Evolution of a novel phenolic pathway for pollen development.
Metabolic plasticity, which largely relies on the creation of new genes, is an essential feature of plant adaptation and speciation and has led to the evolution of large gene families. A typical example is provided by the diversification of the cytochrome P450 enzymes in plants. We describe here a retroposition, neofunctionalization, and duplication sequence that, via selective and local amino acid replacement, led to the evolution of a novel phenolic pathway in Brassicaceae. This pathway involves a cascade of six successive hydroxylations by two partially redundant cytochromes P450, leading to the formation of N1,N5-di(hydroxyferuloyl)-N10-sinapoylspermidine, a major pollen constituent and so-far-overlooked player in phenylpropanoid metabolism. This example shows how positive Darwinian selection can favor structured clusters of nonsynonymous substitutions that are needed for the transition of enzymes to new functions.
Institut de Biologie Moléculaire des Plantes, CNRS-UPR2357, Université de Strasbourg, 28 Rue Goethe, 67083 Strasbourg Cedex, France.
Michiyo
M
Matsuno
Vincent
V
Compagnon
Guillaume A
GA
Schoch
Martine
M
Schmitt
Delphine
D
Debayle
Jean-Etienne
JE
Bassard
Brigitte
B
Pollet
Alain
A
Hehn
Dimitri
D
Heintz
Pascaline
P
Ullmann
Catherine
C
Lapierre
François
F
Bernier
Jürgen
J
Ehlting
Danièle
D
Werck-Reichhart
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D029688:Brassica napus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D019607:Brassicaceae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019143:Evolution, Molecular; D020440:Gene Duplication; D006900:Hydroxylation; D053858:Metabolic Networks and Pathways; D008745:Methylation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011058:Pollen / Q000254:growth & development* / Q000378:metabolism; D034622:RNA Interference; D018626:Retroelements; D012641:Selection, Genetic; D013095:Spermidine / Q000031:analogs & derivatives* / Q000378:metabolism
C544114:N1,N5-di(hydroxyferuloyl)-N10-sinapoylspermidine; D010940:Plant Proteins; D018626:Retroelements; D003577:Cytochrome P-450 Enzyme System; D013095:Spermidine