Molecular mechanisms underlying Grateloupia imbricata (Rhodophyta) carposporogenesis induced by methyl jasmonate

• Published in: Journal of phycology Vol. 53; no. 6; pp. 1340 - 1344
• Main Authors: Garcia‐Jimenez, Pilar, Montero‐Fernández, Montserrat, Robaina, Rafael R., Lane, C.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.12.2017
• Subjects: Acetates - metabolism; Algae; Algal Proteins - genetics; Algal Proteins - metabolism; Cyclopentanes - metabolism; Cytochrome; Cytochrome P450; Cytochromes; Fertility; Gene expression; Genes; Grateloupia; Jasmonic acid; Jasmonic acid carboxyl; jasmonic acid carboxyl methyl transferase; Leaves; Methyl jasmonate; methyl transferase; Molecular modelling; Ornithine; Ornithine decarboxylase; Oxidation; Oxylipins - metabolism; Plant Growth Regulators - metabolism; Proteins; Reactive oxygen species; red seaweed; Reproduction (biology); Rhodophyta - enzymology; Rhodophyta - genetics; Rhodophyta - growth & development; Seaweeds; Signal transduction; Signaling; Synthesis; Thalli; jasmonic acid carboxyl methyl transferase; ornithine decarboxylase; methyl jasmonate; red seaweed; methyl transferase; gene expression
• ISSN: 0022-3646; 1529-8817
• DOI: 10.1111/jpy.12594

When applied in vitro, methyl jasmonate is sensed by the red seaweed Grateloupia imbricate, substantially and visually affecting its carposporogenesis. However, although there is some understanding of the morphological changes induced by methyl jasmonate in vitro, little is known about the genes that are involved in red seaweed carposporogenesis and how their protein products act. For the work reported herein, the expression of genes in red seaweed that encode enzymes involved in the synthesis of methyl jasmonate (jasmonic acid carboxyl methyl transferase and a putative methyl transferase) was monitored. Additionally the genes involved in oxidation (cytochrome P450 and WD40), jasmonate synthesis, signal transduction, and regulation of reactive oxygen species (MYB), and reproduction (ornithine decarboxylase) were monitored. To determine when or if the aforementioned genes were expressed during cystocarp development, fertilized and fertile thalli were exposed to methyl jasmonate and gene expression was measured after 24 and 48 h. The results showed that methyl jasmonate promoted differential gene expression in fertilized thalli by 24 h and upregulated expression of the ornithine decarboxylase gene only by 48 h in fertile thalli (0.75 ± 003 copies · μL−1 at 24 h vs. 1.11 ± 0.04 copies · μL−1 at 48 h). We conclude that Ornithine decarboxylase expression involves methyl jasmonate signaling as well as development and maturation of cystocarps.