Related Experiment Video
Updated: Feb 4, 2026

A Workflow for the Quantitative Assessment of the Endophytic and Epiphytic Bacterial Microbiomes of the Bark of Populus trichocarpa
Published on: June 27, 2025
CAD1 and CCR2 protein complex formation in monolignol biosynthesis in Populus trichocarpa
Xiaojing Yan1,2, Jie Liu3, Hoon Kim4
1State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, 100091, China.
Abstract:
Lignin is the major phenolic polymer in plant secondary cell walls and is polymerized from monomeric subunits, the monolignols. Eleven enzyme families are implicated in monolignol biosynthesis. Here, we studied the functions of members of the cinnamyl alcohol dehydrogenase (CAD) and cinnamoyl-CoA reductase (CCR) families in wood formation in Populus trichocarpa, including the regulatory effects of their transcripts and protein activities on monolignol biosynthesis. Enzyme activity assays from stem-differentiating xylem (SDX) proteins showed that RNAi suppression of PtrCAD1 in P. trichocarpa transgenics caused a reduction in SDX CCR activity. RNAi suppression of PtrCCR2, the only CCR member highly expressed in SDX, caused a reciprocal reduction in SDX protein CAD activities. The enzyme assays of mixed and coexpressed recombinant proteins supported physical interactions between PtrCAD1 and PtrCCR2. Biomolecular fluorescence complementation and pull-down/co-immunoprecipitation experiments supported a hypothesis of PtrCAD1/PtrCCR2 heterodimer formation. These results provide evidence for the formation of PtrCAD1/PtrCCR2 protein complexes in monolignol biosynthesis in planta.
More Related Videos
10:41The Logic, Experimental Steps, and Potential of Heterologous Natural Product Biosynthesis Featuring the Complex Antibiotic Erythromycin A Produced Through E. coli
Published on: January 13, 2013
06:39Author Spotlight: Characterization of Low-Affinity Protein Interactions in Solution Using MassFluidix Technology
Published on: January 26, 2024
Related Concept Videos
Formation of Complex Ions
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Protein Complex Assembly
Protein Complexes with Interchangeable Parts
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
Protein Complexes with Interchangeable Parts
Biosynthesis in Bacteria