DPANN archaea are a mysterious superphylum that is difficult to isolate and culture in the laboratory due to their specific culture conditions. DPANNs are characterized by their small size and limited metabolic capabilities1. Recently, our laboratory characterized the structural basis of the symbiotic relationship between a newly discovered DPANN Nanobdellota archaeon, YN1, and its host. Cryo-electron tomography (CryoET) revealed the presence of a large cone-shaped attachment organelle that facilitates the interaction between the nanoarchaeon and its host. This organelle, characterized by its large size and complexity, appears crucial for the stable association between YN1 and its host, suggesting a specialized mechanism for symbiosis in this system. However, to comprehensively understand the mechanism of symbiosis, it is imperative to examine the structure of these attachment organelles at both molecular and structural levels. Our current efforts are focused on purifying these attachment organelles to conduct detailed analyses through proteomic and biochemical assays, complemented by structural studies using CryoET and subtomogram averaging techniques. Our findings will shed light on the evolutionary dynamics and ecological significance of symbiotic relationships in archaea and provide valuable insights into how microbial interactions shape diverse ecosystems2.