Linked Life Data

6417536

Source:http://linkedlifedata.com/resource/pubmed/id/6417536

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1984-1-26
pubmed:abstractText
Selection responses of the laboratory stock Berlin wild (+60, +K) of Drosophila melanogaster to the mutagenic effects of high, accumulated exposures of X-rays were studied in several sub-populations with long irradiation histories. Interest was focussed on adaptive adjustments of mutation rates. In samples from the populations, radiosensitivities of immature oocytes were tested, by using dominant lethals (A), X-chromosome losses (B) and sex-linked recessive lethals (C) as end-points of genetic radiation damage. Populations RO II and RO V are similar to the previously studied population RO I and were exposed to 2100 R/generation, delivered to oocyte stages 6-14, mature sperm, and spermatids. RO II (first tests after 160 generations) is radioresistant relative to +60 (control). The resistance was characterized by dose-reduction factors (DRFs) of 1.72 (with respect to end-points A, B) and 1.53 (C), and these were similar to those previously obtained for RO I. The resistance of RO II was inherited semidominantly as was that of RO I, and the radiosensitivity of the hybrids RO I/RO II was similar to that of RO I and RO II with respect to end-points A and B. RO V did not become resistant within 25 generations of irradiation history (A). Populations RO III (6000 R/generation) and RO IV (7000 R/generation) have histories of irradiations given to oogonia and spermatogonia. Radiosensitivities of immature oocytes of RO III did not differ from those of +K after 55 generations, but after 105 and 135 generations of irradiation history, DRFs of 1.2 (A) and 1.44 (B) were observed. RO IV was characterized in generations 55-135 by DRFs of 1.31 (A) and 1.72 (B). Selection for relative radioresistance of immature oocytes was found (1) to be reproducible (RO II-RO IV), (2) not to require genetic pre-adaptation (RO V), and (3) to be, in part, also achieved by 'indirect' selection (RO III, RO IV). It is concluded that mutation rates in populations are selectively adjusted to evolutionary requirements.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0027-5107
pubmed:author
pubmed:issnType
Print
pubmed:volume
111
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
325-40
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Investigations on radiosensitive and radioresistant populations of Drosophila melanogaster. XVI. Adaptation to the mutagenic effects of X-rays in several experimental populations with irradiation histories.
pubmed:publicationType
Journal Article, Comparative Study