The polymorphism of the genes/enzymes involved in the last two reductive steps of monolignol synthesis: what is the functional significance?
The polymorphism of genes and enzymes involved in the last two steps of monolignol synthesis is examined in the light of recent data coming from genomic studies and mutant/transformant analyses. The two catalytic activities considered--cinnamoyl-CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD)--are encoded by small multigene families. While some degree of diversification can be noted at the sequence level, it is often difficult to use this information to assign substrate specificities to each member of a gene family. Expression profiles, however, suggest for both CAD and CCR the existence of two sub-families: one devoted to developmental lignification, and the other involved in the synthesis of defence-related compounds.
Boudet
Alain-Michel
AM
UMR UPS/CNRS 5546, Pôle de biotechnologies végétale, 24, chemin de Borderouge, Auzeville, 31326 Castanet, France. amboudet@smcv.ups-tlse.fr
Hawkins
Simon
S
Rochange
Soizic
S
D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000445:Aldehyde Oxidoreductases / Q000378:metabolism*; D017343:Genes, Plant / Q000235:genetics*; D008031:Lignin / Q000096:biosynthesis*; D010084:Oxidation-Reduction; D010940:Plant Proteins / Q000378:metabolism*; D010944:Plants / Q000201:enzymology / Q000235:genetics; D011110:Polymorphism, Genetic
D010940:Plant Proteins; D008031:Lignin; D000429:Alcohol Oxidoreductases; C018656:cinnamyl alcohol dehydrogenase; D000445:Aldehyde Oxidoreductases; C019904:cinnamoyl CoA reductase