Eukaryotic genomes contain a large proportion of repetitive DNA sequences, mostly transposable elements (TEs) and tandem repeats. These repetitive sequences often colonize specific chromosomal (Y or W chromosomes, B chromosomes) or subchromosomal (telomeres, centromeres) niches. Sex chromosomes, especially non-recombining regions of the Y chromosome, are subject to different evolutionary forces compared with autosomes. In non-recombining regions of the Y chromosome repetitive DNA sequences are accumulated, representing a dominant and early process forming the Y chromosome, probably before genes start to degenerate. Here we review the occurrence and role of repetitive DNA in Y chromosome evolution in various species with a focus on dioecious plants. We also discuss the potential link between recombination and transposition in shaping genomes.
Bibliographical noteFunding Information:
The authors thank Professor Andrew Leitch and Dr Jiri Macas for their comments on the manuscript and Bc. Julia Svoboda for revision of the manuscript. This research was supported by the LC06004 grant from Ministry of Education and grants no. AV0Z50040507 and AV0Z50040702 from the Academy of Sciences of the Czech Republic.
- Repetitive sequences
- Sex chromosomes
- Tandem repeats (satellites)
- Transposable elements