Abstract
The complete nucleotide of mitochondrial DNA of a sea urchin Mesocentrotus nudus was determined for the first time. It is 15,709 bp in length, containing 2 rRNA, 22 tRNA and 13 protein-coding genes generally found in other echinoderm species. The gene order and structure of the genome are identical to those of other Strongylocentrotidae species. The genome was composed of 29.3% A, 23.4% C, 29.5% T and 17.8% G, showing a slight AT bias (58.8%). The G is the least used base and markedly lower at the third codon position (12.74%). Twelve of the 13 mitochondrial protein-coding genes use ATG as their start codon while the ATP8 gene starts with GTG. The control region is 125 bp in length and contains a G-stretch of 19 nucleotides, a typical DNA structure of the echinoid mitochondrial genomes.
Declaration of interest : This study was supported by the project titled “Construction of Ocean Research Stations and their Application Studies” and also by the grant “Marine biodiversity Conservation” funded by the Ministry of Land, Transport and Maritime Affairs. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.