• Eukaryotes
  • FtsZ, the first identified prokaryotic cytoskeletal element, forms a filamentous ring structure located in the middle of the cell called the Z-ring that constricts during cell division, similar to the actin-myosin contractile ring in eukaryotes. (wikipedia.org)
  • Domain
  • Thus, although it is useful to define phylogenetic patterns within each domain, it is not meaningful to construct phylogenetic classifications between domains: Prokaryotic kingdoms are not comparable to eukaryotic ones. (pnas.org)
  • The highest phylogenetic unit in the prokaryotic domain we think should be called an "urkingdom"-or perhaps "primary kingdom. (pnas.org)
  • A similar prejudice holds for the prokaryotic domain ( 2 ). (pnas.org)
  • The present communication is a discussion of recent findings that relate to the urkingdom structure of the prokaryotic domain and the question of its unique as opposed to multiple origin. (pnas.org)