These analogues of "PML" objects are made up mostly of p80 coilin.
Andrade et al produced a seminal 1991 study in which they found these objects, and isolated and cloned an 80-kilodalton protein that makes up much of their structure. These objects are the site of assembly of complexes that combine with pre-RNA to form the splicesome. In that function, they aid in the post-transcriptional modification of RNA by assembling (**) SnRNPs ("snurps"). These analogues of "PML" objects are made up mostly of p80 coilin. They were first called nucleolar accessory objects, since they are found only in the cell (*) nucleus. For 10 points, name these spherical sub-organelles found in embryonic, tumor, and neuronal cells, certain coiled "bodies" named after a Spanish biologist. 
Andrade et al produced a seminal 1991 study in which they found these objects, and isolated and cloned an 80-kilodalton protein that makes up much of their structure.
Cajal bodies