Totipotent migratory stem cells in a hydroid.
Hydroids, members of the most ancient eumetazoan phylum, the Cnidaria, harbor multipotent, migratory stem cells lodged in interstitial spaces of epithelial cells and are therefore referred to as interstitial cells or i-cells. According to traditional understanding, based on studies in Hydra, these i-cells give rise to several cell types such as stinging cells, nerve cells, and germ cells, but not to ectodermal and endodermal epithelial cells; these are considered to constitute separate cell lineages. We show here that, in Hydractinia, the developmental potential of these migratory stem cells is wider than previously anticipated. We eliminated the i-cells from subcloned wild-type animals and subsequently introduced i-cells from mutant clones and vice versa. The mutant donors and the wild-type recipients differed in their sex, growth pattern, and morphology. With time, the recipient underwent a complete conversion into the phenotype and genotype of the donor. Thus, under these experimental conditions the interstitial stem cells of Hydractinia exhibit totipotency.
Institute of Zoology, University of Heidelberg, D-69120 Heidelberg, Germany. w.muller@zoo.uni-heidelberg.de
Werner A
WA
Müller
Regina
R
Teo
Uri
U
Frank
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001973:Bromodeoxyuridine; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology*; D002678:Chimera / Q000502:physiology; D003063:Cnidaria / Q000502:physiology*; D016685:Mitomycin / Q000494:pharmacology; D013194:Staining and Labeling; D039901:Totipotent Stem Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*
D000903:Antibiotics, Antineoplastic; D016685:Mitomycin; D001973:Bromodeoxyuridine