Santalum album, L.

Zhang, Xinhua, Teixeira da Silva, Jaime A., Niu, Meiyun, Zhang, Ting, Liu, Huanfang, Zheng, Feng, Yuan, Yunfei, Li, Yuan, Fang, Lin, Zeng, Songjun & Ma, Guohua, 2021, Functional characterization of an Indian sandalwood (Santalum album L.) dual-localized bifunctional nerolidol / linalool synthase gene involved in stress response, Phytochemistry (112610) 183, pp. 1-12 : 5

3.1. Identification of a bifunctional nerolidol/linalool synthase in S. album

It is well known that essential oils extracted from the heartwood of sandalwood have important economic value. More than 100 terpenoids have been identified from the essential oil of sandalwood heartwood, comprising four main sesquiterpenols, α-, β-, and epi -β- santalol and α- exo -bergamotol, and a large number of minor components, such as bisabolol, (E)-nuciferol, and nerolidol ( Baldovini et al., 2011). Several TPSs in S. album , including SaSSY, SamonoTPS1, SasesquiTPS1, SaSQS1, SaSQS2, SaBS, and SaTPS1 to SaTPS3, have been functionally characterized ( Jones et al., 2008, 2011; Srivastava et al., 2015; Zhang et al., 2019). Additionally, a few TPSs in other Santalum species, such as SauSSY, SspiSSY, SauBS, SspiBS, and SspiTPS4, have been reported ( Jones et al., 2011; Moniodis et al., 2015). The majority of these TPSs contribute to aromatic essential oil in heartwood. SaTPS1, which mainly produced α- terpineol, (E)-α- bergamotene and sesquisabinene, and SaTPS3, which mainly produced (E)-β- farnesene, (E)-nerolidol and (E, E)-farnesol, were involved in the defensive response of S. album to biotic attack and abiotic stresses ( Zhang et al., 2019). In the present study, one novel TPS was selected from the unigenes of transcriptome data from S. album leaves in response to cold stress and further functionally characterized. Recombinant SaNES/LIS generates (E)-nerolidol and linalool utilizing FPP and GPP as substrates, respectively. Transient expression assays demonstrated that SaNES/LIS produced the same product in planta as that obtained in vitro. Combined with the expression pattern of the SaNES/LIS gene, SaNES/LIS might play another role that does not contribute to essential oils in sandalwood species.