Conservation of segmental variants of satellite DNA of Mus musculus in a related species: Mus spretus
Abstract
There has been much recent discussion on the biological function of the highly-repetitive DNAs (satellite DNAs) of higher organisms1-9, that have several curious features of sequence organization. First, some satellite sequences show a high degree of conservation between related species10-15. Second, there is independent evolution of `type B' segments (sequence variants) within a block of tandem repeats16. The majority of the Mus musculus satellite DNA can be cut to produce a type A pattern with either EcoRII or AvaII (ref. 8). However, digestion of M. musculus satellite with other enzymes produces a limit series of fragments from only part of the total satellite (type B segment)16. To understand the significance of the segmental sequence variants, it is necessary to characterize their distribution between individual chromosomes of a genome18 and between closely related genomes. We report here the distribution of type A and B patterns in the two closely related species, Mus musculus and Mus spretus19,20. The data show that the genome of M. spretus contains homologous sequences that are organized into the same type B segments as M. musculus, except for one type B segment that is under-represented in M. spretus. From a knowledge of the genetic distance and hybrid fertility between these species19,20, we are able to exclude one of the proposed biological roles for these particular genomic components.
- Publication:
-
Nature
- Pub Date:
- May 1980
- DOI:
- 10.1038/285047a0
- Bibcode:
- 1980Natur.285...47B