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Duan Wu

Publications and source records attributed to Duan Wu.

3 recordsLinked to original sources

Metabolome-based genome-wide association study provides genetic insights into the andrographolide accumulation in Andrographis paniculata.

Andrographis paniculata is a distinctive medicinal plant that produces andrographolide-related metabolites, a class of diterpenoid compounds with potent anti-inflammatory activities. To elucidate the genetic mechanisms underlying the biosynthesis of these compounds, we perform comprehensive metabolic profiling and whole-genome resequencing on a natural population of A. paniculata. Population structure analysis reveals four distinct subgroups characterized by low intra-group genetic diversity but significant inter-group differentiation. Through metabolome-based genome-wide association study, we identify a significant locus associated with 14-deoxyandrographolide content. This locus harbors the candidate gene ApNB-ARC25 (CXN00004106), which encodes an NB-ARC domain-containing resistance protein. Functional characterization using virus-induced gene silencing shows that silencing of ApNB-ARC25 significantly reduces andrographolide accumulation and downregulates expressions of key genes in the andrographolide biosynthetic pathway. Heterologous overexpression of ApNB-ARC25 in rice not only improves resistance to blast disease but also enhances diterpenoid phytoalexin production. Our findings reveal that ApNB-ARC25 promotes diterpenoid accumulation and andrographolide biosynthesis by upregulating key genes involved in terpenoid backbone formation and diterpenoid synthesis. This work not only expands the functional understanding of the ApNB-ARC gene family but also provides a genetic resource for enhancing valuable compound accumulation in medicinal plants, offering important insights into the molecular regulation of medicinal metabolite biosynthesis.

Diterpenes↗

Comparative genomic analysis of Artemisia argyi reveals asymmetric expansion of terpene synthases and conservation of artemisinin biosynthesis.

Artemisia argyi, a perennial herb of the Asteraceae family, possesses significant therapeutic and economic value. We present a 7.88 Gb chromosome-level haplotype-resolved genome assembly, revealing its unique evolutionary trajectory. The karyotype (2n = 34) of A. argyi is that of an autotetraploid, which underwent gametic chromosome fusion prior to species-specific whole-genome duplication (WGD-3). The genome exhibits pronounced multivalent chromosome pairing and frequent recombination among homologous groups. Asymmetrical evolution following WGD-3 is a hallmark feature, evidenced by imbalanced allelic gene loss and widespread neofunctionalization. The terpene synthase (TPS) gene family exemplifies this pattern, having expanded through four duplication events in A. argyi. Recent tandem duplications and allelic functional differentiation have generated substantial gene functional diversity. Notably, we identified a tandem-duplicated six-copy ADS homolog (AarADS)-a key TPS gene in the artemisinin biosynthetic pathway of Artemisia annua (AanADS)-localized exclusively to a single chromosome in A. argyi. Unlike AanADS, which converts farnesyl pyrophosphate (FPP) to amorpha-4,11-diene, AarADS catalyzes FPP to α-bisabolol. Evolutionary analysis suggested that AanADS acquired its specialized function via a derived mutation in the A. annua lineage. This study elucidates the genomic evolution underpinning A. argyi's distinctive medicinal properties.

Alkyl and Aryl Transferases↗

[Fast 3D surface rendering for CT or MR image on a personal computer].

Objective. To design a 3D surface reconstruction algorithm capable of reconstructing 3D shapes of the organs, bones and tissues rapidly from CT or MR image on a personal computer. Method. By transforming and decomposing the projection of the discrete 3D data field into shear transformation and warp transformation, a Shear-Warp algorithm realizing the 3D reconstruction was established. The algorithm reduce the amount of computation obviously. The 3D surface was reconstructed by using the principle of the parallel projection, basing on the Shear-Warp algorithm. Shear transformation was performed on the volume data at first. Then the warped 3D surface was obtained by making a threshold in the sheared space. The brightness of the 3D surface was calculated using Phong brightness model, and the final image was generated through the Warp transformation. Result. A direct 3D surface reconstruction algorithm was established basing on a principle of projection from the Shear-Warp algorithm, which was able to display 3D surface on a personal computer rapidly. Conclusion. Compared with other surface reconstruction algorithms, the proposed algorithm has the advantages of no preprocessing, no intermediate data are generated in the reconstruction. With this new algorithm, it is possible to realize fast 3D surface rendering for medical images on a personal computer without the support of any hardware accelerator.

Algorithms↗