hormone-homeostasis
Hormone homeostasis refers to the tightly regulated balance of plant hormones—such as auxins, cytokinins, gibberellins, and abscisic acid—achieved through coordinated synthesis, transport, signaling, and degradation. Maintaining this balance is essential for normal growth, development, and the ability to respond appropriately to environmental stresses. Disruptions in hormone homeostasis can lead to abnormal growth patterns, impaired stress tolerance, or developmental defects, making its study key to understanding how plants regulate their physiology.
open_in_new WikipediaPubMed · 2026-06-19
Plants use special enzymes to deactivate the growth hormone auxin by attaching different amino acids to it. This study shows that two families of these enzymes have distinct preferences — one favors aspartate, the other glutamine — a division that is conserved across plant species.
NtGH3.1a (and its Arabidopsis counterpart AtGH3.1) preferentially conjugates auxin (IAA) with aspartate, producing IAA-Asp as the main inactivation product.
NtGH3.6e (and Arabidopsis AtGH3.5/6) preferentially conjugates auxin with glutamine, producing the less-studied conjugates IAA-Gln and oxIAA-Gln.
Both enzyme types localize to the nucleus and cytoplasm regardless of auxin levels, suggesting their distribution is not dynamically regulated by the hormone they inactivate.
