Genome-Wide Analysis of Terpene Synthase Gene Family in Mentha longifolia and Catalytic Activity Analysis of a Single Terpene Synthase

Abstract

Terpenoids are a wide variety of natural products and terpene synthase (TPS) plays a key role in the biosynthesis of terpenoids. Mentha plants are rich in essential oils, whose main components are terpenoids, and their biosynthetic pathways have been basically elucidated. However, there is a lack of systematic identification and study of TPS in Mentha plants. In this work, we genome-widely identified and analyzed the TPS gene family in Mentha longifolia, a model plant for functional genomic research in the genus Mentha. A total of 63 TPS genes were identified in the M. longifolia genome sequence assembly, which could be divided into six subfamilies. The TPS-b subfamily had the largest number of genes, which might be related to the abundant monoterpenoids in Mentha plants. The TPS-e subfamily had 18 members and showed a significant species-specific expansion compared with other sequenced Lamiaceae plant species. The 63 TPS genes could be mapped to nine scaffolds of the M. longifolia genome sequence assembly and the distribution of these genes is uneven. Tandem duplicates and fragment duplicates contributed greatly to the increase in the number of TPS genes in M. longifolia. The conserved motifs (RR(X)8W, NSE/DTE, RXR, and DDXXD) were analyzed in M. longifolia TPSs, and significant differentiation was found between different subfamilies. Adaptive evolution analysis showed that M. longifolia TPSs were subjected to purifying selection after the species-specific expansion, and some amino acid residues under positive selection were identified. Furthermore, we also cloned and analyzed the catalytic activity of a single terpene synthase, MlongTPS29, which belongs to the TPS-b subfamily. MlongTPS29 could encode a limonene synthase and catalyze the biosynthesis of limonene, an important precursor of essential oils from the genus Mentha. This study provides useful information for the biosynthesis of terpenoids in the genus Mentha.

Alternate gene expression profiling of monoterpenes in Hymenocrater longiflorus as a novel pharmaceutical plant under water deficit

“…This result indicates that environmental stresses might play a role in activating some genes that are involved in both essential oils synthesis pathways and stress responsive genes. Nonetheless, the complex polyploidy levels in line with lack of genomic and transcriptomic information related to the majority of aromatic plants have limited further study even on model plants such as mint species 35 . In some studies 23 , 36 , 37 , associations between genes that are involved in ABA, jasmonic acid and gibberellin responsive pathways which are enhanced under specific stresses and the metabolite gene network have been reported.…”

“…According to Chen et al 35 , terpene synthase (TPS) gene family is largely involved in terpenes biosynthesis of Mentha longifolia . In their study, TPS family was divided into six subfamilies sharing a great number of mostly identical and some similar motifs.…”

The response of Hymenocrater longiflorus to water stress and proline application under in vitro cultivation

“…This result indicates that environmental stresses might play a role in activating some genes that are involved in both essential oils synthesis pathways and stress-responsive genes. Nonetheless, the complex polyploid levels in line with the lack of genomic and transcriptomic information related to the majority of aromatic plants have limited further study even on model plants such as mint species (Chen et al, 2021). In some studies (Alonso-Ramírez et al, 2009, Emamverdian et al, 2020, Pirbalouti et al, 2014, associations between genes that are involved in ABA, jasmonic acid and gibberellin responsive pathways which are enhanced under speci c stresses and the metabolite gene network has been reported.…”

“…According to Chen et al (2021), terpene synthase (TPS) gene family is largely involved in terpenes biosynthesis of Mentha longifolia. In their study, the TPS family was divided into six subfamilies sharing a great number of mostly identical and some similar motifs.…”

“…After that, different TPS genes catalyze these compounds into the precursors of monoterpenes and other secondary metabolites. The produced precursors are then modi ed by enzymatic activities transcribed from different enzyme genes (Chen et al, 2021).…”