High levels of linkage disequilibrium and associations with forage quality at a phenylalanine ammonia-lyase locus in European maize (Zea mays L.) inbreds.
Forage quality of maize is influenced by both the content and structure of lignin in the cell wall. Phenylalanine Ammonia-Lyase (PAL) catalyzes the first step in lignin biosynthesis in plants; the deamination of L-phenylalanine to cinnamic acid. Successive enzymatic steps lead to the formation of three monolignols, constituting the complex structure of lignin. We have cloned and sequenced a PAL genomic sequence from 32 maize inbred lines currently employed in forage maize breeding programs in Europe. Low nucleotide diversity and excessive linkage disequilibrium (LD) was identified at this PAL locus, possibly reflecting selective constrains resulting from PAL being the first enzyme in the monolignol, and other, pathways. While the association analysis was affected by extended LD and population structure, several individual polymorphisms were associated with neutral detergent fiber (not considering population structure) and a single polymorphism was associated with in vitro digestibility of organic matter (considering population structure).
Andersen
Jeppe R
JR
Danish Institute of Agricultural Sciences, Research Center Flakkebjerg, 4200, Slagelse, Denmark.
Zein
Imad
I
Wenzel
Gerhard
G
Krützfeldt
Birte
B
Eder
Joachim
J
Ouzunova
Milena
M
Lübberstedt
Thomas
T
D005819:Genetic Markers; D007178:Inbreeding; D015810:Linkage Disequilibrium / Q000235:genetics*; D009711:Nucleotides / Q000235:genetics; D010650:Phenylalanine Ammonia-Lyase / Q000235:genetics* / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics* / Q000502:physiology
D005819:Genetic Markers; D009711:Nucleotides; D010650:Phenylalanine Ammonia-Lyase