title: Pinoresinol reductase 1 impacts lignin distribution during secondary cell wall biosynthesis in Arabidopsis.
abstract: Pinoresinol reductase (PrR) catalyzes the conversion of the lignan (-)-pinoresinol to (-)-lariciresinol in Arabidopsis thaliana, where it is encoded by two genes, PrR1 and PrR2, that appear to act redundantly. PrR1 is highly expressed in lignified inflorescence stem tissue, whereas PrR2 expression is barely detectable in stems. Co-expression analysis has indicated that PrR1 is co-expressed with many characterized genes involved in secondary cell wall biosynthesis, whereas PrR2 expression clusters with a different set of genes. The promoter of the PrR1 gene is regulated by the secondary cell wall related transcription factors SND1 and MYB46. The loss-of-function mutant of PrR1 shows, in addition to elevated levels of pinoresinol, significantly decreased lignin content and a slightly altered lignin structure with lower abundance of cinnamyl alcohol end groups. Stimulated Raman scattering (SRS) microscopy analysis indicated that the lignin content of the prr1-1 loss-of-function mutant is similar to that of wild-type plants in xylem cells, which exhibit a normal phenotype, but is reduced in the fiber cells. Together, these data suggest an association of the lignan biosynthetic enzyme encoded by PrR1 with secondary cell wall biosynthesis in fiber cells.
authors.affiliation: Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Yining
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA.
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Yunqiao
authors.initials: Y
authors.lastname: Pu
authors.affiliation: Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Jackson
authors.affiliation: BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Engle
authors.affiliation: BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Madhavi Z
authors.initials: MZ
authors.lastname: Martin
authors.affiliation: BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Tschaplinski
authors.affiliation: Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Shi-You
authors.initials: SY
authors.lastname: Ding
authors.affiliation: Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Ragauskas
authors.affiliation: Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA. Electronic address: Richard.Dixon@unt.edu.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Dixon
mesh_terms: D017360:Arabidopsis / Q000166:cytology* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017705:Lignans / Q000096:biosynthesis; D008031:Lignin / Q000096:biosynthesis / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D017705:Lignans; C525564:Myb46 protein, Arabidopsis; C551849:PRR2 protein, Arabidopsis; C517318:SND1 protein, Arabidopsis; C411822:TOC1 protein, Arabidopsis; D014157:Transcription Factors; D008031:Lignin
keywords: Interfascicular fiber; Lignan; Lignin; Mutant; Stimulated Raman scattering microscopy