Open AccessWood forming tissue‐specific bicistronic expression of Pd GA 20ox1 and Ptr MYB 221 improves both the quality and quantity of woody biomass production in a hybrid poplar
Author(s) -
Cho JinSeong,
Jeon HyungWoo,
Kim MinHa,
Vo The K.,
Kim Jinsoo,
Park EungJun,
Choi YoungIm,
Lee Hyoshin,
Han KyungHwan,
Ko JaeHeung
Publication year - 2019
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.13036
Subject(s) - xylem , biology , biomass (ecology) , myb , transgene , gibberellin , lignin , genetically modified crops , secondary growth , botany , population , lignocellulosic biomass , microbiology and biotechnology , gene expression , gene , agronomy , biochemistry , demography , sociology
Summary With the exponential growth of the human population and industrial developments, research on renewable energy resources is required to alleviate environmental and economic impacts caused by the consumption of fossil fuels. In this study, we present a synthetic biological application of a wood forming tissue‐specific bicistronic gene expression system to improve both the quantity and quality of woody biomass to minimize undesirable growth penalties. Our transgenic poplars, designed to express both Pd GA 20ox1 (a GA 20‐oxidase from Pinus densiflora producing bioactive gibberellin, GA ) and Ptr MYB 221 (a MYB transcription factor negatively regulating lignin biosynthesis) under the developing xylem ( DX ) tissue‐specific promoter (i.e., DX 15::Pd GA 20ox1‐2A‐Ptr MYB 221 poplar), resulted in a 2‐fold increase in biomass quantity compared to wild‐type ( WT ), without undesirable growth defects. A similar phenotype was observed in transgenic Arabidopsis plants harboring the same gene constructs. These phenotypic consequences were further verified in the field experiments. Importantly, our transgenic poplars exhibited an improved quality of biomass with reduced lignin content (~16.0 wt%) but increased holocellulose content (~6.6 wt%). Furthermore, the saccharification efficiency of our transgenic poplar increased significantly by up to 8%. Our results demonstrate that the controlled production of both GA and a secondary wall modifying regulator in the same spatio‐temporal manner can be utilized as an efficient biotechnological tool for producing the desired multi‐purpose woody biomass.