       Document 0297
 DOCN  M9460297
 TI    Alternative modes of polymerization distinguish the subunits of equine
       infectious anemia virus reverse transcriptase.
 DT    9404
 AU    Wohrl BM; Howard KJ; Jacques PS; Le Grice SF; Division of Infectious
       Diseases, Case Western Reserve University; School of Medicine,
       Cleveland, Ohio 44106.
 SO    J Biol Chem. 1994 Mar 18;269(11):8541-8. Unique Identifier : AIDSLINE
       MED/94179245
 AB    A comparative study of recombinant 51- and 66-kDa subunits comprising
       equine infectious anemia virus reverse transcriptase (EIAV RT) is
       reported. Both polypeptides sedimented as stable homodimers (molecular
       mass, 102 and 132 kDa, respectively) when analyzed by rate sedimentation
       through glycerol gradients. Consistent with their dimer composition,
       each preparation displayed considerable levels of both RNA- and
       DNA-dependent DNA polymerase activity on different homopolymeric
       template/primer combinations. However, a detailed analysis of the
       polymerization products indicated qualitative differences. Whereas p66
       EIAV RT proceeded essentially unimpaired along both RNA and DNA
       templates, p51-catalyzed DNA synthesis was interrupted close to or in
       the immediate vicinity of the primer. A series of programmed 2-step
       polymerization reactions suggests that p51 EIAV RT enters an abortive
       mode of polymerization. Duplication of this observation with p51 human
       immunodeficiency virus-1 RT, together with recent observations from
       murine RT, suggests that lack of a ribonuclease H domain and loss of
       contact with the nascent product from the polymerase active center have
       profound consequences on the mode of polymerization.
 DE    Base Sequence  Comparative Study  DNA Polymerases/*METABOLISM  DNA
       Primers  Electrophoresis, Polyacrylamide Gel  Human  Infectious Anemia
       Virus, Equine/*ENZYMOLOGY  Macromolecular Systems  Molecular Sequence
       Data  Molecular Weight  Recombinant Proteins/CHEMISTRY/METABOLISM
       Reverse Transcriptase/*CHEMISTRY/ISOLATION & PURIF/*METABOLISM
       Substrate Specificity  Support, Non-U.S. Gov't  Support, U.S. Gov't,
       P.H.S.  Templates  JOURNAL ARTICLE

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

