Identification of Lipoxygenase gene repertoire of Cannabis sativa and functional characterization of CsLOX13 gene

• Published in: Plant science (Limerick) 2023-09, Vol.334, p.111780-111780, Article 111780
• Main Authors: Fayaz, Mohd, Kundan, Maridul, Gani, Umar, Sharma, Priyanka, Wajid, Mir Abdul, Katoch, Kajal, Babu, Vikash, Gairola, Sumeet, Misra, Prashant
• Format: Article
• Language: English
• Subjects: biosynthesis; cannabinoids; Cannabis sativa; enzyme activity; family; female flowers; females; Gene expression; gene expression regulation; genes; genetic markers; genetically modified organisms; genome-wide association study; growth and development; hexanoic acid; jasmonic acid; leaves; Lipoxygenase gene family; lipoxygenases; LOX activity; Methyl jasmonate; Nicotiana benthamiana; Nicotiana tabacum; Oxylipin biosynthesis; oxylipins; phylogeny; plant growth; plant hormones; secondary metabolites; stress response; sugars
• ISSN: 0168-9452; 1873-2259
• DOI: 10.1016/j.plantsci.2023.111780

Lipoxygenase (LOX) enzymes play a pivotal role in the biosynthesis of oxylipins. The phyto-oxilipins have been implicated in diverse aspects of plant biology, from regulating plant growth and development to providing tolerance against biotic and abiotic stresses. C. sativa is renowned for its bioactive secondary metabolites, namely cannabinoids. LOX route is assumed to be involved in the biosynthesis of hexanoic acid, which is one of the precursors of cannabinoids of C. sativa. For obvious reasons, the LOX gene family deserves thorough investigation in the C. sativa. Genome-wide analysis revealed the presence of 21 LOX genes in C. sativa, which can be further grouped into 13-LOX and 9-LOX depending upon their phylogeny as well as the enzyme activity. The promoter regions of the CsLOX genes were predicted to contain cis-acting elements involved in phytohormones responsiveness and stress response. The qRT-PCR-based expression analysis of 21 LOX genes revealed their differential expression in different plant parts (root, stem, young leaf, mature leaf, sugar leaf, and female flower). The majority of CsLOX genes displayed preferential expression in the female flower, which is the primary site for the biosynthesis of cannabinoids. The highest LOX activity and expression level of a jasmonate marker gene were reported in the female flowers among all the plant parts. Several CsLOX genes were found to be upregulated by MeJA treatment. Based on the transient expression in Nicotiana benthamiana and the development of stable Nicotiana tabacum transgenic lines, we demonstrate that CsLOX13 encodes functional lipoxygenase and play an important role in the biosynthesis of oxylipins. •C. sativa genome encodes 21 Lipoxygenase (CsLOX) genes, displaying differential expression in different plant parts.•Female flowers display the highest LOX enzyme activity and the expression level of jasmonate marker gene among different plant parts of C. sativa.•CsLOX gene promoters contain cis-acting elements involved in stress and phytohormone responses.•Several CsLOX genes are responsive to the methyl jasmonate treatment (MJ).•CsLOX13 encodes a functional lipoxygenase that plays an important role in the biosynthesis of jasmonates and possibly in hexanoic acid pathway.