Diversity and Evolution of Highly Repetitive DNA Sequences Constituting Chromosome Site-Specific Heterochromatin in Two Gerbillinae Species

Cytogenet Genome Res. 2023;163(1-2):42-51. doi: 10.1159/000533716. Epub 2023 Sep 14.


Constitutive heterochromatin, consisting of repetitive sequences, diverges very rapidly; therefore, its nucleotide sequences and chromosomal distributions are often largely different, even between closely related species. The chromosome C-banding patterns of two Gerbillinae species, Meriones unguiculatus and Gerbillus perpallidus, vary greatly, even though they belong to the same subfamily. To understand the evolution of C-positive heterochromatin in these species, we isolated highly repetitive sequences, determined their nucleotide sequences, and characterized them using chromosomal and filter hybridization. We obtained a centromeric repeat (MUN-HaeIII) and a chromosome 13-specific repeat (MUN-EcoRI) from M. unguiculatus. We also isolated a centromeric/pericentromeric repeat (GPE-MBD) and an interspersed-type repeat that was predominantly amplified in the X and Y chromosomes (GPE-EcoRI) from G. perpallidus. GPE-MBD was found to contain a 17-bp motif that is essential for binding to the centromere-associated protein CENP-B. This indicates that it may play a role in the formation of a specified structure and/or function of centromeres. The nucleotide sequences of the three sequence families, except GPE-EcoRI, were conserved only in Gerbillinae. GPE-EcoRI was derived from the long interspersed nuclear elements 1 retrotransposon and showed sequence homology throughout Muridae and Cricetidae species, indicating that the repeat sequence occurred at least in the common ancestor of Muridae and Cricetidae. Due to a lack of assembly data of highly repetitive sequences constituting heterochromatin in whole-genome sequences of vertebrate species published to date, the knowledge obtained in this study provides useful information for a deep understanding of the evolution of repetitive sequences in not only rodents but also in mammals.

Keywords: C-positive heterochromatin; CENP-B box; Centromeric/pericentromeric repetitive sequence; Concerted evolution; Long interspersed nuclear element 1 retrotransposon.

MeSH terms

  • Animals
  • Arvicolinae / genetics
  • Base Sequence
  • Centromere / genetics
  • Gerbillinae / genetics
  • Heterochromatin* / genetics
  • Humans
  • In Situ Hybridization, Fluorescence
  • Muridae / genetics
  • Repetitive Sequences, Nucleic Acid* / genetics


  • Heterochromatin