TY  - JOUR
A1  - Sicard, Adrien
A1  - Thamm, Anna
A1  - Marona, Cindy
A1  - Lee, Young Wha
A1  - Wahl, Vanessa
A1  - Stinchcombe, John R.
A1  - Wright, Stephen I.
A1  - Kappel, Christian
A1  - Lenhard, Michael
T1  - Repeated evolutionary changes of leaf morphology caused by mutations to a homeobox gene
JF  - Current biology
N2  - Elucidating the genetic basis of morphological changes in evolution remains a major challenge in biology [1-3]. Repeated independent trait changes are of particular interest because they can indicate adaptation in different lineages or genetic and developmental constraints on generating morphological variation [4-6]. In animals, changes to "hot spot" genes with minimal pleiotropy and large phenotypic effects underlie many cases of repeated morphological transitions [4-8]. By contrast, only few such genes have been identified from plants [8-11], limiting cross-kingdom comparisons of the principles of morphological evolution. Here, we demonstrate that the REDUCED COMPLEXITY (RCO) locus [12] underlies more than one naturally evolved change in leaf shape in the Brassicaceae. We show that the difference in leaf margin dissection between the sister species Capsella rubella and Capsella grandiflora is caused by cis-regulatory variation in the homeobox gene RCO-A, which alters its activity in the developing lobes of the leaf. Population genetic analyses in the ancestral C. grandiflora indicate that the more-active C. rubella haplotype is derived from a now rare or lost C. grandiflora haplotype via additional mutations. In Arabidopsis thaliana, the deletion of the RCO-A and RCO-B genes has contributed to its evolutionarily derived smooth leaf margin [12], suggesting the RCO locus as a candidate for an evolutionary hot spot. We also find that temperature-responsive expression of RCO-A can explain the phenotypic plasticity of leaf shape to ambient temperature in Capsella, suggesting a molecular basis for the well-known negative correlation between temperature and leaf margin dissection.
Y1  - 2014
U6  - https://doi.org/10.1016/j.cub.2014.06.061
SN  - 0960-9822
SN  - 1879-0445
VL  - 24
IS  - 16
SP  - 1880
EP  - 1886
PB  - Cell Press
CY  - Cambridge
ER  -