Hartl, Sarah J. Sweeney and Peter J. Knepler, both at the UA, and Bosco published their paper, "Condensin II Resolves Chromosomal Associations to Enable Anaphase I Segregation in Drosophila Male Meiosis," in the October 2008 issue of PLoS Genetics. Sweeney and Knepler were UA undergraduates when they conducted the research.
The National Institutes of Health and the National Science Foundation funded the research.
Learning how cells control chromosomes and how DNA is transcribed will lead to better understanding of how an organism's DNA affects the organism's final form.
Scientists have known for about 50 years that when chromosomes are in direct contact, the transcription machinery can choose to transcribe either the gene from the mother or the gene from the father.
Many researchers investigated how the specific genes were brought close together so that process, known as transvection, could happen.
Bosco wondered, what if the chromosomes stayed stuck together?
To find something that separated chromosomes, he looked for female fruit flies that were sterile because chromosomes in their eggs had stuck together.
Once he had those fruit flies, Hartl isolated the gene that kept the chromosomes from coming apart. He found that the gene coded for condensin II, indicating that the sterile flies couldn't make condensin II.
To be able to watch how condensin II affects chromosomes, the researchers used the salivary glands from normal Drosophila melanogaster fruit flies. Fruit fly salivary glands are unusual, because they have many copies of the same chromosome coiled together like a rope.
Hartl said, "You can actually see chromosomes, because the cells are so huge and the chromosomes are so huge."
The team inserted an additional gene into the chromosomes that would turn the condensin II-producing gene off at 77 F (21 C) and on at
|Contact: Mari N. Jensen|
University of Arizona