28S ribosomal RNA is the structural ribosomal RNA (rRNA) for the large component, or large subunit (LSU) of eukaryotic cytoplasmic ribosomes, and thus one of the basic components of all eukaryotic cells. It is the eukaryotic nuclear homologue of the prokaryotic 23S and mitochondrial 16S ribosomal RNAs.
28S ribosomal RNA Wikipedia
The genes coding for 28S rRNA are referred to as 28S rDNA. The comparison of the sequences from these genes are sometimes used in molecular analysis to construct phylogenetic trees, for example in Protists, Fungi, Insects, Tardigrades, and Vertebrates.
Several databases provide alignments and annotations of LSU rRNA sequences for comparative purposes:RDP, the Ribosomal Database Project;
SILVA, a ribosomal RNA gene database project.