PT - JOURNAL ARTICLE AU - Couso, JP AU - Bate, M AU - Martinez-Arias, A TI - A wingless-dependent polar coordinate system in Drosophila imaginal discs AID - 10.1126/science.8424170 DP - 1993 Jan 22 TA - Science PG - 484--489 VI - 259 IP - 5094 4099 - http://science.sciencemag.org/content/259/5094/484.short 4100 - http://science.sciencemag.org/content/259/5094/484.full SO - Science1993 Jan 22; 259 AB - The patterning of the imaginal discs in Drosophila melanogaster is a progressive process that, like the patterning of the larval epidermis during embryogenesis, requires the activity of segment polarity genes. One segment polarity gene, wingless, encodes a homolog of the mouse proto-oncogene Wnt-1 and plays a prominent role in the patterning of the larval epidermis and the imaginal discs. However, whereas the function of wingless in the embryo is initially associated with a pattern of stripes along the anteroposterior axis that are part of a Cartesian coordinate system, it is shown here that during imaginal development wingless is associated with a pattern of sectors that provide references for a polar coordinate system homologous to that postulated in a well-known model for the regeneration of insect and vertebrate limbs.