Elements controlling follicular expression of the s36 chorion gene during Drosophila oogenesis.
An 84-bp proximal regulatory protein (PRR) of the Drosophila melanogaster s36 chorion gene is sufficient for directing proper temporal and spatial expression of a reporter gene in three domains of the follicle: anterior, posterior, and main body. Here we show that the fidelity of PRR-directed s36 expression is dependent on the proper dorsal-ventral differentiation of the follicular epithelium, which requires the Drosophila epidermal growth factor receptor homolog. Transgenic analysis of site-directed mutants of the PRR suggests that s36 expression is regulated by the concerted action of multiple positive activators. Several cis-acting transcriptional elements have been identified: some appear to function in a quantitative manner, while others either are essential or appear to regulate expression in particular spatial domains. The approximate locations of these regulatory elements have been defined; some map within sequences that are strongly conserved in widely divergent dipteran species. In fact, the PRR analog of the medfly Ceratitis capitata Ccs36 gene directs expression in a manner similar to the D. melanogaster s36 PRR. We propose a model for transcriptional regulation of s36 based on the prechoriogenic polarization of the follicular epithelium that surrounds the developing egg chamber.
Tolias
P P
PP
Public Health Research Institute, New York, New York 10016.
Konsolaki
M
M
Halfon
M S
MS
Stroumbakis
N D
ND
Kafatos
F C
FC
D000818:Animals; D001483:Base Sequence; D002823:Chorion; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics*; D004527:Egg Proteins / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D017344:Genes, Insect; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009866:Oogenesis; D010053:Ovary / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid
D004527:Egg Proteins