DAO, short for DIOXYGENASE OF AUXIN OXIDATION, is a key enzyme in plants. It belongs to a small subfamily of the 2-oxoglutarate and Fe(II) dependent dioxygenase superfamily. DAO is crucial for auxin homeostasis as it catalyzes the oxidative reaction of auxin, like indole-3-acetic acid (IAA), to its primary oxidative product 2-oxindole-3-acetic acid (oxIAA), which is then followed by conjugation reactions. This process is vital for plant growth and development [1].

Biochemical and genetic studies, likely including gene knockout (KO) or conditional knockout (CKO) models in plants (although not explicitly stated in the reference as mouse models), have revealed that DAO has critical physiological functions during plant growth and development. So far, DAO has been identified in three species by homology, suggesting its conserved role across different plant species [1].

In conclusion, DAO is essential for maintaining auxin homeostasis in plants, which is fundamental for various aspects of plant growth and development. Functional studies, potentially involving KO or CKO models in plants, have helped in understanding its role in these biological processes. This knowledge can contribute to the understanding of plant development mechanisms and may have implications for agricultural and plant-related research [1].

References:

1. Zhang, Jun, Peer, Wendy Ann. . Auxin homeostasis: the DAO of catabolism. In Journal of experimental botany, 68, 3145-3154. doi:10.1093/jxb/erx221. https://pubmed.ncbi.nlm.nih.gov/28666349/