title: Genetic and molecular basis of grass cell-wall degradability. I. Lignin-cell wall matrix interactions.
abstract: Lignification limits grass cell-wall digestion by herbivores. Lignification is spatially and temporally regulated, and lignin characteristics differ between cell walls, plant tissues, and plant parts. Grass lignins are anchored within walls by ferulate and diferulate cross-links, p-coumarate cyclodimers, and possibly benzyl ester and ether cross-links. Cell-wall degradability is regulated by lignin concentration, cross-linking, and hydrophobicity but not directly by most variations in lignin composition or structure. Genetic manipulation of lignification can improve grass cell-wall degradability, but the degree of success will depend on genetic background, plant modification techniques employed, and analytical methods used to characterize cell walls.
authors.affiliation: US Dairy Forage Research Center, USDA-Agricultural Research Service, 1925 Linden Drive West, Madison, WI 53706, USA. jgrabber@wisc.edu
authors.forename: John H
authors.initials: JH
authors.lastname: Grabber
authors.forename: John
authors.initials: J
authors.lastname: Ralph
authors.forename: Catherine
authors.initials: C
authors.lastname: Lapierre
authors.forename: Yves
authors.initials: Y
authors.lastname: Barrière
mesh_terms: D000821:Animal Feed; D000818:Animals; D002473:Cell Wall / Q000502:physiology*; D002934:Cinnamates / Q000032:analysis / Q000378:metabolism; D004063:Digestion; D014644:Genetic Variation; D008031:Lignin / Q000096:biosynthesis / Q000502:physiology*; D035261:Plant Components, Aerial / Q000502:physiology; D006109:Poaceae / Q000235:genetics / Q000502:physiology*
chemical_list: D002934:Cinnamates; D008031:Lignin