Multisite Threonine Phosphorylation in the SPT5 C‑Terminal Region 1 Enables Sequence-Dependent Regulation without Global Structural Remodeling
This work establishes that multisite phosphorylation of the SPT5 CTR1 domain modulates a heterogeneous interaction landscape shaped by sequence context, and emphasizes the nontrivial difference between serine and threonine phosphorylation as a mechanism to regulate disordered protein structure–function relationships.