Figure 3.

Proposed Modes of Action of Plant IDPs.

The IDPs and IDRs are shown as olive coils, with filled red and green circles representing potential MoRFs; four- and seven-point stars represent the potential and phosphorylated sites, respectively. Orange ovals, light-green rectangles, and blue hexagons represent different protein partners with which IDRs fold into α-helix, β-strand, and irregular structure, respectively.

(A) An entirely disordered IDP binds to a metal ion, shown as a pink-filled circle (I), the membrane (II), and protein partners (III). Phosphorylation can induce differential binding. In this case, binding to membrane is prevented by phosphorylation (IV).

(B) A modular IDP with an IDR binds to protein partners, while the folded domain, shown as an olive sphere, binds to another target shown as a green block (I) or differential binding is induced by phosphorylation. In this case, binding to the partners being weakened by phosphorylation is shown (II).

(C) A disordered domain with an intramolecular masking interaction releases the active site (yellow oval) in the folded domain for another partner, shown as an orange block (I), binds to protein partners and exposes the active site in the folded domain (II) or releases active sites in both the disordered domain and the folded domain for interaction with various partners (III).