GATAe-dependent and -independent expressions of genes in the differentiated endodermal midgut of Drosophila.
Two sequentially-expressed GATA factor genes, serpent (srp) and GATAe, are essential for development of the Drosophila endoderm. The earliest endodermal GATA gene, srp, has been thought to specify the endodermal fate, activating the second GATA gene GATAe, and the latter continues to be expressed in the endodermal midgut throughout life. Previously, we proposed that GATAe establishes and maintains the state of terminal differentiation of the midgut, since some functional genes in the midgut require GATAe activity for their expression. To obtain further evidence of the role of GATAe, we searched for additional genes that are expressed specifically in the midgut in late stages, and examined responses of a total of selected 15 genes to the depletion and overexpression of GATAe. Ten of the 15 genes failed to be expressed in the embryo deficient for GATAe activity, but, the other five genes did not require GATAe. Instead, srp is required for activating the five genes. These observations indicate that GATAe activates a major subset of genes in the midgut, and some other pathway(s) downstream of srp activates other genes.
Okumura
Takashi
T
Department of Biology and Chemistry, Yamaguchi University, Yoshida 1677-1, Yamaguchi 753-8512, Japan.
Tajiri
Reiko
R
Kojima
Tetsuya
T
Saigo
Kaoru
K
Murakami
Ryutaro
R
D000818:Animals; D004064:Digestive System / Q000196:embryology / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D004707:Endoderm / Q000378:metabolism; D050980:GATA Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D005819:Genetic Markers; D008957:Models, Genetic
D029721:Drosophila Proteins; D050980:GATA Transcription Factors; C499641:GATAe protein, Drosophila; D005819:Genetic Markers; C103965:srp protein, Drosophila