Feedback inhibition of JAK/STAT signaling by Apontic required to limit a migratory and invasive cell population

MICHELLE STARZ-GAIANO* (CONTRIBUTED EQUALLY); MARIANA MELANI* (CONTRIBUTED EQUALLY); XIAOBO WANG; HANS H. MEINHARDT; DENISE J. MONTELL

DEVELOPMENTAL CELL

ELSEVIER

Año: 2008 vol. 14 p. 726 - 738

1534-5807

In both normal development and in a variety of pathological conditions, epithelial cells can acquire migratory and invasive properties. Border cells in the Drosophila ovary provide a genetically tractable model for elucidating the mechanisms controlling such behaviors. Here we report the identification of a mutant, apontic (apt), in which the migratory population expanded and separation from the epithelium was impeded. This phenotype resembled gain-of-function of JAK/STAT activity. Gain-of-function of APT also mimicked loss of function of STAT and its key downstream target, SLBO. APT expression was induced by STAT, which bound directly to sites in the apt gene. The data suggest that a regulatory circuit between STAT, APT, and SLBO functions to convert an initially graded signal into an all-or-nothing activation of JAK/STAT and thus to proper cell specification and migration. These findings are supported by a mathematical model, which accurately simulates wild-type and mutant phenotypes.