title: Helicase-DNA polymerase interaction is critical to initiate leading-strand DNA synthesis.
abstract: Interactions between gene 4 helicase and gene 5 DNA polymerase (gp5) are crucial for leading-strand DNA synthesis mediated by the replisome of bacteriophage T7. Interactions between the two proteins that assure high processivity are known but the interactions essential to initiate the leading-strand DNA synthesis remain unidentified. Replacement of solution-exposed basic residues (K587, K589, R590, and R591) located on the front surface of gp5 with neutral asparagines abolishes the ability of gp5 and the helicase to mediate strand-displacement synthesis. This front basic patch in gp5 contributes to physical interactions with the acidic C-terminal tail of the helicase. Nonetheless, the altered polymerase is able to replace gp5 and continue ongoing strand-displacement synthesis. The results suggest that the interaction between the C-terminal tail of the helicase and the basic patch of gp5 is critical for initiation of strand-displacement synthesis. Multiple interactions of T7 DNA polymerase and helicase coordinate replisome movement.
authors: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
authors: Huidong
authors: H
authors: Zhang
authors: Seung-Joo
authors: SJ
authors: Lee
authors: Bin
authors: B
authors: Zhu
authors: Ngoc Q
authors: NQ
authors: Tran
authors: Stanley
authors: S
authors: Tabor
authors: Charles C
authors: CC
authors: Richardson
references: EMBO J. 2004 Sep 1;23(17):3452-61
references: 15297882
references: Mol Cell. 2007 Aug 17;27(4):527-38
references: 17707226
references: J Mol Biol. 2002 Aug 30;321(5):807-19
references: 12206763
references: Proc Natl Acad Sci U S A. 1995 Jul 3;92(14):6339-43
references: 7603992
references: Mol Cell. 2005 Sep 16;19(6):805-15
references: 16168375
references: J Biol Chem. 1997 Jul 18;272(29):18425-33
references: 9218486
references: Nature. 2005 May 19;435(7040):370-3
references: 15902262
references: Cell. 2000 Jun 9;101(6):589-600
references: 10892646
references: Annu Rev Biochem. 2005;74:283-315
references: 15952889
references: Nature. 1998 Jan 15;391(6664):251-8
references: 9440688
references: Nature. 2006 Feb 2;439(7076):621-4
references: 16452983
references: J Biol Chem. 2006 Apr 21;281(16):10653-6
references: 16421093
references: FEMS Microbiol Rev. 2006 May;30(3):321-81
references: 16594962
references: J Biol Chem. 2006 Sep 1;281(35):25841-9
references: 16807231
references: Biochim Biophys Acta. 2010 May;1804(5):1094-112
references: 19665592
references: Annu Rev Biochem. 2001;70:181-208
references: 11395406
references: J Virol. 2009 Sep;83(17):8418-27
references: 19535436
references: J Biol Chem. 1987 Nov 25;262(33):16212-23
references: 3316214
references: Proc Natl Acad Sci U S A. 2004 May 11;101(19):7264-9
references: 15123793
references: Proc Natl Acad Sci U S A. 2011 Mar 1;108(9):3584-9
references: 21245349
references: J Biol Chem. 2009 Oct 30;284(44):30339-49
references: 19726688
references: Proc Natl Acad Sci U S A. 2007 Mar 27;104(13):5312-7
references: 17369350
references: Mol Cell. 2007 Aug 17;27(4):539-49
references: 17707227
references: J Biol Chem. 2006 Sep 1;281(35):25831-40
references: 16807232
references: J Mol Biol. 2006 Jul 14;360(3):667-77
references: 16777142
references: Proc Natl Acad Sci U S A. 2005 Apr 5;102(14):5096-101
references: 15795374
references: Proc Natl Acad Sci U S A. 2004 Jun 1;101(22):8289-94
references: 15148377
references: Annu Rev Biochem. 2009;78:205-43
references: 19298182
references: Biochemistry. 1991 Jan 15;30(2):511-25
references: 1846298