| Evolution of metazoan 5S rRNA sequences was analyzed through base composition and types, location and frequency of clustered bases. Characters from sequences of protostomes did not show regular trends as compared with paleontology dating or organism complexity. Trends of increasing G and C, stronger in G clusters, and decreasing A and U, were detected in deuterostomes, in parallel with evolution of complexity. The multifunctional domain 71-104 was highlighted among conserved stretches. Clusters of C were typical of helices. Those of G were longer, extending from helices into loops or related to bulges, which is suggestive of functional significance. Deuterostomian trends were installed early in the lineage and reached full development in aquatic organisms,... |
