Open AccessGenetic strategy for analyzing specificity of dimer formation: Escherichia coli cyclic AMP receptor protein mutant altered in its dimerization specificity.
Author(s) -
J. Keith Joung,
Eugene H. Chung,
Glenn F. King,
Channing Yu,
Andrew S. Hirsh,
Ann Hochschild
Publication year - 1995
Publication title -
genes and development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.136
H-Index - 438
eISSN - 1549-5477
pISSN - 0890-9369
DOI - 10.1101/gad.9.23.2986
Subject(s) - mutant , biology , escherichia coli , mutant protein , camp receptor protein , biochemistry , mutation , amino acid , genetic screen , microbiology and biotechnology , gene , promoter , gene expression
Many transcriptional regulators function in homo- or heterodimeric combinations. The same protein can carry out distinct regulatory functions depending on the partner with which it associates. Here, we describe a mutant of the Escherichia coli cAMP receptor protein (CRP) that has an altered dimerization specificity; that is, mutant/mutant homodimers form preferentially over wild-type/mutant heterodimers. CRP dimerization involves the formation of a parallel coiled-coil structure, and our CRP mutant bears an amino acid substitution affecting the first "d" position residue within the alpha-helix that mediates CRP dimerization. The genetic strategy we used to isolate this CRP altered dimerization specificity (ADS) mutant is generalizable and could be utilized to isolate ADS mutants of other dimeric transcriptional regulators.