Page 162 - PC2019 Program & Proceedings

PLANT CANADA 2019

S109. Molecular regulation of monoterpene metabolism in Lavandula
Mahmoud, S.
UBC Okanagan

Lavenders (Lavandula) are widely cultivated for their essential oils (EO), which are mainly constituted of
monoterpenes. We have developed genomics resources to facilitate the discovery of structural and
regulatory genes that control EO formation, secretion and storage in Lavandula. This presentation
summarizes recent findings concerning the molecular aspects of EO metabolism in these plants.
Specifically, recent progress in cloning and characterization of genes that control flower development,
and those that encode terpene synthases, terpene synthase regulators (transcription factors) and prenyl
transferases.

Soheil Mahmoud (soheil.mahmoud@ubc.ca)

S110. Functional study of Lavandula prenyl diphosphate synthase genes
*1
2
Adal, A.M. ; S. Mahmoud
1 UBC
2 UBC Okanagan

Lavandula essential oils are mainly composed of monoterpenes and a lesser amount of sesquiterpenes.
The flux of these terpenoids can be regulated by expression of terpene synthases and the amount of
supplied precursors, which are produced by short-chain isoprenyl diphosphate synthases (IDSs) from the
pools of isoprene units (IPP and DMAPP). The IDSs include geranyl diphosphate synthase (GPPS),
farnesyl diphosphate synthase (FPPS), and geranylgeranyl diphosphate synthase (GGPPS), which give
rise to monoterpenes, sesquiterpenes, and diterpenes, respectively. Although several studies have
focused on genes encoding terpene synthases, the biosynthesis of major terpenoid precursors has not been
determined in Lavandula. Here, we report the cloning and functional characterization of GPPS, FPPS and
GGPPS from L. x intermedia. The cloned Lavandula IDSs resemble those previously reported in mints.
LiGPPS is a heteromeric protein, composed of a large and a small subunit, while FPPS and GGPPS are
homomeric proteins. Recombinant GPPS, FPPS and GGPPS catalyzed the condensation of IPP with
DMAPP to form GPP, FPP, and GGPP, respectively. The small subunit of LiGPPS also interacted with
GGPPS, modifying this enzyme to produce GPP.

Ayelign M. Adal (ayelign@gmail.com)

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