Cytochrome c-d regulates developmental apoptosis in the Drosophila retina

• Published in: EMBO reports Vol. 7; no. 9; pp. 933 - 939
• Main Authors: Mendes, César S, Arama, Eli, Brown, Samara, Scherr, Heather, Srivastava, Mayank, Bergmann, Andreas, Steller, Hermann, Mollereau, Bertrand
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.09.2006; Blackwell Publishing Ltd
• Subjects: Alleles; Animals; Apoptosis; Biochemistry; Caspases - genetics; Caspases - physiology; Cell Differentiation; Cell Respiration; Cytochrome; Cytochromes c - genetics; Cytochromes c - physiology; Drosophila; Drosophila melanogaster - embryology; Drosophila melanogaster - genetics; Drosophila Proteins - genetics; Drosophila Proteins - physiology; Embryos; Eye; Genes; Invertebrates; Mammals; Molecular biology; Mosquitoes; Mutants; Mutation; Physiology; Pupa - metabolism; Respiration; Retina; Retina - cytology; Retina - embryology; Retina - metabolism; Scientific Report
• ISSN: 1469-221X; 1469-3178; 1469-221X
• DOI: 10.1038/sj.embor.7400773

The role of cytochrome c (Cyt c) in caspase activation has largely been established from mammalian cell‐culture studies, but much remains to be learned about its physiological relevance in situ. The role of Cyt c in invertebrates has been subject to considerable controversy. The Drosophila genome contains distinct cyt c genes: cyt c‐p and cyt c‐d. Loss of cyt c‐p function causes embryonic lethality owing to a requirement of the gene for mitochondrial respiration. By contrast, cyt c‐d mutants are viable but male sterile. Here, we show that cyt c‐d regulates developmental apoptosis in the pupal eye. cyt c‐d mutant retinas show a profound delay in the apoptosis of superfluous interommatidial cells and perimeter ommatidial cells. Furthermore, there is no apoptosis in mutant retinal tissues for the Drosophila homologues of apoptotic protease‐activating factor 1 (Ark) and caspase 9 (Dronc). In addition, we found that cyt c‐d—as with ark and dronc—regulates scutellar bristle number, which is known to depend on caspase activity. Collectively, our results indicate a role of Cyt c in caspase regulation of Drosophila somatic cells.