Abstract:
During organogenesis in all multi-cellular organisms, axial patterning is required to transform a single
layer organ primordium into a three-dimensional organ. The Drosophila eye model serves as an excellent
model to study axial patterning. Dorso-ventral (DV) axis determination is the first lineage restriction
event during axial patterning of the Drosophila eye. The early Drosophila eye primordium has a
default ventral fate, and the dorsal eye fate is established by onset of dorsal selector gene pannier (pnr)
expression in a group of cells on the dorsal eye margin. The boundary between dorsal and ventral com-
partments called the equator is the site for Notch (N) activation, which triggers cell proliferation and dif-
ferentiation. This review will focus on (1) chronology of events during DV axis determination; (2)
how early division of eye into dorsal and ventral compartments contributes towards the growth and pat-
terning of the fly retina, and (3) functions of DV patterning genes.