Nucleolar Dominance and Replicative Dominance in Drosophila Interspecific Hybrids
AUTOR(ES)
Goodrich-Young, C.
RESUMO
The replication of the rDNA complement of only one nucleolus organizer region during polytene chromosome formation (replicative dominance) was initially observed in Drosophila melanogaster. Here we demonstrate replicative dominance in Drosophila simulans and D. melanogaster/D. simulans interspecific hybrids. A second nucleolar phenomenon, nucleolar dominance, is observed in the diploid tissue of interspecific hybrids. In this case only one of two nucleolus organizer regions forms a nucleolus. However, reorganizations of the X chromosome heterochromatin which eliminate nucleolar dominance have no apparent effect on the expression of replicative dominance. These observations lead us to conclude that nucleolar dominance and replicative dominance are operationally separable functions influencing the rDNAs, and may be determined by differing regulatory events.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1203806Documentos Relacionados
- Studies on the Ribosomal RNA Cistrons in Interspecific Drosophila Hybrids. II. Heterochromatic Regions Mediating Nucleolar Dominance
- Differential transcription of ribosomal cistrons denoting nucleolar dominance in hybrids of Drosophila mulleri and Drosophila navojoa (mulleri complex, Repleta group)
- Nucleolar dominance in polytene cells of Drosophila
- On the mechanism of nucleolar dominance in mouse-human somatic cell hybrids.
- Meiotic Segregation and Male Recombination in Interspecific Hybrids of Drosophila