Biology subjects

Lu, K. L.

Publications and source records attributed to Lu, K. L..

2 recordsLinked to original sources

bioRxiv2017

Transgenerational dynamics of rDNA copy number in Drosophila male germline stem cells

rDNA loci, composed of hundreds of tandemly duplicated arrays of rRNA genes, are known to be among the most unstable genetic elements due to their repetitive nature. rDNA instability underlies aging (replicative senescence) in yeast cells, however, its contribution to the aging of multicellular organisms is poorly understood. In this study, we investigate the dynamics of rDNA loci during aging in the Drosophila male germline stem cell (GSC) lineage, and show that rDNA copy number decreases during aging. Our study further reveals that this age-dependent decrease in rDNA copy number is heritable from generation to generation, yet GSCs in animals that inherit reduced rDNA copy number are capable of recovering normal rDNA copy number. Based on these findings, we propose that rDNA loci are dynamic genetic elements, where rDNA copy number changes dynamically yet is maintained through a recovery mechanism in the germline.

developmental biology↗

bioRxiv2017

Germ cell connectivity enhances cell death in response to DNA damage in Drosophila testis

Two broadly known characteristics of germ cells in many organisms are their development as a cyst of interconnected cells and their high sensitivity to DNA damage. Here we provide evidence that these characteristics are linked, and that interconnectivity is a mechanism that confers to the Drosophila testis a high sensitivity to DNA damage. We show that all germ cells within a cyst die simultaneously even when only a subset of them exhibit detectable DNA damage. Compromising connectivity results in cysts in which only a subset of germ cells die upon DNA damage, lowering overall germ cell death. Our data indicate that a death-promoting signal is shared through the intercellular connections of germ cells. Taken together, we propose that intercellular connectivity is a mechanism that uniquely increases the sensitivity of the germline to DNA damage, thereby protecting the integrity of gamete genomes that are passed on to the next generation.

developmental biology↗