Pattern formation is important in biological processes both at the microscopic level and at the macroscopic level. An embryo starts as a single cell and with development forms beautiful patterns that provide the first imprints of the animal body plan. Using Drosophila as model organism we study pattern formation at very early embryogenesis. Right after fertilization of the egg, nuclear division takes place without cell division, and these nuclei migrate to the periphery of the single syncytial cell. To form separate nuclear compartments at the periphery, the membrane forms furrows around each nucleus. There are two juxtaposed networks that engage each other to drive this furrow formation. One network is an expanding Arp2/3 actin network and another is a contractile actomyosin network. We hypothesize that the physical interaction between these two materials leads to a specific pattern, a contractile sheet embedded with circular clearances that each proceed to form a nuclear compartment. In this study, we develop a mathematical model in which the pulling of actin by myosin is simulated by spring-bead dynamics utilizing rule-based modeling, and the growing actin cap is mimicked using diffusion dynamics. Our in silico study is based on in vivo imaging of how elements of the networks assemble in space and time in wild type embryos and in mutants where either network is depleted. By re-constitution in silico, we will assess how the physical interaction of neighboring cytoskeletal networks can pattern the cell cortex.