The Complete Mitochondrial Genome of the Hagfish Myxine glutinosa: Unique Features of the Control Region

Abstract

The complete sequence of the mitochondrial DNA of the hagfish Myxine glutinosa has been determined. The hagfish mtDNA (18,909 bp) is the longest vertebrate mtDNA determined so far. The gene arrangement conforms to the consensus vertebrate type and differs from that of lampreys. The exceptionally long (3628-bp) control region of the hagfish contains the typical conserved elements found in other vertebrate mtDNAs but is characterized by a large number of putative hairpins, which can potentially fold into a highly compact secondary structure that appears to be unique to hagfish. The comparison of the mtDNAs of two M. glutinosa specimens, excluding the control region, shows a 0.6% divergence at the nucleotide level as a sample of intraspecies polymorphism.

Complete Mitochondrial DNA of the Hagfish, Eptatretus burgeri: The Comparative Analysis of Mitochondrial DNA Sequences Strongly Supports the Cyclostome Monophyly

“…The mtDNA of Eptatretus burgeri was shorter than that of the other hagfish already determined, Myxine glutinosa (18909 bp) (Delarbre et al, 2001; accession number: AJ404477) due to the size of the control region of the latter (3628 bp). Excluding the control region, the lengths of the two mtDNAs were quite similar: 15310 and 15281 bp for Eptatretus and Myxine, respectively.…”

“…The data set used for phylogenetic analyses is composed of 13 taxa: Paracentrotus lividus (Cantatore et al, 1989), Asterina pectinifera (Asakawa et al, 1995), Balanoglossus carnosus (Castresana et al, 1998), Branchiostoma lanceolatum , Branchiostoma floridae (Boore et al, 1999), Myxine glutinosa (Delarbre et al, 2001), Lampetra fluviatilis (Delarbre et al, 2000), Petromyzon marinus (Lee and Kocher, 1995), Scyliorhinus canicula , Mustelus manazo (Cao et al, 1998), Cyprinus carpio (Chang et al, 1994), Oncorhynchus mykiss (Zardoya et al, 1995), and Eptatretus burgeri (present paper). The 13 protein-coding sequences of the mtDNAs were first aligned manually following translation of the nucleotide sequences using the mitochondrial genetic code specific for each taxon.…”

“…However, our data set did not allow an unambiguous conclusion, presumably because of too few cyclostome sequences. Since then, the nucleotide sequence of the mtDNA of another specimen of the hagfish, Myxine glutinosa (Delarbre et al, 2001), and of another hagfish, Eptatretus burgeri (present paper), have been determined. We have used this extended data set, enriched in mtDNA sequences obtained from cyclostomes, to approach the issue of basal relationships among the vertebrates.…”

Ancient Phylogenetic Separation between Pacific and Atlantic Cephalochordates as Revealed by Mitochondrial Genome Analysis

“…petra pairs for which the sequences were available in public databases (Lee and Kocher, 1995;Rasmussen et al, 1998;Delarbre et al, 2000;Delarbre et al, 2001;Delarbre et al, 2002). The average Ks for the Petromyzon-Lampetra pair was 1.19 (SD, 0.57; n=13; Supplemental Table S1, http://dx.…”

Circadian Rhythms in Locomotor Activity of the Hagfish, Eptatretus burgeri VI. The Effects of Cutting the Spinal Cord

“…To reconstruct a robust phylogenetic tree among these closely related species, highly diverged DNA sequences will have to be identified. As an example of a recent promising advance in this field, complete mitochondrial sequences have been published for two hagfish species, E. burgeri and M. glutinosa (Delarbre et al, 2001(Delarbre et al, , 2002. In addition, more than 20,000 expressed sequence tags (ESTs) have been collected (Suzuki et al, 2004).…”