title: Botryllus schlosseri, an emerging model for the study of aging, stem cells, and mechanisms of regeneration.
abstract: The decline of tissue regenerative potential with the loss of stem cell function is a hallmark of mammalian aging. We studyBotryllus schlosseri,a colonial chordate which exhibits robust stem cell-mediated regeneration capacities throughout life. Larvae, derived by sexual reproduction and chordate development, metamorphose to clonal founders that undergo weekly formation of new individuals by budding from stem cells. Individuals are transient structures which die through massive apoptosis, and successive buds mature to replicate an entire new body. As a result, their stem cells, which are the only self-renewing cells in a tissue, are the only cells which remain through the entire life of the genotype and retain the effects of time. During aging, a significant decrease in the colonies' regenerative potential is observed and both sexual and asexual reproductions will eventually halt. When a parent colony is experimentally separated into a number of clonal replicates, they frequently undergo senescence simultaneously, suggesting a heritable factor that determines lifespan in these colonies. The availability of the recently publishedB. schlosserigenome coupled with its unique life cycle features promotes the use of this model organism for the study of the evolution of aging, stem cells, and mechanisms of regeneration.
authors.affiliation: Department of Pathology, Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, and Hopkins Marine Station , Stanford , CA , USA.
authors.forename: Ayelet
authors.initials: A
authors.lastname: Voskoboynik
authors.affiliation: Department of Pathology, Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, and Hopkins Marine Station , Stanford , CA , USA ; Ludwig Center for Cancer Stem Cell Research and Medicine, Stanford University School of Medicine , Stanford , CA , USA.
authors.forename: Irving L
authors.initials: IL
authors.lastname: Weissman
keywords: Botryllus schlosseri; aging; asexual development; regeneration; stem cells; urochordate