City managers once were viewed as neutral technicians with limited roles in the policymaking process, but scholars increasingly came to appreciate that, for managers, the separation between politics and administration often was more symbolic than factual.

Homeowners associations (HOAs) are private governments that are reshaping urban governance and service delivery in large parts of the United States. Despite the fact that millions of Americans are HOA members, the fi eld of public aff airs has paid scant attention to these new governance entities. Th e essays in this symposium call attention to HOAs' potential eff ects on urban services and civic life in the hope of sparking interest among scholars and public managers to include HOAs in our understanding, research, and teaching of contemporary urban governance.

In this article, we examine homeowners associations (HOAs) as private providers of what are traditionally considered local government services: streets, security, recreation, maintenance, and public works (e.g., water, drainage, sewerage, and trash collection). Although much has been theorized about the nature of such organizations, little empirical data has been collected to examine these prescriptions. We present the results of a 2005 survey of large-scale HOAs to shed light on the characteristics of such associations, and especially the nature of their relationships with local governments that may be providing similar services. We find that the survey raises interesting questions about how these associations interact with local governments, and that the nature of private as opposed to public governance demands further study. Copyright 2006 by The Policy Studies Organization.

We performed two sets of in vitro selections to dissect the role of the ؊10 base sequence in determining the rate and efficiency with which Escherichia coli RNA polymerase-70 forms stable complexes with a promoter. We identified sequences that (i) rapidly form heparin-resistant complexes with RNA polymerase or (ii) form heparin-resistant complexes at very low RNA polymerase concentrations. The sequences selected under the two conditions differ from each other and from the consensus ؊10 sequence. The selected promoters have the expected enhanced binding and kinetic properties and are functionally better than the consensus promoter sequence in directing RNA synthesis in vitro. Detailed analysis of the selected promoter functions shows that each step in this multistep pathway may have different sequence requirements, meaning that the sequence of a strong promoter does not contain the optimal sequence for each step but instead is a compromise sequence that allows all steps to proceed with minimal constraint.Gene expression is often regulated at transcription initiation. In the absence of gene regulatory proteins, the rate of initiation at a particular promoter depends on the concentration of RNA polymerase and the sequence of the promoter element. In both prokaryotes and eukaryotes, transcription initiation is a multistep process that begins with sequencespecific recognition and proceeds through formation of two or more intermediate RNA polymerase-promoter complexes prior to synthesis of the first phosphodiester bond of the product RNA (31). Subsequently, the initiated complex isomerizes into one that generates full-length RNA products (for exceptions, see references 18 and 34). The fractional occupancy of a promoter by RNA polymerase and the rate at which RNA polymerase proceeds through the initiation pathway determine, in part, the amount of RNA produced from a gene.The pathway for transcription initiation is best understood in prokaryotes (Fig. 1A). In these organisms, RNA polymerase binds to promoter DNA and initially forms an unstable "closed" complex that dissociates with the addition of polyanionic competitors such as single-stranded DNA or heparin (31). The closed complex isomerizes through a number of intermediate complexes (21,33) in which the DNA at the transcription start site remains base paired (Fig. 1A). Subsequently, these intermediates isomerize to form one or more competitor-resistant "open" complexes, in which the DNA strands surrounding the transcription start site display increasing separation (4, 36). RNA polymerase initiation complexes form after the DNA in the region between Ϫ11 and ca. ϩ5 is fully denatured and the synthesis of small (8-to 12-base) "abortive" oligonucleotide products takes place and/or the polymerase escapes from the promoter, forming an elongation complex competent to synthesize full-length RNA transcripts.In prokaryotes, both the affinity of RNA polymerase for DNA and the rate of isomerization of the RNA polymerase-DNA complexes to form the various intermediate species dep...

Expression of the Bacillus subtilis trp genes is negatively regulated by an 11-subunit trp RNA-binding attenuation protein (TRAP), which is activated to bind RNA by binding L-tryptophan. We used Western blotting to estimate that there are 200 to 400 TRAP 11-mer molecules per cell in cells grown in either minimal or rich medium.In Bacillus subtilis and several related bacilli, expression of genes involved in tryptophan metabolism is regulated in response to changes in intracellular L-tryptophan levels by an RNA-binding protein called TRAP (trp RNA-binding attenuation protein) (4,5,12,13). TRAP regulates transcription of the trpEDCFBA operon through an attenuation mechanism (6, 18), as well as translation of trpE by altering the trp mRNA structure to sequester the trpE Shine-Dalgarno sequence in a stem-loop (10,18,21). TRAP also regulates translation of trpG (pabA) (11, 30), trpP (yhaG) (23, 29), and ycbK (24) through direct competition with ribosomes for binding to these mRNAs. In addition, the activity of TRAP is regulated by the anti-TRAP (AT) protein (26,27). AT binds to tryptophanactivated TRAP and inhibits it from binding to its RNA targets, thereby increasing expression of the trp genes.