bowl is expressed in the antennal disc during larval stages. In L1, it is expressed in many cells of the disc. In late L2, early L3, it is expressed in the ventral portion of the disc but excluded from the appendage region. The region extends posteriorly to the ventral limit between the antennal and eye portions of the disc and includes the prospective maxillary palp and ventral head regions. In late L3, bowl expression resolves into two rings in the antennal region and a stripe in the maxillary palp region of the disc. The pattern is coincident with that of EcollacZ^odd-rK111.

Transcript is observed in a segmentally repeated pattern in late third instar leg discs. Expression is observed in each presumptive leg segment including the tarsi. A broad stripe of expression is observed in each presumptive segment manifest as concentric rings. Expression is maintained in the everting pupal leg.

The anterior domain of bowl expression falls in two bands, one forms an anterior cap, the other forms a band between approximately 15 and 20% egg length. The two anterior domains are connected by solid ventral expression.

bowl transcripts accumulate in three domains in the cellular blastoderm embryo. The domains are a strong posterior cap from 0-11% egg length, a weak and nonuniform anterior domain from 84-100% egg length, and a broad transverse stripe (~6 cells wide) that lies just anterior to the presumptive cephalic furrow. At early gastrulation, expression is observed in seven pair-rule stripes that quickly evolve into a segment polarity pattern.

bowl transcripts are expressed in embryos from 2-4hrs on with a peak in 8-12hr embryos. bowl transcripts are detected in three distinct domains at the cellular blastoderm stage by in situ hybridization. They are found at the anterior and posterior poles and in a transverse stripe, approximately 6 cells wide, centered at 67% egg length at the dorsal midline and at 76% egg length at the ventral midline. During gastrulation and germ band extension, the posterior domain cells follow the amnioproctodeal invagination and are expressed in the posterior midgut and hindgut. The anterior domain cells invaginate with the anterior midgut. Some of the cells in the transverse stripe become part of the cephalic furrow. Later, cells in the invaginating stomodeum and cells that will give rise to the clypeolabrum express bowl. By germband retraction, expression in the hindgut and posterior midgut decreases while expression in the anterior midgut and foregut persists.

bowl protein is localized to proximal half of the true leg segments of leg discs; localization is distal to that of Dl and nub.

bowl is expressed in the antennal disc during larval stages. In L1, it is expressed in many cells of the disc. In late L2, early L3, it is expressed in the ventral portion of the disc but excluded from the appendage region. The region extends posteriorly to the ventral limit between the antennal and eye portions of the disc and includes the prospective maxillary palp and ventral head regions. In late L3, bowl expression resolves into two rings in the antennal region and a stripe in the maxillary palp region of the disc.

bowl protein accumumates in peripodial epithelial cells in the wing disc from the second larval instar. At early to mid third instar, bowl continues to be expressed in the peripodial epithelium, and at the lateral margins of the presumptive notum. bowl protein is absent from the disc epithelium proper in the wing disc. Late in larval development, bowl is downregulated in the medial region of the peripodial epithelium, and absent from its posterior margin. In everting discs in early pupae, bowl protein is detected at high levels in the ventro-anterior hinge, and at the lateral margins of the presumptive notum