Aggregative multicellularity (also termed sorocarpic multicellularity) has evolved independently many times among both eukaryotes and prokaryotes. When starved or exposed to environmental strees, the cells can cooperate to form fruiting body (sorocarp) consisting of resilient cysts or spores. Among eukaryotes, this type of quasi-multicellular behavior is well studied in dictyostelids (e.g. Dictyostelium discoideum). Acrasis species are common soil microbes frequently encountered in the surveys for the “sorocarpic amoebae”, and they were long considered the primitive sister taxon to dictyostelids. However, Acrasids belong to one of the earliest major branches of eukaryotes, the excavates, for which there is very limited molecular data and a high potential for the discovery of genetic novelty. We have completed sequencing and annotation of the A. kona nuclear genome. We are particularly interested in gene evolution and regulation associated with the development of aggregation. This will be done by comparing genomic data from aggregating versus non-aggregating amoebas. RNAseq analysis will be conducted from the main stages of the A. kona life cycle.