Plant growth hormones act as master regulators of plant growth by controlling the activity of meristems. Meristems are specialized cells that give rise to all new plant organs, from stems and roots to flowers and fruits. By understanding how hormones interact with meristems, researchers have been able improve crops in remarkable ways.

A new review in Current Opinion in Plant Biology, coauthored by graduate student Prameela Awale and Professor Paula McSteen, delves into what is known about the network of proteins that interact with hormones within meristems, focusing on three key players in grasses: auxin, cytokinin, and gibberellic acid. The review focuses specifically on intercalary meristems, which promote longitudinal growth to stems and leaves.

Awale shares that this review is special to her not only because it is her first first-author paper, but because it helps bring attention to this fundamental player in plant biology.  “Although these meristems are crucial to plant architecture, they have not been the focus of a lot of study,” she says.

“This was the first time my lab reviewed the literature on intercalary meristems,” shares McSteen. “What brought them to our attention was that many of our hormone mutants that have defects in the inflorescence meristem also have plant height defects.  This observation indicated to us that the hormones function in both types of meristems.”