Biology of Sperm and Mitochondrial-Nuclear Interactions
Previous and Current Research
Our lab combines molecular, microscopy and evolutionary methods and concepts in three areas.
Mitochondria contribute to the phenotype, either alone or because the crosstalk with the nucleus is disturbed. In Mito-nuclear interactions, we use Drosophila lines to disentangle mitochondrial, nuclear, and mito-nuclear interaction effects on the phenotype. The observation that offspring with co-evolved mito-nuclear combinations often perform superior to those carrying mismatched mito-nuclear combinations has important implications for the study of mitochondrial diseases and the clinical application of the so-called three-parent-baby technology of nuclear transfer.
Sperm dysfunction is the single most important known contributor to infertility (which itself concerns one in six couples in the western world). Evolutionary and medical research has independently revealed that genetic causes only explain about 15% of sperm dysfunction cases. This is why in Male infertility and sperm biology we study how various environments (sexually transmitted microbes, oxygen radicals, hypoxia) affect sperm function. We developed methods to measure sperm metabolic rate and sperm ROS production rate in the same sample (see figure below) and apply quantitative genetics and experimental evolution to quantify genetic responses. Our results showing that some sperm traits have no heritability but phenotypic plasticity and vary with sperm age challenge sperm fucntion tests used in clincial settings and challenge the idea that sperm competition drives evolutionary change.
Our third interest, Cuticle Biology, revolves around the molecular biology and material properties of the arthropod cuticle. We study how chitin acts as an essential scaffold element to contribute to the correct stratification of the cuticle, examines genes involved in Drosophila embryogenesis and demonstrated a self-sealing and anti-wounding function of the super-elastic protein resilin in bedbugs.
Future Projects and Goals
We aim to combine microscopy techniques with spectrometric methods and evolutionary tools in Drosophila melanogaster to examine sperm metabolism in vivo. We hope to tackle the role that mitochondria might play in the environmental modifications of sperm. We seek to understand to what extent mitochondrial diseases are caused by interactions between the nucleus and the mitochondria.
Methodological and Technical Expertise
- Advanced statistical modelling
- Quantitative genetics
- Developmental biology
Byri S, … Moussian B, Uv A, Luschnig S
The triple-repeat protein anakonda controls epithelial tricellular junction formation in Drosophila.
Devel Cell 10.1016/j.devcel.2015.03.023 (2015)
Moussian B et al.
Deciphering the genetic programme triggering timely and spatially-regulated chitin deposition.
PLoS Genetics 24: 11:e1004939 (2015)
Michels J, Gorb S, Reinhardt K.
Reduction of female copulatory damage by resilin represents evidence for tolerance in sexual conflict.
J Roy Soc Interface 12: 20141107 (2015)
Reinhardt K, Dowling DK, Morrow EDH
Mitochondria Replacement, Evolution, and the Clinic.
Science 341: 1345–6 (2013)
Reinhardt K, Ribou A-C
Females become infertile as the stored sperm’s oxygen radicals increase.
Sci Rep 3:2888 (2013)