Mitochondrial genome architecture of the giant red sea urchin Mesocentrotus franciscanus (Strongylocentrotidae, Echinoida)

Abstract

© 2014 Informa UK Ltd. The complete mitochondrial genome of the Californian giant red sea urchin Mesocentrotus franciscanus has been determined. It has a length of 15,650 bp and contains the same 37 genes found in other metazoans (13 protein-coding genes, 22 tRNA genes, and two rRNA genes). Only five tRNA genes and the Nad6 gene are coded on the minus strand. There were 14 identified small intergene regions (2 to 24 bp) and a large non-coding region (125 bp) located between the tRNA-T and tRNA-P. The overall base composition of this genome is 29.8% A, 27.6% T, 29.7% C, and 17.5% G, with a slight A + T bias of 59.4%. The most frequent start codon is ATG (11 genes) whereas TAA is the most frequent stop codon (10 genes). Overall, gene arrangement pattern, gene content and genome organization is similar to other echinoids.