Presence versus absence of CYP734A50 underlies the style-length dimorphism in primroses.
Heterostyly is a wide-spread floral adaptation to promote outbreeding, yet its genetic basis and evolutionary origin remain poorly understood. In Primula (primroses), heterostyly is controlled by the S-locus supergene that determines the reciprocal arrangement of reproductive organs and incompatibility between the two morphs. However, the identities of the component genes remain unknown. Here, we identify the Primula CYP734A50 gene, encoding a putative brassinosteroid-degrading enzyme, as the G locus that determines the style-length dimorphism. CYP734A50 is only present on the short-styled S-morph haplotype, it is specifically expressed in S-morph styles, and its loss or inactivation leads to long styles. The gene arose by a duplication specific to the Primulaceae lineage and shows an accelerated rate of molecular evolution. Thus, our results provide a mechanistic explanation for the Primula style-length dimorphism and begin to shed light on the evolution of the S-locus as a prime model for a complex plant supergene.
Institute for Biochemistry and Biology, University of Potsdam, Potsdam-Golm, Germany.
Cuong Nguyen
CN
Huu
Institute for Biochemistry and Biology, University of Potsdam, Potsdam-Golm, Germany.
Christian
0000-0002-1450-1864
C
Kappel
Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland.
Barbara
B
Keller
Institute for Biochemistry and Biology, University of Potsdam, Potsdam-Golm, Germany.
Adrien
A
Sicard
RIKEN Center for Sustainable Resource Science, Yokohama, Japan.
Yumiko
Y
Takebayashi
Department of Plant Science, University of Oxford, Oxford, United Kingdom.
Holger
H
Breuninger
Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland.|Natural History Museum, University of Oslo, Oslo, Norway.
Michael D
MD
Nowak
Institute for Biochemistry and Biology, University of Potsdam, Potsdam-Golm, Germany.
Isabel
0000-0001-5633-8068
I
Bäurle
Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
Axel
A
Himmelbach
Botanical Garden, University of Potsdam, Potsdam, Germany.
Michael
M
Burkart
Gartenbau Ebbing-Lohaus, Heiden, Germany.
Thomas
T
Ebbing-Lohaus
RIKEN Center for Sustainable Resource Science, Yokohama, Japan.
Hitoshi
H
Sakakibara
Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
Lothar
L
Altschmied
Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland.
Elena
E
Conti
Institute for Biochemistry and Biology, University of Potsdam, Potsdam-Golm, Germany.
Michael
0000-0001-8661-6911
M
Lenhard
D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D019143:Evolution, Molecular; D035264:Flowers / Q000033:anatomy & histology*; D020440:Gene Duplication; D020869:Gene Expression Profiling; D020868:Gene Silencing; D010940:Plant Proteins / Q000378:metabolism*; D031825:Primula / Q000033:anatomy & histology* / Q000201:enzymology* / Q000235:genetics; D029623:Primulaceae
D010940:Plant Proteins; D003577:Cytochrome P-450 Enzyme System
Primula; S-locus; brassinosteroids; chromosomes; genes; heterostyly; plant biology; supergene