• Login as Editor
    View Item 
    •   Yeshiva Academic Institutional Repository
    • Albert Einstein College of Medicine (AECOM)
    • Albert Einstein College of Medicine: Doctoral Dissertations
    • View Item
    •   Yeshiva Academic Institutional Repository
    • Albert Einstein College of Medicine (AECOM)
    • Albert Einstein College of Medicine: Doctoral Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    ROLE OF SECONDARY STRUCTURE IN DETERMINING AN ACTIVE PRIMOSOME ASSEMBLY SITE

    Thumbnail
    Date
    1984
    Author
    SOELLER, WALTER CARL
    Metadata
    Show full item record
    Abstract
    Discrete, single-stranded DNA segments from 0X174 viral DNA strands and from the H (pas-BH) and L (pas-BL) strands of pBR322 and ColE1 DNAs specifically induce ATP hydrolysis by E. coli replication factor Y (protein n'). These same segments have the potential to form higher order DNA structures and function as assembly sites for a host-encoded, multi-enzyme complex (the primosome) whose components were previously shown to be required for priming DNA synthesis on 0X174 viral strands.;In order to identify important features of these primosome assembly sites with respect to their interaction with factor Y, I have studied the in vitro phenotypes of mutant pas sequences generated by in vitro mutagenesis procedures.;Characterization of the single base substitution mutations in pas-BL resolved them into two classes. Class I mutants exhibited wild-type levels of factor Y ATPase effector activity and origin function. These mutants represented either nonessential bases or regions acting as spacer sequences. Class II mutants were completely inactive as effectors for factor Y ATPase activity in the presence of low concentrations of Mg('2+). However, increasing Mg('2+) concentrations specifically restored the effector activity of these mutants. Mn('2+) and spermidine could substitute for Mg('2+) in producing this differential effect on class II mutant DNAs. Since these ligands are known to affect the stability of duplex DNA, these results implied that duplex DNA played some role in the interaction of factor Y with pas sequences.;With the intent of obtaining evidence of base pairing within pas-BL, multiple base substitution mutants and their revertants were examined. Mutant DNAs which had two or three base alterations in the pas-BL sequence were generally inactive both as factor Y ATPase effectors and as primosome-dependent, complementary strand origins of DNA replication (class III mutations). Revertants of these mutants were isolated using a plaque morphology assay. Some of these reversion events occurred in second sites within the pas sequence in a manner that strongly suggested that base pairing was essential among certain pas residues in the formation of an active primosome assembly site. These results indicated that the DNA sequence was important primarily for determining the compacted, higher order structure of a pas and that double helical, base-paired DNA played an important role in forming this higher order structure.
    Permanent Link(s)
    https://yulib002.mc.yu.edu/login?url=http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqm&rft_dat=xri:pqdiss:8421637
    https://hdl.handle.net/20.500.12202/2958
    Collections
    • Albert Einstein College of Medicine: Doctoral Dissertations [1674]

    Yeshiva University Libraries copyright © 2021  DuraSpace
    YAIR Self-Deposit | YAIR User's Guide | Take Down Policy | Contact Us
    Yeshiva University
     

     

    Browse

    AllCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Login as Editor

    Statistics

    View Usage Statistics

    Yeshiva University Libraries copyright © 2021  DuraSpace
    YAIR Self-Deposit | YAIR User's Guide | Take Down Policy | Contact Us
    Yeshiva University