Human RNase

DNA- binding aptamers have been designed to bind to mRNA, g-quad-ruplexes, Tenascin-C, a protein found in the tumor matrix, and to thrombin. Aptamers have been selected as inhibitors of HIV-1 integrase, human RNase Hl, human pro-urokinase " and for the design of molecular beacons. An allosteric aptamer has been designed for binding as a colorimetric probe for cocaine. ... 

Uncommon caibohydrate-pepUde linkages identified in (a) human RNase 2 and (b) proteinase I of D. discoideum... 

Fig. 1. The dock and lock" system, (a) Two mutated tragments of human RNase I spontaneously form a complex where complimentary cysteines form a disulphate bond, (b), purified Ad-liposome can be coupled to a Cys-tagged targeting protein of choice.

Some members of the human RNase A superfamily of proteins are known to have host defense activities (reviewed in ref. 9). These include, for example, two of the eosinophil cytotoxic granular proteins, eosinophil cationic protein (ECP), and eosinophil-derived neurotoxin (EDN) (10). Angiogenin, a protein 65 % homologous to pancreatic RNase (11,12) that was originally isolated on the basis of its angiogenic activity (13), is a potent inhibitor of protein synthesis in the rabbit reticulocyte lysate (14) and when injected into Xenopus oocytes (15). We have therefore sought to fuse RNases to MAbs to evaluate their usefulness as immunotoxins (16,17). 

Ridanpaa M, van Eenennaam H, Pelin K et al. Mutations in the RNA component of RNase MRP cause a pleiotropic human disease, cartilage-hair hypoplasia. Cell 2001 104J2] 195-203. 

An example of enzyme depletion is the ribonuclease inhibitor isolated from human placenta by Blackburn, Wilson Moore. This protein forms a 1 1 complex with bovine pancreatic RNase A and is a noncompetitive... 

Like all other retroviruses, human immunodeficiency virus type 1 (HIV-1) contains the multifunctional enzyme reverse transcriptase (RT). Retroviral RTs have a DNA polymerase activity that can use either an RNA or a DNA template and an RNase H activity. HIV-1 RT is essential for the conversion of single-stranded viral RNA into a linear double-stranded DNA that is subsequently integrated into the host cell chromosomes [1-4]. In this conversion process HIV-1 RT catalyzes the incorporation of approximately... 

Lacey SF, Reardon JE, Furfine ES, Kunkel , Bebenek K, Eckert KA, et al. Biochemical studies on the reverse transcriptase and RNase H activities from human immunodeficiency virus strains resistant to 3 -azido-3 -deoxythymidine. JBiol Chem 1992 267 15789-15794. 

Tisdale M, Schulze T, Larder BA, Moelling K. Mutations within the RNase H domain of human immunodeficiency virus type 1 reverse transcriptase abolish virus infectivity. J Gen Virol 1991 72 59-66. 

Smith JS, Roth MJ. Purification and characterization of an active human immunodeficiency virus type 1 RNase H domain. J Virol 1993 67 4037-4049. 

Loya S, Tal R, Kashman Y, Hizi A. Illimaquinone, a selective inhibitor of the RNase H activity of human immunodeficiency vims type 1 reverse transcriptase. Antimicrob Agents Chemother 1990 34 2009-2012. 

Loya S, Hizi A. The interaction of illimaquinone, a selective inhibitor of the RNase H activity, with the reverse transcriptases of human immunodeficiency and murine leukemia retroviruses. J Biol Chem 1993 268 9323-9328. 

This is converted to an inactive phosphorylated form by a dsRNA-dependent protein kinase205 (Fig. 31-10). The protein kinase also appears to be an interferon-induced protein206 as is the oligo(2 -5 A)-activated RNAse indicated in Fig. 31-10.207 Interferons have effects other than inducing the antiviral state. Thus, human IFN-(32 is identical to a B-cell differentiation factor.208 Both IFN-a and IFN-(3 have antigrowth activity and are currently in use for treatment of some forms of cancer as well as for viral infections.209... 

What is the driving force for protein adsorption Is the adsorption driven by overall energetic (enthalpic) interactions or does the entropic contribution prevail Do both entropic and enthalpic contributions play a major part in the adsorption process, the extent of each depending on the particular protein and surface in question An illuminating thermodynamic analysis given by Norde and Lyklema 62,66) for the adsorption of two different globular proteins (human serum albumin, HSA, and bovine pancreatic ribonuclease, RNase) on polystyrene latices will be presented. We believe this analysis has general validity. 

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