English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Heterozygosity for a deficiency for the entire zeste-white region of the X chromosome of Drosophila melanogaster females causes both reduced recombination and increased nondisjunction. The location of the dosage-sensitive sites responsible for these two meiotic defects has been studied by use of a set of deficiencies that subdivide the region. Recombination is reduced when the zw7-zwll region is present in one dose, while nondisjunction is increased only if the doses of both the zw8-zwl0 and zwb-zwll segments are reduced. Examination of truns heterozygotes of two deficiencies explicitly demonstrates the compound nature of the meiotic dose effect and further delimits the location of the proximal disjunctional site to the zwl2-zwll interval. In inversion/deficiency heterozygotes, reduced dose ofthe zw8-zwl0 region alone, without reduced dose of the proximal site, yields increased nondisjunction, suggesting that the proximal element that affects disjunction is the same as that which affects recombination. Thus, the zeste-white region contains at least two dosagesensitive loci that affect meiosis: reduced dosage of one locus, in the zw7-zwfl interval, causes reduced recombination; reduced dose of another, in the zw8-zw10 region, increases the probability that nonexchange chromosomes will nondisjoin. Aslight effect on the regional distribution of exchange may also be a property of the zw8-zwlO region locus, but could be an effect of yet another locus or of structural heterozygosity. The implications of these results for understanding meiotic control and the prospects for further analysis of the structure of the zeste-white interval are considered.

THE MEIOTIC EFFECTS OF A DEFICIENCY IN DROSOPHILA MELANOGASTER: IDENTIFICATION OF TWO DOSAGE-SENSITIVE SITES