Abstract:
Miniature inverted-repeat transposable elements (MITEs), a group of short and non-autonomous DNA transposons, are widely present in eukaryotic genomes. The location of the MITEs distribution would affect the host. In this study, MITEs in 33 fish genomes of the agnatha, chondrichthyes, sarcopterygii and actinopterygii were predicted and analyzed using bioinformatics approach. Ultimately, 2433 MITEs were identified in 33 fish genomes. MITEs content in 33 fish genomes varied from 0.11% to 21.18%, and MITEs content was positively correlated with fish genome size. MITEs were classified into 10 super families according to different terminal inverted repeats (TIRs) and target site duplications (TSDs) with the largest family of TC1-Mariner superfamily. The insertion of MITEs into the fish genome was mainly happened 4 million years ago to now, and most species had an explosive expansion between 2—0.5 million years ago. A number of fish MITEs were inserted into or near the genes, which may play an important role in the regulation of gene expression.