| Gene order changes involving protein-encoding and ribosomal RNA genes are rare events within most animal phyla. |
| Almost all eukaryotes have multiple copies of their nuclear ribosomal RNA cistrons, arranged in a long tandem array. |
| Since these patterns are almost identical, it would appear that HMP associates with ribosomes or ribosomal proteins. |
| Among the archaebacterial-specific genes several ribosomal proteins, DNA metabolic enzymes, and proteasome subunits are prominent. |
| Because of their possibly unusual evolution, genes coding for ribosomal proteins were excluded from the analysis. |
| This finding is the first suggestion that multiple spliceosomal introns occur in ribosomal genes. |
