A central question in biology is how complex forms have evolved. One common way for animals to become complex is through being built of repeated parts, like body segments, that can be changed independently. The largest group of segmented animals is the arthropods. Most arthropods make their segments by adding them from a posterior region called the "growth zone". A common set of genes has recently been hypothesized to control the growth zone in diverse arthropods. However, the cell processes that elongate the growth zone are elusive. Without understanding the cell processes that normally elongate the growth zone, it is impossible to explain the role of genes in controlling segmentation. This work will synthesize two approaches to understanding growth zone elongation and segmentation. First, direct measures of cell processes such as cell division, cell shape, cell motility and gene function will be made in three arthropod species, a crustacean and two insects. Then, these data will be fed into computational models of segment formation. Lab results will keep the computer models realistic while computer models will allow rapid exploration of relationships between genes and cell processes and thus inform new lab work. This project will be the first to bring computational modeling to a fine-grain analysis of arthropod sequential segmentation. The results will be important for studies of development and for synthetic biology. The proposed work is an international collaboration between 3 research labs with both unique and overlapping expertise. Undergraduates, graduate students, and post-docs will participate in multi-disciplinary training that synthesizes laboratory and computational approaches, fostering an integration of quantitative and experimental skills early in their careers. Importantly, students will also have the opportunity for international exchange between Israeli and US labs, through summer exchanges between the labs, and "live" exchange of ideas during regular web-based meetings. The outcomes of this work will also be shared with the public through outreach events in K-12 classes, local science centers, museums and public lectures such as the popular "Science Cafés".
