A novel class of miniature inverted repeat transposable elements (MITEs) that contain hitchhiking (GTCY)n microsatellites


Brad S. Coates, USDA-ARS, Corn Insects & Crop Genetics Research, 113 Genetics Lab, Iowa State University, Ames, IA 50010, USA. Tel.: + 1 515 294 0668; fax: + 1 515 294 2265; e-mail: brad.coates@ars.udsa.gov


The movement of miniature inverted repeat transposable elements (MITEs) modifies genome structure and function. We describe the microsatellite-associated interspersed nuclear element 2 (MINE-2), that integrates at consensus WTTTT target sites, creates dinucleotide TT target site duplications (TSDs), and forms predicted MITE-like secondary structures; a 5′ subterminal inverted repeat (SIR; AGGGTTCCGTAG) that is partially complementary to a 5′ inverted repeat (IR; ACGAAGCCCT) and 3′-SIRs (TTACGGAACCCT). A (GTCY)n microsatellite is hitchhiking downstream of conserved 5′MINE-2 secondary structures, causing flanking sequence similarity amongst mobile microsatellite loci. Transfection of insect cell lines indicates that MITE-like secondary structures are sufficient to mediate genome integration, and provides insight into the transposition mechanism used by MINE-2s.