Münster Drosophila Mini-Symposium

Motile ciliopathies are a heterogeneous group of genetic disorders caused by dysfunction of motile cilia in various organ systems. A common motile ciliopathy is the multisystem disorder primary ciliary dyskinesia, characterized by recurrent respiratory symptoms. Motile ciliopathies also play an important role in the etiology of male infertility, as sperm flagella defects often occur in combination with structural and functional abnormalities of other types of motile cilia. However, to date, a genetic cause of male infertility can only be found in 4.3% of cases leaving a
large proportion of diagnoses incomplete. In addition, 20-30% of PCD cases are still genetically unsolved. Therefore, it is necessary to further elucidate the genetic landscape and functionally characterize genetic defects associated with motile ciliopathies and male infertility. The fruit fly Drosophila melanogaster is recently emerging as a model organism for motile cilia biology. Although in Drososphila only two specialized cell types carry motile cilia: the sperm flagellum with a 9+2 axoneme and the ciliated dendrite of auditory/proprioceptive (chordotonal, Ch) neurons with a 9+0 axoneme, it has been found that molecules essential for cilia motility are well conserved. They present with restricted cell type-specific expression patterns and phenotypes. These differences may reflect specialized functions for motility in the two cilia types. Furthermore, around 61% of Drosophila genes are conserved in humans and 59% of human disease genes are homologous in the fly. As Drosophila represents a suitable, ethical and high-throughput alternative for testing and functional characterization of candidate genes, we here propose an RNAi silencing approach of candidate genes in the fruit fly to improve our understanding of the underlying genetic causes of motile ciliopathies, including male infertility.