J Syst Evol ›› 2014, Vol. 52 ›› Issue (6): 743-749.DOI: 10.1111/jse.12113

• Reviews & Research Articles • Previous Articles     Next Articles

Comparative analysis of Stowaway-like miniature inverted repeat transposable elements in wheat group 7 chromosomes: Abundance, composition, and evolution

1Yun-Ze LU, 1Le WANG, 1Hong YUE, 1Meng-Xing WANG, 1Ping-Chuan DENG, 2David EDWARDS, 1Song WEINING*   

  1. 1(State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy and Yangling Branch of China Wheat Improvement Center, Northwest A&F University, Yangling, Shaanxi, China)
    2(School of Agriculture and Food Sciences and Australian Centre for Plant Functional Genomics, University of Queensland, Brisbane, Australia) These authors contributed equally to this work.
  • Received:2014-02-15 Published:2014-11-13

Abstract: Miniature inverted repeat transposable elements (MITEs) are the most ubiquitous transposable elements in eukaryotic genomes; they play a prominent role in sequence divergence and genome evolution. There are many well-characterized Stowaway-like MITE families in wheat, but their distribution, abundance, and composition at the chromosome level are still not well understood. In this study, we systematically investigated the Stowaway-like MITEs in wheat group 7 chromosomes based on the survey sequences of isolated wheat chromosomes, to compare them at the chromosome level and to reveal their evolutionary role on wheat polyploidization. In summary, 2026 MITEs were identified, of which 587, 714, and 725 were distributed on 7A, 7B, and 7D chromosomes, respectively. There are more MITEs present on 7D, compared to 7A and 7B, suggesting A and B subgenomes eliminated some repetitive elements during two hybridization processes. Furthermore, some chromosome/arm-specific MITEs were also identified, providing information on the function and evolution of MITEs in wheat genomes. The sequence diversity of the MITE insertions was also investigated. This study for the first time investigated the abundance and composition of MITEs at the chromosome level, which will be beneficial to improve our understanding of the distribution of wheat MITEs and their evolutionary role in polyploidization.

Key words: homoeologous chromosomes, repetitive elements, Stowaway-like MITEs, survey sequences, wheat.