Target genes and structure of the direct repeats in the DNA-binding sequences of the response regulator PhoP in Streptomyces coelicolor.
Expression of genes belonging to the pho regulon in Streptomyces coelicolor is positively regulated (as shown by comparing the wild-type and a DeltaphoP mutant) by binding of the response regulator PhoP to 11-nt direct repeats (DRus). These sequences have been found in over 100 genes of Streptomyces coelicolor; 20 of them were cloned and the binding of PhoP(DBD) to most of their promoters has been shown by electrophoretic mobility shift assays. Deletion experiments showed that at least two DRus are required for proper binding of PhoP(DBD). Deletion of 1 nt leaving a 10-nt direct repeat reduced drastically binding of PhoP(DBD). Three different types of operators have been identified. Complex operators (class III) contain up to six DRus, some of them with poor conservation of the 11-nt consensus sequence, which however were protected by PhoP(DBD) in footprinting analyses. A cooperative binding of PhoP(DBD) molecules initiated at conserved core DRus appears to be the mechanism involved in binding of several PhoP(DBD) monomers to those complex operators. The information theory-based model that incorporates the positive or negative contribution to the binding of PhoP(DBD) of adjacent sequences has been used to deduce the structure of PHO boxes and the relevance of each DRu.
Sola-Landa
Alberto
A
Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Av. Real, 1, 24006, León, Spain.
Rodríguez-García
Antonio
A
Apel
Alexander Kristian
AK
Martín
Juan F
JF
D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D016384:Consensus Sequence; D018983:DNA Footprinting; D004269:DNA, Bacterial / Q000737:chemistry; D015964:Gene Expression Regulation, Bacterial; D009875:Operator Regions, Genetic; D010710:Phosphates / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D048372:Streptomyces coelicolor / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D010710:Phosphates; C061064:PhoP protein, Bacteria