gibberellin

Decades ago researchers knocked out the genes that control early steps in gibberellin synthesis, but the result was plants that had deformed flowers and abnormal ears.

The lower stem nodes of these varieties make insufficient amounts of gibberellin to activate internode elongation.

Maturing female ferns express some genes that begin the production of gibberellin, but add a methyl ester chemical group to the precursor molecule before secreting it into the wet forest floor.

First, gibberellin levels increase and stimulate production of key flowering factors, one of which degrades gibberellin.

They figured out how to suppress corn genes that code for enzymes known as gibberellin 20 oxidases, which put the biochemical finishing touches on the hormone in particular parts of the plant.