I have not found a good definition of interchromatin granule clusters. Beginning concerns are: 1) the clusters have non membrane bounds, this presents a perfect opportunity for misconceptions. Here are some predictions:

1. inerchromatin granule clusters behave like lipid droplets (begin perhaps irregularly shaped but finally ends up roundish.
2. Variations in the granularity of interchromatin granule clusters, coarse, fine, symmetrically placed, numerous and also scarce, large and small.
3. Numerous protein-protein- protein-RNA interactions
4. Abundance of different proteins, at various times, some of which can form oligomers such as SPOP (which can make 25-mers) and the degree of oligomerization may depend upon the concentration of protein in the interchromatin granule cluster.
5. The cluster itself has boundaries that are clearly demarkated regardless of the number and size of structures with those boundaries.
6. SPOP dimers help organize higher order structures within the interchromatin granules clusters and other places