Evidence for redundancy but not trans factor-cis element coevolution in the regulation of Drosophila Yp genes.
In Drosophila melanogaster and the endemic Hawaiian species D. grimshawi three Yolk protein (Yp) genes are expressed in a similar sex- and tissue-specific pattern. In contrast, DNA sequence comparisons of promoter/enhancer regions show low levels of similarity. We tested the functional significance of these observations by transforming D. melanogaster with the genomic region that includes the divergently transcribed D. grimshawi DgYp1 and DgYp2 genes; we found that the introduced genes were expressed in female fat body and in ovaries but not in males. Moreover, we found D. grimshawi proteins in the hemolymph and accumulating in ovaries. Using reporter constructs we showed that the intergenic region from D. grimshawi was sufficient to drive accurate expression, but some low level of ectopic expression was seen in males. Transforming D. melanogaster with constructs bearing deletions within the D. grimshawi intergenic region revealed only subtle effects in the overall level of expression, suggesting a high level of redundancy. Testing mutants in the sex-specific regulator doublesex revealed that it is capable of repressing the DgYp genes in males. Together, these data show that D. melanogaster trans-acting factors can regulate the in vivo pattern of DgYp expression and support the notion of a redundant and complex system of cis-acting elements.
Piano
F
F
Department of Biology, New York University, New York, New York 10003, USA.
Parisi
M J
MJ
Karess
R
R
Kambysellis
M P
MP
D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D004247:DNA / Q000235:genetics; D004268:DNA-Binding Proteins / Q000502:physiology; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics; D004527:Egg Proteins / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D019143:Evolution, Molecular; D005260:Female; D005786:Gene Expression Regulation; D019476:Insect Proteins / Q000502:physiology; D008297:Male; D010053:Ovary / Q000378:metabolism; D012313:RNA / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012737:Sex Factors; D014018:Tissue Distribution
D004268:DNA-Binding Proteins; C070369:DSX protein, Drosophila; D029721:Drosophila Proteins; D004527:Egg Proteins; D019476:Insect Proteins; D011993:Recombinant Fusion Proteins; D012313:RNA; D004247:DNA