title: A versatile click-compatible monolignol probe to study lignin deposition in plant cell walls.
abstract: Lignin plays important structural and functional roles in plants by forming a hydrophobic matrix in secondary cell walls that enhances mechanical strength and resists microbial decay. While the importance of the lignin matrix is well documented and the biosynthetic pathways for monolignols are known, the process by which lignin precursors or monolignols are transported and polymerized to form this matrix remains a subject of considerable debate. In this study, we have synthesized and tested an analog of coniferyl alcohol that has been modified to contain an ethynyl group at the C-3 position. This modification enables fluorescent tagging and imaging of this molecule after its incorporation into plant tissue by click chemistry-assisted covalent labeling with a fluorescent azide dye, and confers a distinct Raman signature that could be used for Raman imaging. We found that this monolignol analog is incorporated into in vitro-polymerized dehydrogenation polymer (DHP) lignin and into root epidermal cell walls of 4-day-old Arabidopsis seedlings. Incorporation of the analog in stem sections of 6-week-old Arabidopsis thaliana plants and labeling with an Alexa-594 azide dye revealed the precise locations of new lignin polymerization. Results from this study indicate that this molecule can provide high-resolution localization of lignification during plant cell wall maturation and lignin matrix assembly.
authors.affiliation: Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Jyotsna L
authors.initials: JL
authors.lastname: Pandey
authors.affiliation: Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, United States of America; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Brett G
authors.initials: BG
authors.lastname: Diehl
authors.affiliation: Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Tom L
authors.initials: TL
authors.lastname: Richard
authors.affiliation: Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, United States of America; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Gong
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America; Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Anderson
mesh_terms: D017360:Arabidopsis / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000737:chemistry; D005470:Fluorometry; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D009930:Organic Chemicals / Q000737:chemistry; D010636:Phenols / Q000737:chemistry; D018517:Plant Roots / Q000378:metabolism; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D013059:Spectrum Analysis, Raman
chemical_list: C417664:Alexa594; D005456:Fluorescent Dyes; D009930:Organic Chemicals; D010636:Phenols; D011108:Polymers; D008031:Lignin; C010559:coniferyl alcohol