Identification of a crystal cell-specific enhancer of the black cells prophenoloxidase gene in Drosophila.
In Drosophila, Black cells (Bc) encodes a Prophenoloxidase and is expressed late in the maturation of crystal cells, which are blood cells involved in wound healing and immune encapsulation. Enhancer analysis of Bc revealed a 1,025-bp upstream sequence that regulates gene expression in a crystal cell exclusive pattern. Expression of this fragment is altered by mutations in the GATA family serpent (srp) and RUNX family lozenge (lz) genes; Srp and Lz are required for crystal cell specification. Deletional analysis uncovered a 330-bp crystal cell-specific sequence, which contains two GATA and three Lz binding sites. Mutational analysis revealed that both GATA sites are necessary, but not sufficient for crystal cell expression. However, one of the Lz sites is essential for crystal cell expression. Thus, Srp and Lz do not just specify the crystal cell lineage, but also regulate the later differentiation of these cells. Additionally, we now have a sensitive tool for marking crystal cells in live animals.
Gajewski
Kathleen M
KM
Department of Biochemistry and Molecular Biology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Sorrentino
Richard P
RP
Lee
Joong H
JH
Zhang
Qian
Q
Russell
Mark
M
Schulz
Robert A
RA
D000818:Animals; D030801:Animals, Genetically Modified; D001665:Binding Sites; D004156:Catechol Oxidase / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D004268:DNA-Binding Proteins / Q000502:physiology; D004330:Drosophila / Q000166:cytology / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000502:physiology; D004625:Embryo, Nonmammalian; D004742:Enhancer Elements, Genetic / Q000502:physiology; D004792:Enzyme Precursors / Q000235:genetics* / Q000378:metabolism; D005260:Female; D050980:GATA Transcription Factors / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D006413:Hematopoietic System / Q000196:embryology / Q000378:metabolism; D006434:Hemocytes / Q000378:metabolism; D008297:Male; D009928:Organ Specificity; D014157:Transcription Factors / Q000502:physiology
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D004792:Enzyme Precursors; D050980:GATA Transcription Factors; D014157:Transcription Factors; C099964:lz protein, Drosophila; C103965:srp protein, Drosophila; C038451:pro-phenoloxidase; D004156:Catechol Oxidase