IL-ip converting enzyme

The enzyme that releases active IL-ip from its 31 kDa precursor has been identified and studied in detail. Termed IL-ip converting enzyme (ICE), it is a serine protease whose only known physiological substrate is the inactive IL-ip precursor. ICE cleaves this precursor between Asp 116 and Ala 117, releasing the active IL-ip. 

Fas, fragment apoptosis stimulator FADD, Fas-associated death domain FLICE, FADD-like Interleukin-Ibeta (IL-ip) converting enzyme. Click for human B-cell lymphoblasts producing constitutively Fas-Ugand (FasL) to kill Fas-receptor positive (FasR CIM" (cluster of differentiation) immune T cells (Klinker MW et al Front Immunol 2014 Apr 4. doi 10.3389/fimmu.2014.00144. 

Although several different proteinases can cleave the IL-ip precursor in vitro, the natural cleavage of the IL-ip precursor in macrophages and monocytes occurs via the action of a novel cysteine proteinase designated the IL-ip-converting enzyme. 

Watson RW, Rotstein OD, Parodo J, Bitar R, Marshall JC, William R, Watson G The IL-113-converting enzyme (caspase-1) inhibits apoptosis of inflammatory neutrophils through activation of IL-ip. J Immunol 1998 161 957-962. 

NEMO kinase (regulatory subunit IKKy), NFkB (nuclear factor kappa B lymphoma) essential modulator, inhibitor of kappa kinase gamma (IKKy). Protein kinase C-interacting protein p62/sequestosome-l, is activated by interleukin IL-IP in sequence, it activates of nuclear factor NFkB in TNFa-stimulated cells (Zotti T et al Mol Immunol 2014 58 27-31). NEMO promotes vFFlP (Fas-associated death domain-like interleukin-1-converting enzyme inhibitory protein) expression by Kaposi sarcoma associated herpesvirus (KSHV) (Tolani B et al J Virol 2014 March 26 PMID 24672029). 

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