Evolved tooth gain in sticklebacks is associated with a cis-regulatory allele of Bmp6.
Proc Natl Acad Sci U S A
; 111(38): 13912-7, 2014 Sep 23.
Article
en En
| MEDLINE
| ID: mdl-25205810
ABSTRACT
Developmental genetic studies of evolved differences in morphology have led to the hypothesis that cis-regulatory changes often underlie morphological evolution. However, because most of these studies focus on evolved loss of traits, the genetic architecture and possible association with cis-regulatory changes of gain traits are less understood. Here we show that a derived benthic freshwater stickleback population has evolved an approximate twofold gain in ventral pharyngeal tooth number compared with their ancestral marine counterparts. Comparing laboratory-reared developmental time courses of a low-toothed marine population and this high-toothed benthic population reveals that increases in tooth number and tooth plate area and decreases in tooth spacing arise at late juvenile stages. Genome-wide linkage mapping identifies largely separate sets of quantitative trait loci affecting different aspects of dental patterning. One large-effect quantitative trait locus controlling tooth number fine-maps to a genomic region containing an excellent candidate gene, Bone morphogenetic protein 6 (Bmp6). Stickleback Bmp6 is expressed in developing teeth, and no coding changes are found between the high- and low-toothed populations. However, quantitative allele-specific expression assays of Bmp6 in developing teeth in F1 hybrids show that cis-regulatory changes have elevated the relative expression level of the freshwater benthic Bmp6 allele at late, but not early, stages of stickleback development. Collectively, our data support a model where a late-acting cis-regulatory up-regulation of Bmp6 expression underlies a significant increase in tooth number in derived benthic sticklebacks.
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Diente
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Evolución Molecular
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Smegmamorpha
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Proteínas de Peces
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Alelos
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Elementos Reguladores de la Transcripción
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Proteína Morfogenética Ósea 6
Tipo de estudio:
Risk_factors_studies
Límite:
Animals
Idioma:
En
Año:
2014
Tipo del documento:
Article