Interested in promotions? | Click here >>

Product listing: BID Antibody (Human Specific), UniProt ID P55957 #2002 to Cleaved Drosophila Dcp-1 (Asp216) Antibody, UniProt ID O02002 #9578

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Bid is a pro-apoptotic “BH3 domain-only” member of the Bcl-2 family originally discovered to interact with both the anti-apoptotic family member Bcl-2 and the pro-apoptotic protein Bax (1). Bid is normally localized in the cytosolic fraction of cells as an inactive precursor and is cleaved at Asp60 by caspase-8 during Fas signaling, leading to translocation of the carboxyl terminal p15 fragment (tBid) to the mitochondrial outer membrane (2-4). Translocation of Bid is associated with release of cytochrome c from the mitochondria, leading to complex formation with Apaf-1 and caspase-9 and resulting in caspase-9 activation (5-7). Thus, Bid relays an apoptotic signal from the cell surface to the mitochondria triggering caspase activation (8,9).

$260
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Western Blotting

Background: Bid is a pro-apoptotic “BH3 domain-only” member of the Bcl-2 family originally discovered to interact with both the anti-apoptotic family member Bcl-2 and the pro-apoptotic protein Bax (1). Bid is normally localized in the cytosolic fraction of cells as an inactive precursor and is cleaved at Asp60 by caspase-8 during Fas signaling, leading to translocation of the carboxyl terminal p15 fragment (tBid) to the mitochondrial outer membrane (2-4). Translocation of Bid is associated with release of cytochrome c from the mitochondria, leading to complex formation with Apaf-1 and caspase-9 and resulting in caspase-9 activation (5-7). Thus, Bid relays an apoptotic signal from the cell surface to the mitochondria triggering caspase activation (8,9).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Bik/Nbk (Bcl-2-interacting killer/natural born killer) is a potent pro-apoptotic protein belonging to a group of Bcl-2 family members that includes Bad, Bid, Bim, Hrk, and Noxa, containing a BH3 domain but lacking other conserved domains, BH1 or BH2 (1,2). Functionally, Bik is able to bind to and antagonize anti-apoptotic Bcl-2 family members including Bcl-2, Bcl-xL, and viral homologs E1B-19K and EBV-BHFR1. The BH3 domain of Bik is essential for its apoptotic activity and interaction with survival proteins (3). Phosphorylation of Bik is correlated with an increase in its pro-apoptotic activity (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Bim/Bod is a pro-apoptotic protein belonging to the BH3-only group of Bcl-2 family members including Bad, Bid, Bik, Hrk, and Noxa that contain a BH3 domain but lack other conserved BH1 or BH2 domains (1,2). Bim induces apoptosis by binding to and antagonizing anti-apoptotic members of the Bcl-2 family. Interactions have been observed with Bcl-2, Bcl-xL, Mcl-1, Bcl-w, Bfl-1, and BHRF-1 (1,2). Bim functions in regulating apoptosis associated with thymocyte negative selection and following growth factor withdrawal, during which Bim expression is elevated (3-6). Three major isoforms of Bim are generated by alternative splicing: BimEL, BimL, and BimS (1). The shortest form, BimS, is the most cytotoxic and is generally only transiently expressed during apoptosis. The BimEL and BimL isoforms may be sequestered to the dynein motor complex through an interaction with the dynein light chain and released from this complex during apoptosis (7). Apoptotic activity of these longer isoforms may be regulated by phosphorylation (8,9). Environmental stress triggers Bim phosphorylation by JNK and results in its dissociation from the dynein complex and increased apoptotic activity.

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Bit1 is a mitochondrial protein discovered as a regulator of anoikis, a process of apoptosis triggered by the loss of cell adhesion to the extracellular matrix (1,2). Like several other mitochondrial apoptotic regulators (Cytochrome c, Smac, HtrA2, AIF, EndoG), Bit1 is released into the cytoplasm during apoptosis (1,3). Cytoplasmic Bit1 associates with the Groucho family of transcriptional regulator AES (1,4). Interaction between Bit1 and AES promotes apoptosis, and this complex is suppressed by integrin mediated cell attachment.

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: The inhibitor of apoptosis protein (IAP) family consists of an evolutionarily conserved group of apoptosis inhibitors containing a conserved 70 amino acid BIR (baculovirus inhibitor repeat) domain (1,2). Human members of this family include c-IAP1, c-IAP2, XIAP, survivin, livin, and NAIP. Overexpression of IAP family members, particularly survivin and livin, in cancer cell lines and primary tumors suggests an important role for these proteins in cancer progression (3-5). In general, the IAP proteins function through direct interactions to inhibit the activity of several caspases, including caspase-3, caspase-7, and caspase-9 (5,6). In addition, binding of IAP family members to the mitochondrial protein Smac blocks their interaction with caspase-9, thereby allowing the processing and activation of the caspase (2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Chromatin IP, Immunoprecipitation, Western Blotting

Background: Members of the Myc/Max/Mad network function as transcriptional regulators with roles in various aspects of cell behavior including proliferation, differentiation and apoptosis (1). These proteins share a common basic-helix-loop-helix leucine zipper (bHLH-ZIP) motif required for dimerization and DNA-binding. Max was originally discovered based on its ability to associate with c-Myc and found to be required for the ability of Myc to bind DNA and activate transcription (2). Subsequently, Max has been viewed as a central component of the transcriptional network, forming homodimers as well as heterodimers with other members of the Myc and Mad families (1). The association between Max and either Myc or Mad can have opposing effects on transcriptional regulation and cell behavior (1). The Mad family consists of four related proteins; Mad1, Mad2 (Mxi1), Mad3 and Mad4, and the more distantly related members of the bHLH-ZIP family, Mnt and Mga. Like Myc, the Mad proteins are tightly regulated with short half-lives. In general, Mad family members interfere with Myc-mediated processes such as proliferation, transformation and prevention of apoptosis by inhibiting transcription (3,4).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Caspase-1, or interleukin-1ß converting enzyme (ICE/ICEα), is a class I cysteine protease, which also includes caspases -4, -5, -11, and -12. Caspase-1 cleaves inflammatory cytokines such as pro-IL-1ß and interferon-γ inducing factor (IL-18) into their mature forms (1,2). Like other caspases, caspase-1 is proteolytically activated from a proenzyme to produce a tetramer of its two active subunits, p20 and p10. Caspase-1 has a large amino-terminal pro-domain that contains a caspase recruitment domain (CARD). Overexpression of caspase-1 can induce apoptosis (3). Mice deficient in caspase-1, however, have no overt defects in apoptosis but do have defects in the maturation of pro-IL-1β and are resistant to endotoxic shock (4,5). At least six caspase-1 isoforms have been identified, including caspase-1 α, β, γ, δ, ε and ζ (6). Most caspase-1 isoforms (α, β, γ and δ) produce products between 30-48 kDa and induce apoptosis upon over-expression. Caspase-1 ε typically contains only the p10 subunit, does not induce apoptosis and may act as a dominant negative. The widely expressed ζ isoform of caspase-1 induces apoptosis and lacks 39 amino-terminal residues found in the α isoform (6). Activation of caspase-1 occurs through an oligomerization molecular platform designated the "inflammasome" that includes caspase-5, Pycard/Asc, and NALP1 (7).

$111
20 µl
$261
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Western Blotting

Background: Caspase-12 is located in the endoplasmic reticulum (ER). It is responsible for ER-stress-induced apoptosis, such as high calcium concentration, low oxygen and low glucose levels (1,2). One of the mechanisms for caspase-12 activation is related to calpain mediated cleavage at T132 and K158, both of which are located at the amino-terminal region of the caspase-12 (2,3). Caspase-12 also has a putative caspase cleavage site located at the carboxy-terminal region of the protein (3). In cortical neurons, caspase-12 is involved at least partially in the amyloid-beta neurotoxicity process (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Caspases are a family of cysteine proteases that play an essential role in carrying out apoptosis. Caspase-14, also named MICE, is a unique member of the caspase family with restricted expression; it is found in embryonic tissues and adult skin (1,2). Caspase-14 is weakly processed into p18 and p11 subunits by caspase-8 (2). Caspase-14 may not play a role in apoptosis (2), but instead may regulate keratinocyte differentiation (3). Expression of caspase-14 may protect from psoriasis (4,5) and irradiation damage (6). Caspase-14 may also be responsible for proteolytic processing of filaggrin during terminal differentiation of keratinocytes (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Caspase-3 (CPP-32, Apoptain, Yama, SCA-1) is a critical executioner of apoptosis, as it is either partially or totally responsible for the proteolytic cleavage of many key proteins, such as the nuclear enzyme poly (ADP-ribose) polymerase (PARP) (1). Activation of caspase-3 requires proteolytic processing of its inactive zymogen into activated p17 and p12 fragments. Cleavage of caspase-3 requires the aspartic acid residue at the P1 position (2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Caspase-4 (TX/ICH-2/ICErelII) is a member of the caspase family of proteases that play a key role in the execution of apoptosis and activation of inflammatory cytokines (1-3). Expression of caspase-4 has been observed in most tissues except brain, with highest levels in placenta, lung, spleen, and peripheral blood lymphocytes (PBL). Caspase-4 was originally found to contribute to Fas-mediated apoptosis (4). Several caspases (including caspase-4, caspase-5, and mouse caspase-11 and -12) are most closely related to caspase-1 and are capable of inducing apoptosis when over-expressed but are better characterized in the proteolytic activation of inflammatory cytokines (5). Caspase-4 associates with TRAF6 and is involved in the LPS inducible production of inflammatory cytokines IL-8 and MIP1 in THP-1 cells (6). While caspase-4 and mouse caspase-12 localize to the endoplasmic reticulum (ER) and may be activated by drugs that induce ER-stress (7), at least one study suggests that caspase-4 and caspase-12 are not essential for the ER-stress induced apoptosis (8).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Caspase-6 (Mch2) is one of the major executioner caspases functioning in cellular apoptotic processes (1,2). Upon apoptotic stimulation, initiator caspases such as caspase-9 are cleaved and activated (3). The activated upstream caspases further process downstream executioner caspases, such as caspase-3 and caspase-6, by cleaving them into large and small subunits, thereby initiating a caspase cascade leading to apoptosis (4,5). One of the major targets for caspase-6 is the membrane associated protein lamin A (6). The cleavage of this protein causes cell membrane malfunction, membrane blebbing and eventual cell death.

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: Caspase-7 (CMH-1, Mch3, ICE-LAP3) has been identified as a major contributor to the execution of apoptosis (1-4). Caspase-7, like caspase-3, is an effector caspase that is responsible for cleaving downstream substrates such as (ADP-ribose) polymerase and PARP (1,3). During apoptosis, caspase-7 is activated through proteolytic processing by upstream caspases at Asp23, Asp198, and Asp206 to produce the mature subunits (1,3). Similar to caspase-2 and -3, caspase-7 preferentially cleaves substrates following the recognition sequence DEVD (5).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Western Blotting

Background: Apoptosis induced through the CD95 receptor (Fas/APO-1) and tumor necrosis factor receptor 1 (TNFR1) activates caspase-8 and leads to the release of the caspase-8 active fragments, p18 and p10 (1-3). Activated caspase-8 cleaves and activates downstream effector caspases such as caspase-1, -3, -6, and -7. Caspase-3 ultimately elicits the morphological hallmarks of apoptosis, including DNA fragmentation and cell shrinkage.

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Western Blotting

Background: Caspase-9 (ICE-LAP6, Mch6) is an important member of the cysteine aspartic acid protease (caspase) family (1,2). Upon apoptotic stimulation, cytochrome c released from mitochondria associates with the 47 kDa procaspase-9/Apaf-1. Apaf-1 mediated activation of caspase-9 involves intrinsic proteolytic processing resulting in cleavage at Asp315 and producing a p35 subunit. Another cleavage occurs at Asp330 producing a p37 subunit that can serve to amplify the apoptotic response (3-6). Cleaved caspase-9 further processes other caspase members, including caspase-3 and caspase-7, to initiate a caspase cascade, which leads to apoptosis (7-10).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Western Blotting

Background: Caspase-9 (ICE-LAP6, Mch6) is an important member of the cysteine aspartic acid protease (caspase) family (1,2). Upon apoptotic stimulation, cytochrome c released from mitochondria associates with the 47 kDa procaspase-9/Apaf-1. Apaf-1 mediated activation of caspase-9 involves intrinsic proteolytic processing resulting in cleavage at Asp315 and producing a p35 subunit. Another cleavage occurs at Asp330 producing a p37 subunit that can serve to amplify the apoptotic response (3-6). Cleaved caspase-9 further processes other caspase members, including caspase-3 and caspase-7, to initiate a caspase cascade, which leads to apoptosis (7-10).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Cathepsin B (CSTB), part of the papain family of proteases, is a widely expressed lysosomal cysteine endopeptidase (1,2). Cathepsin B is produced from a larger precursor form, pro-cathepsin B, which runs at approximately 44 kDa on SDS-PAGE, and is proteolytically processed and glycosylated to form a mature two-chain protein containing a heavy chain (running at 27 and 24 kDa) and a light chain (5 kDa). High levels of cathepsin B are found in macrophages and osteoclasts, as well as various types of cancer cells, including lung, colon, prostate, breast, and stomach. In addition, expression of cathepsin B has been associated with multiple sclerosis (3), rheumatoid arthritis (4), and pancreatitis (5). While generally localized to lysosomes, in cancer alterations can lead to its secretion (6). Its role in tumor progression is thought to involve promotion of basement membrane degradation, invasion and metastasis (7,8). Expression can correlate with poor prognosis for a variety of forms of cancer (9-13).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: Cathepsin B (CSTB), part of the papain family of proteases, is a widely expressed lysosomal cysteine endopeptidase (1,2). Cathepsin B is produced from a larger precursor form, pro-cathepsin B, which runs at approximately 44 kDa on SDS-PAGE, and is proteolytically processed and glycosylated to form a mature two-chain protein containing a heavy chain (running at 27 and 24 kDa) and a light chain (5 kDa). High levels of cathepsin B are found in macrophages and osteoclasts, as well as various types of cancer cells, including lung, colon, prostate, breast, and stomach. In addition, expression of cathepsin B has been associated with multiple sclerosis (3), rheumatoid arthritis (4), and pancreatitis (5). While generally localized to lysosomes, in cancer alterations can lead to its secretion (6). Its role in tumor progression is thought to involve promotion of basement membrane degradation, invasion and metastasis (7,8). Expression can correlate with poor prognosis for a variety of forms of cancer (9-13).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Cell Death Involved p53-Target (CDIP) is a pro-apoptotic protein induced by genotoxic stress in a p53-dependent manner (1). Indeed, CDIP is a direct target of p53. Inhibition of CDIP impairs p53-mediated apoptosis. Induction of apoptosis by CDIP requires caspase-8 suggesting involvement in the extrinsic apoptotic pathway. CDIP also promotes increased expression of TNF-α capable of triggering apoptosis. Furthermore, expression of CDIP correlates with increased sensitivity of TNF-α-induced apoptosis (2). These studies suggest that CDIP may serve as a marker for apoptotic sensitivity.

$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometry and immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Cleaved Caspase-3 (Asp175) Antibody #9661.
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry)

Background: Caspase-3 (CPP-32, Apoptain, Yama, SCA-1) is a critical executioner of apoptosis, as it is either partially or totally responsible for the proteolytic cleavage of many key proteins, such as the nuclear enzyme poly (ADP-ribose) polymerase (PARP) (1). Activation of caspase-3 requires proteolytic processing of its inactive zymogen into activated p17 and p12 fragments. Cleavage of caspase-3 requires the aspartic acid residue at the P1 position (2).

$117
20 µl
$303
100 µl
$717
300 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Caspase-3 (CPP-32, Apoptain, Yama, SCA-1) is a critical executioner of apoptosis, as it is either partially or totally responsible for the proteolytic cleavage of many key proteins, such as the nuclear enzyme poly (ADP-ribose) polymerase (PARP) (1). Activation of caspase-3 requires proteolytic processing of its inactive zymogen into activated p17 and p12 fragments. Cleavage of caspase-3 requires the aspartic acid residue at the P1 position (2).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Caspase-6 (Mch2) is one of the major executioner caspases functioning in cellular apoptotic processes (1,2). Upon apoptotic stimulation, initiator caspases such as caspase-9 are cleaved and activated (3). The activated upstream caspases further process downstream executioner caspases, such as caspase-3 and caspase-6, by cleaving them into large and small subunits, thereby initiating a caspase cascade leading to apoptosis (4,5). One of the major targets for caspase-6 is the membrane associated protein lamin A (6). The cleavage of this protein causes cell membrane malfunction, membrane blebbing and eventual cell death.

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Caspase-7 (CMH-1, Mch3, ICE-LAP3) has been identified as a major contributor to the execution of apoptosis (1-4). Caspase-7, like caspase-3, is an effector caspase that is responsible for cleaving downstream substrates such as (ADP-ribose) polymerase and PARP (1,3). During apoptosis, caspase-7 is activated through proteolytic processing by upstream caspases at Asp23, Asp198, and Asp206 to produce the mature subunits (1,3). Similar to caspase-2 and -3, caspase-7 preferentially cleaves substrates following the recognition sequence DEVD (5).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Western Blotting

Background: Apoptosis induced through the CD95 receptor (Fas/APO-1) and tumor necrosis factor receptor 1 (TNFR1) activates caspase-8 and leads to the release of the caspase-8 active fragments, p18 and p10 (1-3). Activated caspase-8 cleaves and activates downstream effector caspases such as caspase-1, -3, -6, and -7. Caspase-3 ultimately elicits the morphological hallmarks of apoptosis, including DNA fragmentation and cell shrinkage.

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Caspase-9 (ICE-LAP6, Mch6) is an important member of the cysteine aspartic acid protease (caspase) family (1,2). Upon apoptotic stimulation, cytochrome c released from mitochondria associates with the 47 kDa procaspase-9/Apaf-1. Apaf-1 mediated activation of caspase-9 involves intrinsic proteolytic processing resulting in cleavage at Asp315 and producing a p35 subunit. Another cleavage occurs at Asp330 producing a p37 subunit that can serve to amplify the apoptotic response (3-6). Cleaved caspase-9 further processes other caspase members, including caspase-3 and caspase-7, to initiate a caspase cascade, which leads to apoptosis (7-10).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Caspase-9 (ICE-LAP6, Mch6) is an important member of the cysteine aspartic acid protease (caspase) family (1,2). Upon apoptotic stimulation, cytochrome c released from mitochondria associates with the 47 kDa procaspase-9/Apaf-1. Apaf-1 mediated activation of caspase-9 involves intrinsic proteolytic processing resulting in cleavage at Asp315 and producing a p35 subunit. Another cleavage occurs at Asp330 producing a p37 subunit that can serve to amplify the apoptotic response (3-6). Cleaved caspase-9 further processes other caspase members, including caspase-3 and caspase-7, to initiate a caspase cascade, which leads to apoptosis (7-10).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Immunofluorescence (Immunocytochemistry), Western Blotting

Background: Caspase-9 (ICE-LAP6, Mch6) is an important member of the cysteine aspartic acid protease (caspase) family (1,2). Upon apoptotic stimulation, cytochrome c released from mitochondria associates with the 47 kDa procaspase-9/Apaf-1. Apaf-1 mediated activation of caspase-9 involves intrinsic proteolytic processing resulting in cleavage at Asp315 and producing a p35 subunit. Another cleavage occurs at Asp330 producing a p37 subunit that can serve to amplify the apoptotic response (3-6). Cleaved caspase-9 further processes other caspase members, including caspase-3 and caspase-7, to initiate a caspase cascade, which leads to apoptosis (7-10).

$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Human DFF45 and its mouse homologue ICAD function in normal cells as chaperones for caspase-activated deoxyribonuclease (DFF40 or CAD) during its synthesis (1). The association of DFF45 (or its isoform DFF35) with DFF40 inhibits the DNAse activity of the latter (1-4). In vitro, DFF45 has been shown to be the target of several caspases, including caspase-3, -6, -7, -8 and granzyme B (3). In vivo, caspase-3 is believed to be the primary enzyme responsible for processing DFF45 and release of its carboxy-terminal fragment (3,5). The cleavage of DFF45 inactivates its inhibitory function on DFF40 and causes nuclear DNA degradation by DFF40, leading to cell death (6,7).

$303
100 µl
APPLICATIONS
REACTIVITY
D. melanogaster

Application Methods: Immunofluorescence (Immunocytochemistry), Western Blotting

Background: Cell death in the fruit fly Drosophila melanogaster is regulated by many of the same stimuli as mammalian cell death (1). The Drosophila genome contains seven caspase genes; three encode initiator caspases, and four encode effector caspases (reviewed in (2)). The Drosophila effector caspase, death caspase-1 (Dcp-1), is a critical executioner of apoptosis. It is involved in the proteolytic cleavage of many key proteins, such as the nuclear enzyme poly (ADP-ribose) polymerase (PARP). The activation of Dcp-1 requires proteolytic processing of its inactive zymogen into active p22 and p13 fragments (3). Comparison of the in vivo activity between DrICE and Dcp-1 has shown that DrICE is a more effective inducer of apoptosis than Dcp-1, which instead plays a role in determining the rate of cell death (4).