A helitron-like transposon superfamily from lepidoptera disrupts (GAAA)(n) microsatellites and is responsible for flanking sequence similarity within a microsatellite family.
Transposable elements (TEs) are mobile DNA regions that alter host genome structure and gene expression. A novel 588 bp non-autonomous high copy number TE in the Ostrinia nubilalis genome has features in common with miniature inverted-repeat transposable elements (MITEs): high A + T content (62.3%), lack of internal protein coding sequence, and secondary structure consisting of subterminal inverted repeats (SIRs). The O. nubilalis TE has inserted at (GAAA)(n) microsatellite loci, and was named the microsatellite-associated interspersed nuclear element (MINE-1). Non-autonomous MINE-1 superfamily members also were identified downstream of (GAAA)(n) microsatellites within Bombyx mori and Pectinophora gossypiella genomes. Of 316 (GAAA)(n) microsatellites from the B. mori whole genome sequence, 201 (63.6%) have associated autonomous or non-autonomous MINE-1 elements. Autonomous B. mori MINE-1s a encode a helicase and endonuclease domain RepHel-like protein (BMHELp1) indicating their classification as Helitron-like transposons and were renamed Helitron1_BM. Transposition of MINE-1 members in Lepidoptera has resulted in the disruption of (GAAA)(n) microsatellite loci, has impacted the application of microsatellite-based genetic markers, and suggests genome sequence that flanks TT/AA dinucleotides may be required for target site recognition by RepHel endonuclease domains.
Coates
Brad S
BS
USDA-ARS, Iowa State University, Ames, 50011, USA. brad.coates@ars.usda.gov
Sumerford
Douglas V
DV
Hellmich
Richard L
RL
Lewis
Leslie C
LC
D024509:3' Flanking Region / Q000235:genetics; D024506:5' Flanking Region / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D020134:Catalytic Domain; D003001:Cloning, Molecular; D004251:DNA Transposable Elements / Q000235:genetics*; D007915:Lepidoptera / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D016254:Mutagenesis, Insertional / Q000235:genetics* / Q000502:physiology; D009690:Nucleic Acid Conformation; D012689:Sequence Homology, Nucleic Acid; D013379:Substrate Specificity
D004251:DNA Transposable Elements