SPP 2349 - Teilprojekt: GEvol-Defense - Evolution of novel cellular defences via horizontal gene transfer in leaf beetles

Basic data for this project

Description

The evolutionary success of insects lies in their versatile defense systems against environmental pertubations and high reproduction rates. Insects' cellular defense is mostly mediated by hemocytes, a group of cells that are important for both immunity and reproduction. Although evidence suggests rapid evolution of hemocyte functions, the underlying genomic mechanisms remain elusive. Our recent Colorado potato beetles (CPB, Leptinotarsa decemlineata) expression atlas showed that three recently duplicated genes, which originated from horizontal gene transfer from bacterial at the basal branch of leave beetles, are specifically expressed in CPB hemocytes, suggesting that the recruitment of horizontal gene transfer (HGT) can contribute to the evolution of novel defenses in the beetles. Here, we aim to illustrate how these genes evolve and contribute to novel cellular defenses and development in leaf beetles. We will first perform single-cell RNA- and ATAC -sequencing to identify the regulatory mechanisms of cellular - expression of the HGT genes. Then, we will reveal the function of the horizontally transferred genes via knock-down their expression in CPB and heterologous expression in Drosophila. Third, we will reconstruct the evolutionary history of the function and regulation of the horizontally transferred genes by integrating comparative genomics and single-cell sequencing among four beetle species. We aim to identify the key functional and expression motifs that contributed to the novel hemocyte functions in leaf beetles. By integrating state-of-the-art genomic and molecular tools, this project will provide new insights into how horizontally transferred genes can be recruited into existing signaling networks and contribute to evolutionary novelties in insects.