Project description:Maternal inheritance of mitochondrial DNA (mtDNA) is highly conserved in metazoans. While many species eliminate paternal mtDNA during late sperm development to foster maternal inheritance, the regulatory mechanisms governing this process remain elusive. Through a large-scale genetic screen in Drosophila, we identified 47 mutant lines exhibiting substantial retention of mtDNA in mature sperm. We mapped one line to Poldip2, a gene predominantly expressed in the testis. Disruption of Poldip2 led to pronounced mtDNA retention in mature sperm and subsequent paternal transmission to progeny. Further investigation via imaging, biochemical analyses and ChIP assays revealed that POLDIP2 is a mitochondrial matrix protein capable of binding to mtDNA. Moreover, we uncovered that CLPX, a key component of the major mitochondrial protease, binds to POLDIP2 to co-regulate mtDNA elimination in Drosophila spermatids. This study shed light on the mechanisms underlying mtDNA removal during spermatogenesis, underscoring the pivotal role of this process in safeguarding maternal inheritance.
Project description:Whole-genome sequencing of two North American Drosophila melanogaster populations reveals genetic differentiation and positive selection
Project description:Maternal inheritance of mitochondrial DNA (mtDNA) is highly conserved in metazoans. While many species eliminate paternal mtDNA during late sperm development to foster maternal inheritance, the regulatory mechanisms governing this process remain elusive. Through a large-scale genetic screen in Drosophila, we identified 47 mutant lines exhibiting substantial retention of mtDNA in mature sperm. We mapped one line to Poldip2, a gene predominantly expressed in the testis. Disruption of Poldip2 led to pronounced mtDNA retention in mature sperm and subsequent paternal transmission to progeny. Further investigation via imaging, biochemical analyses and ChIP assays revealed that POLDIP2 is a mitochondrial matrix protein capable of binding to mtDNA. Moreover, we uncovered that CLPX, a key component of the major mitochondrial protease, binds to POLDIP2 to co-regulate mtDNA elimination in Drosophila spermatids. This study shed light on the mechanisms underlying mtDNA removal during spermatogenesis, underscoring the pivotal role of this process in safeguarding maternal inheritance.
Project description:Food consumption is critical for animal survival and reproduction. The biomedical and economic consequences of metabolic diseases arising from excessive food intake, however, are a burden for human society. While the role of neuroendocrine feedback loops, food sensing modalities, and physiological state in regulating food intake are increasingly well understood, other genetic mechanisms remain elusive. Here, we applied ten generations of artificial selection for high and low food consumption in replicate populations of Drosophila melanogaster. The phenotypic response to selection was highly asymmetric, with efficient selection and an average realized heritability of 0.15 in the lines selected for high food consumption. To further nominate candidate genes contributing to response to selection for feeding behavior, we evaluated differences in genome wide gene expression between the selection lines using whole-fly RNA sequencing. We identified 1,631 differentially expressed genes in the analysis pooled across sexes, and 1,267 (2,321) differentially expressed genes in females (males).