Figure 9. Schematic illustrating the potential molecular mechanisms underlying the formation of stress-inducible RNP granules.
(A) RNA-protein (RNP) granule formation as a two-step assembly process. In the first step, RNAs and RNA-binding proteins associate to form large RNP complexes (nucleation step). In the second step, these RNP complexes coalesce into larger compartments through additional RNA-mediated interactions, but primarily through PLD-mediated weak binding events (coalescence step). PLDs are indicated in red and RBDs indicated in blue. (B) Stress-inducible RNP granules have different compositions, which affect their dynamic and material properties. The presumed average interaction strength is indicated in red. Weak interactions increase the vulnerability to hexanediol. An aggregation-prone stress sensor domain (SD) is indicated in dark green.