The Drosophila Hox gene deformed sculpts head morphology via direct regulation of the apoptosis activator reaper.
Hox proteins control morphological diversity along the anterior-posterior body axis of animals, but the cellular processes they directly regulate are poorly understood. We show that during early Drosophila development, the Hox protein Deformed (Dfd) maintains the boundary between the maxillary and mandibular head lobes by activating localized apoptosis. Dfd accomplishes this by directly activating the cell death promoting gene reaper (rpr). One other Hox gene, Abdominal-B (Abd-B), also regulates segment boundaries through the regional activation of apoptosis. Thus, one mechanism used by Drosophila Hox genes to modulate segmental morphology is to regulate programmed cell death, which literally sculpts segments into distinct shapes. This and other emerging evidence suggests that Hox proteins may often regulate the maintenance of segment boundaries.
Section of Cell and Developmental Biology, University of California, San Diego, La Jolla 92093, USA.
Ingrid
I
Lohmann
Nadine
N
McGinnis
Morana
M
Bodmer
William
W
McGinnis
D000818:Animals; D017209:Apoptosis / Q000235:genetics*; D019521:Body Patterning / Q000235:genetics*; D002454:Cell Differentiation / Q000235:genetics; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics / Q000648:ultrastructure; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D005801:Genes, Homeobox / Q000235:genetics*; D006257:Head / Q000002:abnormalities* / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D007763:Lac Operon / Q000235:genetics; D008855:Microscopy, Electron, Scanning; D009154:Mutation / Q000235:genetics; D010455:Peptides / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000235:genetics; D015533:Transcriptional Activation / Q000235:genetics
C066676:Dfd protein, Drosophila; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D010455:Peptides; C086973:rpr protein, Drosophila