Wood formation in trees is a complex process governed by a multilayered genetic network. While model plants like Arabidopsis and poplar have revealed much about secondary cell wall (SCW) development, Ginkgo—a non‑flowering gymnosperm with a unique evolutionary history—has been largely overlooked. Most existing studies focus on angiosperms or conifers, leaving a critical gap in understanding how this “living fossil” orchestrates xylem development. Given these challenges, there is an urgent need for systematic investigation into the genetic architecture of wood traits in Ginkgo biloba.
Now, a team from the State Key Laboratory of Tree Genetics and Breeding, Co‑Innovation Center for Sustainable Forestry in Southern China at Nanjing Forestry University has taken on that challenge. Publishing (DOI: 10.1093/hr/uhag062) in Horticulture Research in 2026, the researchers combined genome‑wide association studies (GWAS), transcriptome‑wide association studies (TWAS), and weighted gene co‑expression network analysis (WGCNA) to pinpoint genes and regulatory networks governing 12 wood traits across 290 genetically diverse Ginkgo accessions.
The study uncovered a finely tuned cellulose synthesis machinery. Four cellulose synthase genes—GbCesa4, GbCesa7, GbCesa8A, and GbCesa8B—form a core complex that drives SCW cellulose production, mirroring the well‑known CesA4‑CesA7‑CesA8 model in Arabidopsis. These genes are co‑expressed with tubulin genes (TUBA and TUBB) and endoglucanase (EG), revealing a coordinated system linking cellulose biosynthesis with microtubule guidance and cell wall remodeling. Strikingly, loss‑of‑function mutations in GbCesa8B caused only a modest drop in cellulose content, suggesting functional redundancy between GbCesa8A and GbCesa8B—a safety net that may buffer against genetic disruptions. For hemicellulose, the team identified GbCSLA9A and GbCSLA9B as key mannan synthases, working alongside IRX9 and IRX14 in a co‑expression network that spans nucleotide sugar supply, polymer elongation, and post‑synthetic modification. The transcription factor MYB46 emerged as a potential master regulator of this mannan synthesis pathway. On the lignin front, TWAS flagged multiple genes across the entire biosynthetic cascade—from phenylalanine production (ADT/PDT) to phenylpropanoid conversion (PAL) and final polymerization (PER)—alongside positive regulators like MYB91 and eight basic helix-loop-helix (bHLH) transcription factors, including bHLH130, which may help steer metabolic flux toward lignin at the expense of competing flavonoid pathways.
“What excites us most is the elegance of the coordination we observed,” the authors said. “Cellulose, hemicellulose, and lignin don't operate in isolation—they're woven together through shared regulatory circuits. The co‑expression of CesA genes with microtubule components, for instance, suggests that the tree literally 'guides' its cell wall deposition along a cytoskeletal track. And the possible redundancy between GbCesa8A and GbCesa8B tells us that evolution has built fail‑safe mechanisms into this ancient species. These insights give us a new appreciation for how Ginkgo has sustained its structural integrity for over 200 million years.”
The implications extend far beyond basic science. With Ginkgo wood commanding high market value for furniture, construction, and specialty products, these findings provide tangible genetic targets for marker‑assisted breeding and gene‑editing strategies. By fine‑tuning the expression of key cellulose, hemicellulose, or lignin genes, breeders could potentially tailor wood density, stiffness, or processing efficiency to meet specific industrial demands. Moreover, the regulatory networks uncovered here—particularly the roles of MYB46, WRKY12, GATA9, and HB15—offer new levers for manipulating SCW thickness without compromising tree growth. As sustainable forestry becomes increasingly critical, understanding how to optimize timber quality at the genetic level will be essential for meeting global wood demand with fewer resources.
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References
DOI
10.1093/hr/uhag062
Original Source URL
https://doi.org/10.1093/hr/uhag062
Funding information
This study was supported by the Jiangsu Provincial Key Research and Development Program (BE2022373), the Independent Research Project of State Key Laboratory of Tree Genetics and Breeding (SKLTGBNJ2024–005), and the Graduate Research and Innovation Projects of Jiangsu Province (KYCX23_1245).
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.