Nonrandom sister chromatid segregation mediates rDNA copy number maintenance in <i>Drosophila</i>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35895823.
- Also identified by DOI 10.1126/sciadv.abo4443 and PMC identifier 9328678.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Although considered to be exact copies of each other, sister chromatids can segregate nonrandomly in some cases. For example, sister chromatids of the X and Y chromosomes segregate nonrandomly during asymmetric division of male germline stem cells (GSCs) in <i>Drosophila melanogaster</i>. Here, we demonstrate that the ribosomal DNA (rDNA) loci, which are located on the X and Y chromosomes, and an rDNA binding protein Indra are required for nonrandom sister chromatid segregation (NRSS). We provide the evidence that NRSS, following unequal sister chromatid exchange, is a mechanism by which GSCs recover rDNA copy number, counteracting the spontaneous copy number loss that occurs during aging. Our study reveals an unexpected role for NRSS in maintaining germline immortality through maintenance of a vulnerable genomic element, rDNA.
Medical subject headings
- Chromatids
- Drosophila