Genome-wide screening and identification of novel proteolytic cleavage targets of caspase-8 and -10 in vitro

Abstract

Apoptosis executed by the mammalian caspase family plays a fundamental role in cellular homeostasis. Deregulation of this process is associated with several human diseases. The multimerization of ligand-induced death receptors results in the recruitment of the death inducing signaling complex and autocatalytic activation of initiator caspases, including caspase-8 and -10. However, it is still unclear how initiator caspases trigger and control the early apoptotic signaling pathways, partly because the downstream proteolytic cleavage targets of the initiator caspases are not completely known. Although it is known that a number of proteins are cleaved by various members of the caspase family, the identification of specific cleavage substrates of the initiator caspases 8 and 10, has been hindered by a lack of systematic and broadly applicable strategies for substrate identification. In the present study we constructed a mouse cDNA library and used it to perform a systematic, genomewide screen for novel in vitro substrates of caspase-8 and -10. From this, we successfully identified six putative caspase substrates, including five novel proteins (ABCF1, AKAP1, CPE, DOPEY1 and GOPC1) that may be targeted specifically by the initiator caspases 8 and 10 during the early stages of apoptosis. These findings may provide useful information for elucidating the apoptotic signaling pathways downstream of the death receptors.

Gene expression signature is shared by patients with Alzheimer’s disease and schizophrenia at the superior temporal gyrus

“…Four of the 55 genes, PEX14 , APOL2 , WARS , and DOPEY1 , appear in three brain regions. DOPEY1 is particularly interesting because its protein is a target for caspase 8 and 10 and may be involved in apoptosis and autophagy [13].…”

Cellular Mechanisms Controlling Caspase Activation and Function

“…(Kischkel et al 2001;Wang et al 2001;Sprick et al 2002;Fischer et al 2006;Bae et al 2008;Benkova et al 2009;Chen et al 2009). A recent paper by Wachmann and colleagues used in vitro dimerization assays to show that caspase-10 is also activated through induced proximity dimerization, as described for other initiator caspases (Wachmann et al 2010).…”

Specific proteolysis of the A-kinase-anchoring protein 149 at the Asp582 residue by caspases during apoptosis

“…As a result of a systematic and genome-wide screen, we have recently identified five novel putative substrates, including murine AKAP129, of initiator caspase-8 and -10 in vitro (25). In our study, we present evidence that AKAP149, a human protein homologous to mouse AKAP121, is a bona fide proteolytic target that is specifically cleaved by caspases during apoptosis in cells.…”