title: An orderly retreat: Dedifferentiation is a regulated process.
abstract: Differentiation is a highly regulated process whereby cells become specialized to perform specific functions and lose the ability to perform others. In contrast, the question of whether dedifferentiation is a genetically determined process, or merely an unregulated loss of the differentiated state, has not been resolved. We show here that dedifferentiation in the social amoeba Dictyostelium discoideum relies on a sequence of events that is independent of the original developmental state and involves the coordinated expression of a specific set of genes. A defect in one of these genes, the histidine kinase dhkA, alters the kinetics of dedifferentiation and uncouples the progression of dedifferentiation events. These observations establish dedifferentiation as a genetically determined process and suggest the existence of a developmental checkpoint that ensures a return path to the undifferentiated state.
authors.affiliation: Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Mariko
authors.initials: M
authors.lastname: Katoh
authors.forename: Chad
authors.initials: C
authors.lastname: Shaw
authors.forename: Qikai
authors.initials: Q
authors.lastname: Xu
authors.forename: Nancy
authors.initials: N
authors.lastname: Van Driessche
authors.forename: Takahiro
authors.initials: T
authors.lastname: Morio
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Kuwayama
authors.forename: Shinji
authors.initials: S
authors.lastname: Obara
authors.forename: Hideko
authors.initials: H
authors.lastname: Urushihara
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Gad
authors.initials: G
authors.lastname: Shaulsky
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D004023:Dictyostelium / Q000502:physiology*; D020869:Gene Expression Profiling