5 responses to “Taxus brevifolia”

  1. philippe de spoelberch

    Yes, until the 1990’s we could sell or get rid of a lot of Taxus (baccata) shearings on our hedges and topiaries as these were pruned annually… Well now they go on the compost heap. Cheers from arboretum Wespelaar (Belgium). Philippe

  2. Richard Droker

    Why symbiotic fungi within yews (endophytes) also produce paclitaxel may be quite interesting – https://www.sciencedirect.com/science/article/pii/S0960982215011793

    more comprehensive – https://www.sciencedirect.com/science/article/pii/S0960982215009987

  3. Steve Edler

    Is there any suggestion of transmission of paclitaxel gene(s) between the tree & the fungus?

    1. Richard Droker

      I haven’t spent much time on this, but the question had came up in several papers I looked at:

      “As to why yew selected an endophyte that uses Taxol as its fungicidal mechanism, both partners might have been primed—sharing metabolic precursors for Taxol [12] and possibly having compatible signaling pathways.”

      (conclusion of this paper differs from previous and later papers)
      “The presence of these genes would require the extensive horizontal gene transfer (HGT) between the yew trees and multiple endophytic fungi, representing a pathway with more than 20 steps (Croteau et al. 2006). We find it difficult to believe that this entire pathway could have transferred in an arbitrary manner, and therefore we searched for evidence of DNA transfer involving potential taxane-synthesis gene clusters originating from Taxus plants. Whereas biosynthetic gene clusters are a common features in bacterial genomes and have also been described in fungi (Tudzynski and Hölter 1998; Zhang et al. 2004), there have been few reports of clustered metabolic pathways in plants, and those that do exist tend to be spread over larger genomic regions than their microbial counterparts (Field and Osbourn 2008; Field et al. 2011; Chu et al. 2011). The existence of taxane gene clusters in fungi and plants raises intriguing questions about the origin and evolution of these highly-specialized biosynthetic pathways, and the potential for HGT from fungi to Taxus trees. However, HGT between distantly-related organisms is a rare evolutionary event which is also constrained by the amount of genetic information transferred and genetic barriers involving incompatible regulation and codon usage. This contrasts sharply with the widespread observation of Taxol biosynthesis in many different endophytic fungi (Kurland et al. 2003).”

      “We found that paclitaxel biosynthetic gene candidates in P. aurantiogriseum NRRL 62431 have evolved independently and that horizontal gene transfer between this endophytic fungus and its plant host is unlikely.”

  4. Steve Edler

    Many thanks for the information Richard. I gather that the answer is probably no. Sorry for the delayed reply.

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