Identification of an N-terminal region of sigma 54 required for enhancer responsiveness

被引:36
作者
Syed, A
Gralla, JD
机构
[1] Univ Calif Los Angeles, Dept Biochem & Chem, Los Angeles, CA 90095 USA
[2] Univ Calif Los Angeles, Inst Mol Biol, Los Angeles, CA 90095 USA
关键词
D O I
10.1128/JB.180.21.5619-5625.1998
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Sigma 54 associates with bacterial core RNA polymerase and converts it into an enhancer-responsive enzyme. Deletion of the N-terminal 40 amino acids is known to result in loss of the ability to respond to enhancer binding proteins. In this work PCR mutagenesis and genetic screens were used to identify a small patch, from amino acids 33 to 37, that is required for proper response to activator in vivo. Site-directed single point mutants within this segment were constructed and studied. Two of these were defective in responding to the enhancer binding protein in vitro. The mutants could still direct the polymerase to bind to DNA and initiate transient melting. However, they failed in directing activator-dependent formation of a heparin-stable open complex. Thus, amino acid region 33 to 37 includes critical activation response determinants. This region overlaps the larger leucine patch negative-control region, suggesting that anti-inhibition and positive activation are closely coupled events.
引用
收藏
页码:5619 / 5625
页数:7
相关论文
共 32 条
[1]   THE PROKARYOTIC ENHANCER BINDING-PROTEIN NTRC HAS AN ATPASE ACTIVITY WHICH IS PHOSPHORYLATION AND DNA-DEPENDENT [J].
AUSTIN, S ;
DIXON, R .
EMBO JOURNAL, 1992, 11 (06) :2219-2228
[2]   A TEMPORALLY CONTROLLED SIGMA-FACTOR IS REQUIRED FOR POLAR MORPHOGENESIS AND NORMAL-CELL DIVISION IN CAULOBACTER [J].
BRUN, YV ;
SHAPIRO, L .
GENES & DEVELOPMENT, 1992, 6 (12A) :2395-2408
[3]   ACTIVATOR-INDEPENDENT FORMATION OF A CLOSED COMPLEX BETWEEN SIGMA-54-HOLOENZYME AND NIFH AND NIFU PROMOTERS OF KLEBSIELLA-PNEUMONIAE [J].
BUCK, M ;
CANNON, W .
MOLECULAR MICROBIOLOGY, 1992, 6 (12) :1625-1630
[4]   Two domains within sigma(N) (sigma(54)) cooperate for DNA binding [J].
Cannon, WV ;
Chaney, MK ;
Wang, XY ;
Buck, M .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1997, 94 (10) :5006-5011
[5]   Probing the assembly of transcription initiation complexes through changes in sigma(N) protease sensitivity [J].
Casaz, P ;
Buck, M .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1997, 94 (22) :12145-12150
[6]   ACTIVATION OF TRANSCRIPTION INITIATION FROM THE NAC PROMOTER OF KLEBSIELLA-AEROGENES [J].
FENG, JL ;
GOSS, TJ ;
BENDER, RA ;
NINFA, AJ .
JOURNAL OF BACTERIOLOGY, 1995, 177 (19) :5523-5534
[7]  
GUO Y, IN PRESS P NATL ACAD
[8]   DNA-binding determinants of sigma 54 as deduced from libraries of mutations [J].
Guo, YL ;
Gralla, JD .
JOURNAL OF BACTERIOLOGY, 1997, 179 (04) :1239-1245
[9]   ANALYSIS OF THE N-TERMINAL LEUCINE HEPTAD AND HEXAD REPEATS OF SIGMA-54 [J].
HSIEH, ML ;
GRALLA, JD .
JOURNAL OF MOLECULAR BIOLOGY, 1994, 239 (01) :15-24
[10]  
HSIEH ML, 1994, J BIOL CHEM, V269, P373