Cucumber gibberellin 1-oxidase/desaturase initiates novel gibberellin catabolic pathways.

ABSTRACT: Bioactive gibberellins (GAs) are central regulators of plant growth and development, including seed development. GA homeostasis is achieved via complex biosynthetic and catabolic pathways, whose exact activities remain to be elucidated. Here, we isolated two cDNAs from mature or imbibed cucumber seeds with high sequence similarity to known GA 3-oxidases. We found that one enzyme (designated here CsGA3ox5) has GA 3-oxidation activity. However, the second enzyme (designated CsGA1ox/ds) performed multiple reactions, including 1β-oxidation and 9,11-desaturation of GAs, but was lacking the 3-oxidation activity. CsGA1ox/ds overexpression in Arabidopsis plants resulted in severely dwarfed plants that could be rescued by the exogenous application of bioactive GA₄, confirming that

SUBMITTER: Pimenta Lange MJ 

PROVIDER: S-EPMC7307207 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature