Genetic Determinants for Enzymatic Digestion of Lignocellulosic Biomass Are Independent of Those for Lignin Abundance in a Maize Recombinant Inbred Population

Journal Article · Fri Jun 27 00:00:00 EDT 2014 · Plant Physiology

DOI:https://doi.org/10.1104/pp.114.242446· OSTI ID:1159773

Penning, Bryan W. ^[1]; Sykes, Robert W. ^[2]; Babcock, Nicholas C. ^[1]; Dugard, Christopher K. ^[1]; Held, Michael A. ^[1]; Klimek, John F. ^[1]; Shreve, Jacob T. ^[1]; Fowler, Matthew ^[2]; Ziebell, Angela ^[2]; Davis, Mark F. ^[2]; Decker, Stephen R. ^[2]; Turner, Geoffrey B. ^[2]; Mosier, Nathan S. ^[1]; Springer, Nathan M. ^[3]; Thimmapuram, Jyothi ^[1]; Weil, Clifford F. ^[1]; McCann, Maureen C. ^[1]; Carpita, Nicholas C. ^[1]

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1. Purdue Univ., West Lafayette, IN (United States)
2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
3. Univ. of Minnesota, St. Paul, MN (United States)

Biotechnological approaches to reduce or modify lignin in biomass crops are predicated on the assumption that it is the principal determinant of the recalcitrance of biomass to enzymatic digestion for biofuels production. We defined quantitative trait loci (QTL) in the Intermated B73 x 3 Mo17 recombinant inbred maize (Zea mays) population using pyrolysis molecular-beam mass spectrometry to establish stem lignin content and an enzymatic hydrolysis assay to measure glucose and xylose yield. Among five multiyear QTL for lignin abundance, two for 4-vinylphenol abundance, and four for glucose and/or xylose yield, not a single QTL for aromatic abundance and sugar yield was shared. A genome-wide association study for lignin abundance and sugar yield of the 282- member maize association panel provided candidate genes in the 11 QTL of the B73 and Mo17 parents but showed that many other alleles impacting these traits exist among this broader pool of maize genetic diversity. B73 and Mo17 genotypes exhibited large differences in gene expression in developing stem tissues independent of allelic variation. Combining these complementary genetic approaches provides a narrowed list of candidate genes. A cluster of SCARECROW-LIKE9 and SCARECROW-LIKE14 transcription factor genes provides exceptionally strong candidate genes emerging from the genome-wide association study. In addition to these and genes associated with cell wall metabolism, candidates include several other transcription factors associated with vascularization and fiber formation and components of cellular signaling pathways. Finally, these results provide new insights and strategies beyond the modification of lignin to enhance yields of biofuels from genetically modified biomass.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER)
• Grant/Contract Number: AC36-08GO28308; FOA–0000598; SC0000997; 0938033
• OSTI ID: 1159773
• Report Number(s): NREL/JA-5100-62316; MainId:15570; UUID:4d30f824-eefb-e311-8d7c-d89d67132a6d; MainAdminID:4048
• Journal Information: Plant Physiology, Vol. 165, Issue 4; ISSN 1532-2548
• Publisher: American Society of Plant Biologists
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
59 BASIC BIOLOGICAL SCIENCES
maize
plant cell wall
lignin
saccharification yield
quantitative trait loci (QTL)
recombinant inbred lines (RILs)
genome-wide association studies (GWAS)
genotype differential expression