Cell-cell interaction in the Drosophila retina: the bride of sevenless gene is required in photoreceptor cell R8 for R7 cell development.
Genetic mosaic studies indicate that environmental cues play a critical role in photoreceptor cell (R-cell) development in the Drosophila compound eye. Recent analysis of the sevenless gene suggests that its product, a cell surface protein containing a putative intracellular domain homologous to tryosine kinases, is a receptor for a signal specifying an R7-specific pathway of cellular development. We report the identification of a second genetic locus, bride of sevenless (boss) required for the development of R7. Genetic mosaic analysis demonstrates that boss expression is required in the R8 cell for a neighboring cell to become R7. However, the development of R1-R6 and R8 is boss-independent. These data indicate a central role for R8 in directing ommatidial assembly and are consistent with boss encoding the ligand recognized by the sevenless receptor.
Reinke
R
R
Department of Biological Chemistry, UCLA School of Medicine.
Zipursky
S L
SL
D000818:Animals; D002450:Cell Communication; D002454:Cell Differentiation; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development; D005786:Gene Expression Regulation; D008854:Microscopy, Electron; D009030:Mosaicism; D010786:Photoreceptor Cells / Q000166:cytology*; D012160:Retina / Q000166:cytology*