Characterization and selectivity of catalytic antibodies from human serum with RNase activity.
IgG purified from sera of several patients with systemic lupus erythematosus and hepatitis B are shown to present RNA hydrolyzing activities that are different from the weak RNase A-type activities found in the sera of healthy donors. Further investigation brings evidence for two intrinsic activities, one observed in low salt conditions and another specifically stimulated by Mg2+ions and distinguishable from human sera RNases. Cleavage of RNA substrates by the latter activity is not sequence-specific but sensitive to both subtle conformational and/or drastic folding changes, as evidenced by comparative analysis of couples of structurally well-studied RNA substrates. These include yeast tRNAAsp and its in vitro transcript and human mitochondrial tRNALys-derived in vitro transcripts. The discovery of catalytic antibodies with RNase activities is a first step towards creation of a new generation of tools for the investigation of RNA structure.
Vlassov
A
A
UPR 9002 du CNRS, Institut de Biologie Moléculaire et Cellulaire, 15, rue René Descartes, 67084 Strasbourg Cedex, France.
Florentz
C
C
Helm
M
M
Naumov
V
V
Buneva
V
V
Nevinsky
G
G
Giegé
R
R
D017151:Antibodies, Catalytic / Q000097:blood* / Q000737:chemistry; D001483:Base Sequence; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D006509:Hepatitis B / Q000097:blood / Q000201:enzymology / Q000276:immunology; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000201:enzymology / Q000276:immunology; D008274:Magnesium / Q000502:physiology; D008928:Mitochondria / Q000201:enzymology; D008969:Molecular Sequence Data; D011489:Protein Denaturation; D012349:RNA, Transfer, Asp / Q000378:metabolism; D012357:RNA, Transfer, Lys / Q000378:metabolism; D012260:Ribonucleases / Q000097:blood* / Q000737:chemistry; D012441:Saccharomyces cerevisiae; D012964:Sodium / Q000502:physiology; D013379:Substrate Specificity; D014158:Transcription, Genetic
D017151:Antibodies, Catalytic; D012349:RNA, Transfer, Asp; D012357:RNA, Transfer, Lys; D012964:Sodium; D012260:Ribonucleases; D008274:Magnesium