Comparative analysis of planarian regeneration

• Applicant: Dr. Jochen Rink
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology) ; Developmental Biology
• Term: from 2019 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 418095581

Planarian flatworms are famous for their regenerative abilities, but regeneration deficient species exist even in this group. Planarians therefore provide a unique opportunity to study the molecular and evolutionary underpinnings of regeneration. Our lab has established a unique live collection of >70 planarian species that cover the full range of regenerative abilities and wehave recently succeeded in generating the first high quality genome assembly of the model species S. mediterranea. As part of our comparative analysis of planarian regeneration, this project focuses on the genus "Polycelis". The comparatively small evolutionary distances between the well-regenerating species P. felina and P. nigra and and the regeneration-deficient speciesP. tenuis are ideal for comparative approaches. Specifically, we will generate high quality de novo genome assemblies of the three species and the marine outgroup species B. candida. Additionally, we will carry out RNAseq and ATACseq time courses of different amputation/wounding paradigms to characterize the species-specific transcriptional and gene regulatory responses to wounding. In conjunction with our increasingly detailed understanding of regenerative mechanisms in the model species S. mediterranea, the integration of all the data will define core modules of planarian regeneration, transcriptional changes inregeneration deficient species and ultimately the genomic regions that govern expression alterations. Our analysis will strategically focus on Wnt signaling components, as we find changes in this signaling pathway to be generally associated with planarian regeneration defects. Overall, these experiments will provide a first genomic perspective of planarian regeneration and mechanistic insights into the question why some worms regenerate, while others cannot.

• DFG Programme: Research Grants