Figure 4.

Spindly autoinhibition involves a direct interaction between N- and C-terminal regions. (A) Analytical SEC elution profile and SDS-PAGE analysis for interaction assays between the Spindly N-terminal and C-terminal domains. Spindly^1–250 (red, dashed) interacts with Spindly^250–605 (alone: purple, dashed; complex: red, continuous), but not with Spindly^{250–275_307–605} (alone: green, dashed; complex: green, continuous). Spindly^51–250 (blue, dashed) does not interact with Spindly^250–605 (complex: blue, continuous). Concentration of all fragments: 10 µM. (B) schematic representation of Spindly constructs referred to in C–E. (C) Mass photometry results for the constructs in B. (D) Data table from hydrodynamic and mass photometry results in C and D. The Stokes’ radius and frictional ratio were estimated from the AUC-measured sedimentation coefficient and from the theoretical molecular weights (MW). (E) AUC results for the constructs in B. The smaller sedimentation coefficient indicates higher drag, which is caused by an increased Stokes’ radius. Molecular weights are in kD. Source data are available for this figure: SourceData F4.