Characterization of antibodies specific for the caspase cleavage site on poly(ADP-ribose) polymerase: specific detection of apoptotic fragments and mapping of the necrotic fragments of poly(ADP-ribose)polymerase

ABSTRACTHuntington disease (HD) is a progressive neurodegenerative disease that initially affects the striatum leading to changes in behavior and loss of motor coordination. It is caused by an expansion in the polyglutamine repeat at the N-terminus of huntingtin (HTT) that leads to aggregation of mutant HTT. The loss of wildtype function, in combination with the toxic gain of function mutation, initiates various cell death pathways. Wildtype and mutant HTT are regulated by different post-translational modifications that can positively or negatively regulate their function or toxicity. In particular, we have previously shown that caspase cleavage of mutant HTT at amino acid position aspartate 586 (D586) by caspase-6 is critical for the pathogenesis of the disease in an HD mouse model. Herein, we describe the identification of a new caspase cleavage site at position D572 that is mediated by caspase-1. Inhibition of caspase-1 also inhibits cleavage at D586 through inhibition of caspase-6. Inhibition of caspase cleavage at D572 significantly decreases mutant HTT aggregation and significantly increased the turnover of soluble mutant HTT. This suggests that caspase-1 may be a viable target to inhibit caspase cleavage of mutant HTT at both D572 and D586 to promote mutant HTT clearance.

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The role of the N-terminal caspase cleavage site in the nucleoprotein of influenza A virus in vitro and in vivo

Archives of Virology ◽

10.1007/s00705-007-0003-8 ◽

2007 ◽

Vol 153 (3) ◽

pp. 427-434 ◽

Cited By ~ 10

Author(s):

A. S. Lipatov ◽

H.-L. Yen ◽

R. Salomon ◽

H. Ozaki ◽

E. Hoffmann ◽

...

Keyword(s):

Influenza A Virus ◽

Cleavage Site ◽

Influenza A ◽

Caspase Cleavage ◽

Caspase Cleavage Site

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Effect of caspase cleavage-site phosphorylation on proteolysis

Biochemical Journal ◽

10.1042/bj20021901 ◽

2003 ◽

Vol 372 (1) ◽

pp. 137-143 ◽

Cited By ~ 32

Author(s):

József TÖZSÉR ◽

Péter BAGOSSI ◽

Gábor ZAHUCZKY ◽

Suzanne I. SPECHT ◽

Eva MAJEROVA ◽

...

Keyword(s):

Cleavage Site ◽

Apoptotic Cell ◽

Phosphorylation Site ◽

Substantial Effect ◽

Cellular Protein ◽

Cleavage Sites ◽

Potential Phosphorylation Site ◽

Caspase Cleavage ◽

Protein Substrates ◽

Caspase Cleavage Site

Caspases are important mediators of apoptotic cell death. Several cellular protein substrates of caspases contain potential phosphorylation site(s) at the cleavage-site region, and some of these sites have been verified to be phosphorylated. Since phosphorylation may affect substantially the substrate susceptibility towards proteolysis, phosphorylated, non-phosphorylated and substituted oligopeptides representing such cleavage sites were studied as substrates of apoptotic caspases 3, 7 and 8. Peptides containing phosphorylated serine residues at P4 and P1′ positions were found to be substantially less susceptible towards proteolysis as compared with the serine-containing analogues, while phosphoserine at P3 did not have a substantial effect. P1 serine as well as P1-phosphorylated, serine-containing analogues of an oligopeptide representing the poly(ADP-ribose) polymerase cleavage site of caspase-3 were not hydrolysed by any of these enzymes, whereas the P1 aspartate-containing peptides were efficiently hydrolysed. These findings were interpreted with the aid of molecular modelling. Our results suggest that cleavage-site phosphorylation in certain positions could be disadvantageous or detrimental with respect to cleavability by caspases. Cleavage-site phosphorylation may therefore provide a regulatory mechanism to protect substrates from caspase-mediated degradation.

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Identification of Caspase-cleavage site in the apoptosis sup-pressor protein P49 from the Spodoptera littoralis nucleopoly-hedrovirus

Chinese Science Bulletin ◽

10.1360/02wc0099 ◽

2003 ◽

Vol 48 (8) ◽

pp. 804

Author(s):

Zifei PEI

Keyword(s):

Spodoptera Littoralis ◽

Cleavage Site ◽

Caspase Cleavage ◽

Caspase Cleavage Site

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Rescue of Infectious Recombinant Hazara Nairovirus from cDNA Reveals the Nucleocapsid Protein DQVD Caspase Cleavage Motif Performs an Essential Role other than Cleavage

Journal of Virology ◽

10.1128/jvi.00616-19 ◽

2019 ◽

Vol 93 (15) ◽

Cited By ~ 7

Author(s):

J. Fuller ◽

R. A. Surtees ◽

G. S. Slack ◽

J. Mankouri ◽

R. Hewson ◽

...

Keyword(s):

Life Cycle ◽

Human Disease ◽

Nucleocapsid Protein ◽

Cleavage Site ◽

Critical Role ◽

Productive Infection ◽

Wild Type Virus ◽

Reverse Genetic ◽

Caspase Cleavage ◽

Caspase Cleavage Site

ABSTRACT The Nairoviridae family of the Bunyavirales order comprises tick-borne, trisegmented, negative-strand RNA viruses, with several members being associated with serious or fatal diseases in humans and animals. A notable member is Crimean-Congo hemorrhagic fever virus (CCHFV), which is the most widely distributed tick-borne pathogen and is associated with devastating human disease, with case fatality rates averaging 30%. Hazara virus (HAZV) is closely related to CCHFV, sharing the same serogroup and many structural, biochemical, and cellular properties. To improve understanding of HAZV and nairovirus multiplication cycles, we developed, for the first time, a rescue system permitting efficient recovery of infectious HAZV from cDNA. This system now allows reverse genetic analysis of nairoviruses without the need for high-level biosafety containment, as is required for CCHFV. We used this system to test the importance of a DQVD caspase cleavage site exposed on the apex of the HAZV nucleocapsid protein arm domain that is cleaved during HAZV infection, for which the equivalent DEVD sequence was recently shown to be important for CCHFV growth in tick but not mammalian cells. Infectious HAZV bearing an uncleavable DQVE sequence was rescued and exhibited growth parameters equivalent to those of wild-type virus in both mammalian and tick cells, showing this site was dispensable for virus multiplication. In contrast, substitution of the DQVD motif with the similarly uncleavable AQVA sequence could not be rescued despite repeated efforts. Together, these results highlight the importance of this caspase cleavage site in the HAZV life cycle but reveal the DQVD sequence performs a critical role aside from caspase cleavage. IMPORTANCE HAZV is classified within the Nairoviridae family with CCHFV, which is one of the most lethal human pathogens in existence, requiring the highest biosafety level (BSL) containment (BSL4). In contrast, HAZV is not associated with human disease and thus can be studied using less-restrictive BSL2 protocols. Here, we report a system that is able to rescue HAZV from cDNAs, thus permitting reverse genetic interrogation of the HAZV replication cycle. We used this system to examine the role of a caspase cleavage site, DQVD, within the HAZV nucleocapsid protein that is also conserved in CCHFV. By engineering mutant viruses, we showed caspase cleavage at this site was not required for productive infection and this sequence performs a critical role in the virus life cycle aside from caspase cleavage. This system will accelerate nairovirus research due to its efficiency and utility under amenable BSL2 protocols.

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Caspase Cleavage of Keratin 18 and Reorganization of Intermediate Filaments during Epithelial Cell Apoptosis

The Journal of Cell Biology ◽

10.1083/jcb.138.6.1379 ◽

1997 ◽

Vol 138 (6) ◽

pp. 1379-1394 ◽

Cited By ~ 429

Author(s):

Carlos Caulín ◽

Guy S. Salvesen ◽

Robert G. Oshima

Keyword(s):

Intermediate Filaments ◽

Cleavage Site ◽

Uv Light ◽

Tail Domain ◽

Proteolytic Fragment ◽

Intermediate Filament Proteins ◽

Caspase Cleavage ◽

Structural Cell ◽

Caspase 6

Keratins 8 (K8) and 18 (K18) are major components of intermediate filaments (IFs) of simple epithelial cells and tumors derived from such cells. Structural cell changes during apoptosis are mediated by proteases of the caspase family. During apoptosis, K18 IFs reorganize into granular structures enriched for K18 phosphorylated on serine 53. K18, but not K8, generates a proteolytic fragment during drug- and UV light–induced apoptosis; this fragment comigrates with K18 cleaved in vitro by caspase-6, -3, and -7. K18 is cleaved by caspase-6 into NH2-terminal, 26-kD and COOH-terminal, 22-kD fragments; caspase-3 and -7 additionally cleave the 22-kD fragment into a 19-kD fragment. The cleavage site common for the three caspases was the sequence VEVD/A, located in the conserved L1-2 linker region of K18. The additional site for caspases-3 and -7 that is not cleaved efficiently by caspase-6 is located in the COOH-terminal tail domain of K18. Expression of K18 with alanine instead of serine at position 53 demonstrated that cleavage during apoptosis does not require phosphorylation of serine 53. However, K18 with a glutamate instead of aspartate at position 238 was resistant to proteolysis during apoptosis. Furthermore, this cleavage site mutant appears to cause keratin filament reorganization in stably transfected clones. The identification of the L1-2 caspase cleavage site, and the conservation of the same or very similar sites in multiple other intermediate filament proteins, suggests that the processing of IFs during apoptosis may be initiated by a similar caspase cleavage.

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