Lrp, a major regulatory protein in Escherichia coli, bends DNA and can organize the assembly of a higher-order nucleoprotein structure.
AUTOR(ES)
Wang, Q
RESUMO
Lrp (Leucine-responsive regulatory protein) is a global regulatory protein that controls the expression of many operons in Escherichia coli. One of those operons, ilvIH, contains six Lrp binding sites located within a several hundred base pair region upstream of the promoter region. Analysis of the binding of Lrp to a set of circularly permuted DNA fragments from this region indicates that Lrp induces DNA bending. The results of DNase I footprinting experiments suggest that Lrp binding to this region facilitates the formation of a higher-order nucleoprotein structure. To define more precisely the degree of bending associated with Lrp binding, one or two binding sites were separately cloned into a pBend vector and analyzed. Lrp induced a bend of approximately 52 degrees upon binding to a single binding site, and the angle of bending is increased to at least 135 degrees when Lrp binds to two adjacent sites. Lrp-induced DNA bending, and a natural sequence-directed bend that exists within ilvIH DNA, may be architectural elements that facilitate the assembly of a nucleoprotein complex.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=413487Documentos Relacionados
- Apoptin protein multimers form distinct higher-order nucleoprotein complexes with DNA
- Barrier-to-autointegration factor (BAF) bridges DNA in a discrete, higher-order nucleoprotein complex
- Higher-order structure of Saccharomyces cerevisiae chromatin.
- Higher-order structure of human mitotic chromosomes.
- Higher-order structure of long repeat chromatin.
