| Title |
Control of DNA replication and spatial distribution of defined DNA sequences in salivary gland cells of Drosophila melanogaster
|
|---|---|
| Published in |
Chromosoma, January 1985
|
| DOI | 10.1007/bf00328223 |
| Pubmed ID | |
| Authors |
Martin P. Hammond, Charles D. Laird |
| Abstract |
In dividing cells, each sequence replicates exactly once in each S-phase, but in cells with polytene chromosomes, some sequences may replicate more than once or fail to replicate during S-phase. Because of this differential replication, the control of replication in polytene cells must have some unusual features. Dennhöfer (1982a) has recently concluded that the total DNA content of the polytene cells of Drosophila salivary glands exactly doubles in each S-phase. This observation, along with previous studies demonstrating satellite underreplication in salivary gland cells, led us to consider the hypothesis that there is a "doubling of DNA" mechanism for the control of DNA replication in polytene cells. With this mechanism, a doubling of DNA content, rather than the replication of each sequence, would signal the end of a cycle of DNA replication. To test this hypothesis, we have reinvestigated the replication of several sequences (satellite, ribosomal, histone and telomere) in salivary gland cells using quantitative in situ hybridization. We find that underreplication of some sequences does occur. In addition we have repeated Dennhöfer's cytophotometric and labeling studies. In contrast to Dennhöfer, we find that the total DNA contents of nonreplicating nuclei do reflect this partial replication, in accord with Rudkin's (1969) result. We conclude that DNA replication in polytene cells is controlled by modifications of the mechanism operating in dividing cells, where control is sequence autonomous, and not by a "doubling of DNA" mechanism. In situ hybridization to unbroken salivary gland nuclei reveals the distribution of specific sequences. As expected, satellite, histone and 5S sequences are usually in a single cluster.(ABSTRACT TRUNCATED AT 250 WORDS) |
Mendeley readers
The data shown below were compiled from readership statistics for 26 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 26 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 11 | 42% |
| Professor | 5 | 19% |
| Student > Master | 3 | 12% |
| Professor > Associate Professor | 2 | 8% |
| Researcher | 1 | 4% |
| Other | 1 | 4% |
| Unknown | 3 | 12% |
| Readers by discipline | Count | As % |
|---|---|---|
| Biochemistry, Genetics and Molecular Biology | 12 | 46% |
| Agricultural and Biological Sciences | 7 | 27% |
| Immunology and Microbiology | 1 | 4% |
| Unknown | 6 | 23% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 22 May 2020.
All research outputs
#8,882,501
of 26,017,215 outputs
Outputs from Chromosoma
#213
of 805 outputs
Outputs of similar age
#7,600
of 39,714 outputs
Outputs of similar age from Chromosoma
#2
of 5 outputs
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