Deterin, a New Inhibitor of Apoptosis from Drosophila melanogaster

doi:10.1074/jbc.M000369200

Deterin, a New Inhibitor of Apoptosis from *Drosophila melanogaster**

Abstract

Deterin, a new apoptosis inhibitor fromDrosophila melanogaster, possesses an unusual structure of only a single baculovirus inhibitor of apoptosis (IAP)-type repeat and no RING finger motif. The biochemical actions of deterin are demonstrated in SF9 and S2 cell transfection assays, in which the expressed protein acts in the cytoplasm to inhibit or deter cells from apoptosis otherwise induced by the caspase-dependent apoptosis activator reaper or by cytotoxicants. A loss of function phenotype for deterin of cell death was indicated by transfections with either a dominant negative deterin mutant or with inhibitory RNA (RNAi) for deterin. The dominant negative C-terminal fragment that antagonized antiapoptotic activity of deterin did not affect antiapoptotic activity of DIAP1 or p35. Both the baculovirus IAP-type repeat (BIR) domain and the α-helical C-terminal domain are necessary in both SF9 and S2 cells for deterin to manifest its activity to prevent cell death. The approximately 650-base deterin transcript is present in embryos, third instar larvae, and late stage nurse cells of adult females. The deterin transcript is distributed throughout early stage embryos, whereas in later stage embryos it becomes progressively restricted to the central nervous system and gonads. Whereas the nematode survivin-type IAP has thus far been implicated only as a mitotic regulator,Drosophila deterin constitutes the first invertebrate member of the survivin-type IAP group to exhibit apoptosis-inhibitory activity.

Footnotes

↵* This work was supported in part by National Institutes of Health Grants DK39197 and GM 60121 (to G. J.) and by National Institutes of Health Grants GM 33995 and CA 81537 (to D. J.).The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
↵§ These authors contributed with equal responsibility and effort to this work.
↵¶ To whom correspondence should be addressed. Tel.: 606-257-3795; Fax: 606-257-7505; E-mail: gjones@pop.uky.edu.
↵** To whom correspondence should be addressed. Tel.: 606-257-5412; Fax: 606-323-1059; E-mail: djones@pop.uky.edu.
↵§§ Postdoctoral Associate.
↵¶¶ An Investigator of the Howard Hughes Medical Institute, Massachusetts Institute of Technology (Cambridge, MA).
Published, JBC Papers in Press, April 11, 2000, DOI 10.1074/jbc.M000369200
Abbreviations:

IAP

inhibitors of apoptosis

β-gal

β-galactosidase

GFP

green fluorescent protein

PBT

phosphate-buffered saline, pH 7.4, 0.1% Tween

PCR

polymerase chain reaction

RNAi

RNA-mediated interference

RT

reverse transcription

BIR

baculovirus IAP-type repeat
- Received January 14, 2000.
- Revision received April 11, 2000.
The American Society for Biochemistry and Molecular Biology, Inc.