxa, although the indels and polymorphisms responsible often differed. For example, the specific indels within the Onchorhynchus tshawytscha and O. nerka genes were remarkably similar and differed equally from other mstn2b orthologs. A phylogenetic analysis weakly established a mstn2b clade including only these species, which coupled with a shared 51 base pair deletion might suggest a history involving hybridization or a shared phylogenetic history. Furthermore, mstn2 introns all lacked conserved splice site motifs, suggesting that the tissue-specific processing of mstn2a transcripts, but not those of mstn2b, is due to alternative cis regulation and is likely a common feature in salmonids. It also suggests that limited transcript processing may have contributed to mstn2b nonfunctionalization.ConclusionsPrevious studies revealed divergence within gene promoters while the current studies provide evidence for relaxed or positive selection in some coding sequence lineages. These results together suggest that the salmonid myostatin gene family is a novel resource for investigating mechanisms that regulate duplicate gene fate as paralog specific differences in gene expression, transcript processing and protein structure are all suggestive of active divergence.

【 授权许可】

Unknown   
© Lawson et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.