CASP8 & FADD-like apoptosis regulator; cellular FLICE-like inhibitory protein; c-FLIP; caspase-8-related protein; casper; caspase-like apoptosis regulatory protein; CLARP; MACH-related inducer of toxicity; MRIT; caspase homolog; CASH; inhibitor of FLICE; I-FLICE; FADD-like antiapoptotic molecule 1; FLAME-1; usurpin (CFLAR, CASH, CASP8AP1, CLARP, MRIT)

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Function

apoptosis regulator protein
may function as a link between cell survival & cell death pathways in mammalian cells
acts as an inhibitor of TNFRSF6 mediated apoptosis
a proteolytic fragment (p43) is likely retained in the death-inducing signaling complex (DISC) thereby blocking further recruitment & processing of caspase-8 at the complex
full length & shorter isoforms have been shown either to induce apoptosis or to reduce TNFRSF-triggered apoptosis
lacks enzymatic (caspase) activity
proteolytically processed; probably by caspase-8
- processing likely occurs at the DISC & generates subunits p43 & p12
TNFRSF6 stimulation triggers recruitment to the death-inducing signaling complex (DISC) formed by TNFRSF6, FADD & caspase-8
a proteolytic fragment (p43) stays associated with the DISC
also interacts with caspase-10, caspase-3, TRAF1, TRAF2 & Bcl-X(L) (in vitro)
interacts with HBV protein X

named isoforms=14

widely expressed
higher expression in skeletal muscle, pancreas, heart, kidney, placenta, & peripheral blood leukocytes
detected in diverse cell lines
isoform 8 is predominantly expressed in testis & skeletal muscle
repressed by IL-2 after TCR stimulation, during progression to the S-phase of the cell cycle
overexpressed in some cancers