Figure 9.

Comparative ultrastructure and localization of NBs. NBs in untreated HeLa cells, except for p62 bodies and fused PML/p62 bodies which formed readily only after LMB treatment, are depicted. Schematic representation illustrates that only INBs and CNoBs are found within the nucleolus and that hybrid bodies are found only between p62 and PML bodies. The frames exemplify the variable sizes and structures of NBs labeled with CRM1 (CNoB), SUMO-2/3 (INB), PML (PML body), PML (15 nm)/p62 (10 nm) (Hybrid body), p62/SQSTM1 (p62 body) and PSPC1 (Paraspeckle). The CB is unlabelled to highlight its characteristic large coiled threads. Their presumed (?) or reported functions are mentioned below each frame. TFs = transcription factors; Ubi⁺ proteins = ubiquitinated proteins. Scale bars: 100 nm.