HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wang, C.-C. Articles by Karam, J. D. Search for Related Content PubMed PubMed Citation Articles by Wang, C.-C. Articles by Karam, J. D. Social Bookmarking                      What's this?

Volume 272, Number 28, Issue of July 11, 1997 pp. 17703-17710
©1997 by The American Society for Biochemistry and Molecular Biology, Inc.

Evolution of RNA-binding Specificity in T4 DNA Polymerase

(Received for publication, January 10, 1997, and in revised form, May 12, 1997)

From the Department of Biochemistry, SL43, Tulane University School of Medicine, New Orleans, Louisana 70112

DNA polymerase of phage T4 (T4 gp43), an essential component of the T4 DNA replicase, is a multifunctional single-chained (898-amino acid) protein that catalyzes the highly accurate synthesis of DNA in phage replication. The enzyme functions both as a DNA-binding replication protein and as a sequence-specific RNA-binding autogenous translational repressor. We have utilized a phylogenetic approach to study the relationships between the two nucleic acid-binding functions of the protein. We found that autogenous translational control of gp43 biosynthesis has been conserved in phage RB69, a distant relative of T4, although we also found that the RB69 system differs from its T4 counterpart in two regards: (a) nucleotide sequence and predicted secondary structure of the RNA target (translational operator), and (b) RNA specificity of the protein. T4 gp43 is specific to the RNA operator sequence of the T4 genome whereas RB69 gp43 can bind and repress operator RNA from both phages equally well. In studies with T4-RB69 gp43 chimeras, we mapped T4 gp43 RNA-binding specificity to a protein segment that also harbors important determinants for DNA binding and the polymerase catalytic function. Our results suggest that RNA functions as a regulator of both the dosage and activity of this DNA replication enzyme.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				I. K. O. Cann, K. R. Amaya, M. W. Southworth, and F. B. Perler Bacteriophage-Based Genetic System for Selection of Nonsplicing Inteins Appl. Envir. Microbiol., May 1, 2004; 70(5): 3158 - 3162. [Abstract] [Full Text] [PDF]

				E. S. Miller, E. Kutter, G. Mosig, F. Arisaka, T. Kunisawa, and W. Ruger Bacteriophage T4 Genome Microbiol. Mol. Biol. Rev., March 1, 2003; 67(1): 86 - 156. [Abstract] [Full Text] [PDF]

				V. M. Petrov, S.-s. Ng, and J. D. Karam Protein Determinants of RNA Binding by DNA Polymerase of the T4-related Bacteriophage RB69 J. Biol. Chem., August 30, 2002; 277(36): 33041 - 33048. [Abstract] [Full Text] [PDF]

				V. M. Petrov and J. D. Karam RNA determinants of translational operator recognition by the DNA polymerases of bacteriophages T4 and RB69 Nucleic Acids Res., August 1, 2002; 30(15): 3341 - 3348. [Abstract] [Full Text] [PDF]

				A. R. Pavlov and J. D. Karam Nucleotide-sequence-specific and non-specific interactions of T4 DNA polymerase with its own mRNA Nucleic Acids Res., December 1, 2000; 28(23): 4657 - 4664. [Abstract] [Full Text] [PDF]

				L.-S. Yeh, T. Hsu, and J. D. Karam Divergence of a DNA Replication Gene Cluster in the T4-Related Bacteriophage RB69 J. Bacteriol., April 15, 1998; 180(8): 2005 - 2013. [Abstract] [Full Text]

				A. Bebenek, H. K. Dressman, G. T. Carver, S.-s. Ng, V. Petrov, G. Yang, W. H. Konigsberg, J. D. Karam, and J. W. Drake Interacting Fidelity Defects in the Replicative DNA Polymerase of Bacteriophage RB69 J. Biol. Chem., March 23, 2001; 276(13): 10387 - 10397. [Abstract] [Full Text] [PDF]