Dwarf 14 (D14) (D14)

Dwarf 14 (D14) is a member of the alpha/beta hydrolase superfamily that functions as the primary receptor for strigolactones, a class of plant hormones that regulate various aspects of plant growth and development (Hamiaux et al., 2012). Unlike most receptors, D14 possesses intrinsic catalytic activity, hydrolyzing its strigolactone ligand to form a covalently linked intermediate molecule that induces a significant conformational change in the receptor (Yao et al., 2016). This activated state allows D14 to interact with the F-box protein MAX2 (or D3 in rice), which is part of an SCF E3 ubiquitin ligase complex. This interaction leads to the polyubiquitination and subsequent proteasomal degradation of repressor proteins, such as D53 or SMAX1-LIKE (SMXL) family members, thereby releasing the inhibition of downstream transcriptional programs (Waters et al., 2017). Biologically, this pathway is crucial for inhibiting shoot branching, promoting root hair elongation, and facilitating symbiotic interactions with arbuscular mycorrhizal fungi. In an agricultural context, D14 and its homologs in parasitic plants (such as Striga) are major targets for the development of synthetic stimulants or inhibitors to manage weed infestations and optimize crop architecture (Zwanenburg et al., 2016).

Other names

DWARF14AtD14DAD2RMS3Strigolactone receptorKAI2-like proteins

D14 binds and hydrolyzes strigolactones, forming a covalent adduct that triggers a conformational change. This allows D14 to recruit the SCF-MAX2 ubiquitin ligase complex, leading to the proteasomal degradation of SMXL/D53 repressor proteins and the activation of downstream gene expression (Yao et al., 2016; Waters et al., 2017).