| Autor: |
SIBSON, D. R, HUGHES, S. G., BRYANT, J. A., FITCHETT, P. N. |
| Zdroj: |
Journal of Experimental Botany; February 1991, Vol. 42 Issue: 2 p243-243, 1p |
| Abstrakt: |
The amphidiploid (AACC) nuclear genome of Brassica napus (oil-seed rape) contains c. 5 ? 105 copies of a simple, highly repetitive DNA element; each repeat is 176 or 177 base pairs long and is defined by Hind III cutting sites. The diploid (AA) Brassica campestris (turnip) possesses a very similar repetitive DNA, the consensus sequence of which does not differ from that in B. napus. The 176/177 bp unit consists of three 59 bp sub-units, defined by vestigial EcoRII sites. Analysis of the distribution of variants from consensus in adjacent and non-adjacent units provides evidence for homogenization of sequences by the fixation of independent mutations and for tandem duplication of units. Within units, there is also evidence for inversion and tandem duplication of short (5–8 bp) motifs. Previously published data show that 176/177 base pair repetitive DNA elements, defined by Hind III cutting sites, are also present in Sinapis and Raphanus. There is a sequence homology between Brassica and Sinapis, and between Brassica and Raphanus, of 75%. Sequence homology between Raphanus and Sinapis is 73%. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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