PT  - JOURNAL ARTICLE
AU  - Marie Sémon
AU  - Laurent Guéguen
AU  - Klara Steklikova
AU  - Marion Mouginot
AU  - Manon Peltier
AU  - Philippe Veber
AU  - Sophie Pantalacci
TI  - Developmental system drift in one tooth facilitates the adaptation of the other
AID  - 10.1101/2020.04.22.043422
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2020.04.22.043422
4099  - http://biorxiv.org/content/early/2022/04/08/2020.04.22.043422.short
4100  - http://biorxiv.org/content/early/2022/04/08/2020.04.22.043422.full
AB  - Serial organs, such as limbs or teeth, develop with the same sets of genes and regulatory sequences. Correlated evolution is expected by default, but decoupled evolution is often achieved, as in mouse with a morphological innovation in the upper, but not the lower molar. We studied developmental evolution of hamster and mouse molars with transcriptome data. We reveal a combination of three morphogenetic changes likely causing the new morphology of the mouse upper molar. Surprisingly, most of these changes are common with the lower molar and lower molar gene expression diverged as much as, and coevolved with, the upper molar.Hence, adaptation of the upper molar has involved changes in pleiotropic genes that also modified lower molar development but preserved its final phenotype. From the lower molar point of view, it is a case of Developmental systems drift (DSD). We think that DSD accommodates pleiotropy, explaining why in teeth and more generally in the body, the evolution of developmental gene expression is fast and correlates between organs.HIGHLIGHTS- The evolutionary innovation of mouse upper molar involves several morphogenetic changes- Most of the associated gene expression changes are shared with the mouse lower molar- Lower molar’s phenotype is conserved, thus its developmental gene expression drifted- Adaptation with pleiotropic genes drove developmental system drift in the other toothCompeting Interest StatementThe authors have declared no competing interest.