Interactions between brassinosteroids and gibberellins: synthesis or signaling?
journal contribution
posted on 2023-05-22, 00:12authored byJohn RossJohn Ross, Quittenden, LJ
Plants contain three major growth-promoting plant hormones: auxin, gibberellins (GAs), and brassinosteroids (BRs), although other hormones also promote growth in certain circumstances. Possible interactions between the major three growth hormones have received much attention over the decades. In 2012, three articles proposed that the BRs and GAs can interact at the signaling level (Bai et al., 2012; Gallego-Bartolome et al., 2012; Li et al., 2012), and since then, this has become an accepted model (Figure 1; Oh et al., 2014; Wang et al., 2014; Davie're and Achard, 2016). This “signaling” model posits that DELLA proteins, which are negative regulators of GA signaling that are degraded by bioactive GA, physically interact with positive regulators of the BR response, BZR1 proteins (Bai et al., 2012; Gallego- Bartolome et al., 2012; Li et al., 2012). The DELLA-BZR1 interaction interferes with the function of BZR1 proteins, thereby reducing growth.