Document 0061
 DOCN  M9550061
 TI    In vivo decay kinetic parameters of hammerhead ribozymes.
 DT    9505
 AU    Sioud M; Opstad A; Zhao JQ; Levitz R; Benham C; Drlica K; Institute of
       Immunology and Rheumatology, Rikshospitalet, Oslo,; Norway.
 SO    Nucleic Acids Res. 1994 Dec 25;22(25):5571-5. Unique Identifier :
       AIDSLINE MED/95140617
 AB    Ribozymes offer a potentially important way to inactivate intracellular
       RNA from almost any gene whose nucleotide sequence is known. Recently,
       we found that hammerhead ribozymes directed against mRNA of tumour
       necrosis factor alpha (TNF alpha) and its derivatives, preferentially
       bind to a cellular protein(s). To better understand the effect of
       different 3'-terminal hairpins on ribozyme stability as well as their
       effect on the protein binding to the ribozyme, a mathematical treatment
       of the decay of three TNF alpha ribozymes that differed at their 3' ends
       was performed. One ribozyme contained a 3'-terminal hairpin derived from
       a transcription terminator of bacteriophage T7, another contained the
       same hairpin but modified to be highly enriched for G+C nucleotides, and
       a third lacked a hairpin. The TNF alpha ribozyme decay had two kinetic
       components. The slow component exhibited exponential decay with a half
       life of approximately 250 h in all cases. The 3'-terminal hairpin has no
       significant effect on this component. This slow phase accounted for
       60-80% of ribozyme decay. The rapid phase also exhibited exponential
       decay. For this phase, a 3'-terminal hairpin roughly doubled the
       half-life (1.7-3.4). The slow phase of degradation was about three times
       faster for a ribozyme directed at the integrase mRNA of human
       immunodeficiency virus-1 than that seen with the TNF alpha ribozyme.
       Taken together, these results suggest that the ribozyme population is
       initially sensitive to degradation, with the presence of a hairpin
       provides some protection, and indicate that the addition of the hairpin
       to the ribozyme did not prevent the in vivo additional stabilizing
       effect of the protein(s).
 DE    Base Sequence  Cell Line  Human  Kinetics  Molecular Sequence Data
       Nucleic Acid Denaturation  RNA, Catalytic/*CHEMISTRY  Support, Non-U.S.
       Gov't  Support, U.S. Gov't, P.H.S.  Transfection  Tumor Necrosis
       Factor/*GENETICS  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).