Intracellular proteins interferon

Loeb, K. R. and Haas, A. L. The interferon-inducible 15-kDa ubiquitin homolog conjugates to intracellular proteins, / Biol Chem 1992, 267, 7806-7813. 

It is known from the interferon-inducible ubiquitin cross-reactive protein (UCRP) that it is conjugated to a small subset of intracellular proteins probably targeting them to the cytoskeleton (Loeb and Haas, 1994). 

Interferon. Any of a family of glycoproteins that exert virus-nonspecific but host-specific antiviral activity by inducing the transcription of cellular genes coding for antiviral proteins that selectively inhibit the synthesis of viral RNA and proteins. Interferons have immunoregulatory functions and can inhibit the growth of nonviral intracellular parasites. 

Pharmacology Interferons bind to specific receptors on the cell surface, initiating intracellular signaling via a complex cascade of protein-protein interactions and... 

The leptin signal is transduced by a mechanism also used by receptors for interferon and growth factors, the JAIC-STAT system (Fig. 23-34 see Fig. 12-9). The leptin receptor, which has a single transmembrane segment, dimerizes when leptin binds to the extracellular domain of two monomers. Both monomers are phos-phorylated on a Tyr residue of the intracellular domain by a Janus kinase (JAK). The -Tyr residues become docking sites for three proteins that are signal transducers and activators of transcription (STATs 3, 5, and 6, sometimes called fat-STATS). The docked STATs are then phosphorylated on Tyr residues by the... 

Proteolytic enzymes such as proteases and peptidases are ubiquitous throughout the body. Sites capable of extensive peptide and protein metabolism are not only limited to the liver, kidneys, and gastrointestinal tissue, but also include the blood and vascular endothelium as well as other organs and tissues. As proteases and peptidases are also located within cells, intracellular uptake is per se more an elimination rather than a distribution process [13]. While peptidases and proteases in the gastrointestinal tract and in lysosomes are relatively unspecific, soluble peptidases in the interstitial space and exopeptidases on the cell surface have a higher selectivity and determine the specific metabolism pattern of an organ. The proteolytic activity of subcutaneous tissue, for example, results in a partial loss of activity of SC compared to IV administered interferon-y. 

Interferon a Induction of celiuiar enzymes that interfere with virai protein synthesis Intracellular half-life of cidofovir diphosphate is 17-30 hours. Hepatitis B and C, human herpesvirus 8, papiiioma-virus 2-3... 

Interferons represent a class of proteins with various biological properties.338339 These include the ability to inhibit intracellular replication of viruses and certain parasites,340 the ability to inhibit replication of certain types of tumor cells in vitro, 41 and the ability to modulate immune responses in vitro and in vivo in a positive or negative manner.339 Of the interferons, interferon-y (IFN-y) is thought to be a more effective immunomodulary agent and a more effective inhibitor of division of certain tumor cells in vitro than other interferons.339 One mechanism of IFN-y-mediated growth inhibition is the stimulation of cellular oxidation of tryptophan by indoleamine 2,3-dioxygenase.342 343... 

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