PT  - JOURNAL ARTICLE
AU  - Martinez Arias, A.
AU  - Baker, N.E.
AU  - Ingham, P.W.
TI  - Role of segment polarity genes in the definition and maintenance of cell states in the Drosophila embryo
DP  - 1988 May 01
TA  - Development
PG  - 157--170
VI  - 103
IP  - 1
4099  - http://dev.biologists.org/content/103/1/157.short
4100  - http://dev.biologists.org/content/103/1/157.full
SO  - Development1988 May 01; 103
AB  - Segment polarity genes are expressed and required in restricted domains within each metameric unit of the Drosophila embryo. We have used the expression of two segment polarity genes engrailed (en) and wingless (wg) to monitor the effects of segment polarity mutants on the basic metameric pattern. Absence of patched (ptc) or naked (nkd) functions triggers a novel sequence of en and wg patterns. In addition, although wg and en are not expressed on the same cells absence of either one has effects on the expression of the other. These observations, together with an analysis of mutant phenotypes during development, lead us to suggest that positional information is encoded in cell states defined and maintained by the activity of segment polarity gene products.