Mitochondrial gene arrangement of the horseshoe crab Limulus polyphemus L.: conservation of major features among arthropod classes.

摘要: Numerous complete mitochondrial DNA sequences have been determined for species within two arthropod groups, insects and crustaceans, but there are none a third, the chelicerates. Most gene arrangements reported crustaceans insect identical or nearly to that of Drosophila yakuba. Sequences across 36 boundaries in (mtDNA) representative chelicerate. Limulus polyphemus L., also reveal an arrangement like Only position tRNA(LEU)(UUR) differs; it is between genes tRNA(LEU)(CUN) ND1. This positioning found onychophorans, mollusks, annelids, not indicates tRNA(LEU)(CUN)-tRNA(LEU)(UUR)-ND1 was ancestral these as suggested earlier. There no differences relative protein-coding ribosomal RNA Drosophila, observed arthropods. The high degree similarity arthropods striking, since some taxa last shared common ancestor before Cambrian, contrasts with extensive mtDNA rearrangements occasionally other metazoan phyla (e.g., mollusks nematodes).