We characterized the activity of a human hsp7O gene promoter by in vitro transcription. Analysis of 5' deletion and substitution mutants in HeLa nuclear extracts showed that the basal activity of the promoter depends primarily on a CCAAT-box sequence located at -65. A protein factor, CCAAT-box-binding transcription factor (CTF), was isolated from HeLa nuclear extracts and shown to be responsible for stimulation of transcription in a reconstituted in vitro system. DNase I footprinting revealed that CTF interacts with two CCAAT-box elements located at -65 and -147 of the human hsp7O promoter. An additional binding activity, heat shock transcription factor (HSTF), which interacted with the heat shock element, was also identified in HeLa extract fractions. This demonstrates that the promoter of this human hsp7O gene interacts with at least two positive transcriptional activators, CTF, which is required for CCAAT-box-dependent transcription as in other promoters such as those of globin and herpes simplex virus thymidine kinase genes, and HSTF, which is involved in heat inducibility.Promoters recognized by RNA polymerase II require cis-acting regulatory elements both for constitutive activity and for modulation of transcription by various regulatory processes characteristic of different genes. These elements include sequences near the start of transcription, such as the TATA box, various upstream sequences in the region from approximately -50 to -200, and enhancer sequences that may be located at much greater distances either 5' or 3' to the start site. The mechanisms by which these elements act to control gene expression at the level of transcription are of great interest. One valuable approach to this problem is the identification and purification of sequence-specific DNAbinding proteins that interact with promoter and enhancer elements (9, 25).One regulatory system that has attracted attention is heat shock induction (23). The response of organisms to abnormally high temperature or to a variety of other metabolic stresses involves a rapid and dramatic increase in the rate of transcription initiation of several specific genes encoding heat shock proteins. Control also occurs at the level of mRNA splicing and translation in some, but not all, instances. This heat shock or stress response is very general, and perhaps universal, among eucaryotic organisms. Some of the heat shock gene products, such as the 70-kilodalton family, show remarkable amino acid sequence conservation (23). Perhaps more surprisingly, a 14-base-pair (bp) DNA sequence element, originally identified upstream of several Drosophila heat shock genes, also occurs with a high degree of homology in organisms as distantly related as yeasts and humans (23,28). In addition, the Drosophila hsp70 gene promoter is functional and responsive to heat shock induction in mammalian cells (28,29).

We have examined the promoter sequence requirements for Ela transactivation of the human HSP70 gene by using a transient cotransfection assay. A 5' deletion study has defined a basal transcription unit extending to -74 relative to the transcription initiation site which was fully Ela responsive. Further deletion, abolishing a CCAAT element at -67, drastically reduced basal and Ela-induced expression. A linker-scanner analysis has identified four functional elements within the basal transcription unit which may interact with CTF, SPI, TFIID, and an ATF/APl-like factor. Sequences between -100 and -188 can partially compensate for mutations in these elements. No mutation specifically abolished Ela inducibility. Any reduction in absolute Ela-induced levels was accompanied by a corresponding reduction in absolute basal levels, thereby maintaining a constant relative fold induction. We conclude that Ela transactivation of the human HSP70 promoter does not require any single basal transcription element. We also examined an HSP70 promoter fragment, containing the CCAAT element at -67 and the purine-rich element at -54, out of its normal context by fusing it upstream of a transcriptionally inactive herpes simplex virus thymidine kinase deletion construct containing only the TATA box. The resulting chimeric promoter was fully Ela responsive. Mutagenesis of this promoter fusion demonstrated that the CCAAT element was essential for detectable basal and Ela-induced expression.Mutations in the purine-rich element resulted in an rendered the promoter nonresponsive to Ela.An important point at which gene expression is controlled is transcriptional initiation. The regulation of this step is mediated by DNA binding tr-ans-acting factors that select the site and modulate the rate of specific initiation (for reviews, see references 20 and 41). General transcription factors, such as TFIID, direct RNA polymerase II to the specific start site. The same types of general factors are probably required for specific initiation from most protein-coding genes. Promoter-specific factors bind to transcription elements that regulate the frequency of RNA chain initiation. One class of transcription elements, called upstream elements, is characterized by short sequences of approximately 10 base pairs (bp) that are usually located up to about 110 bp upstream from the RNA start site. These elements modulate transcription in a distance-dependent manner. The other class of transcription elements is enhancers, which are capable of modulating transcription independent of both orientation and distance. Regulation of promoter activity depends on both the number and the type of transcription elements present. The combinatorial organization of elements allows for many complex regulatory patterns with only a small number of transcription factors.Superimposed on the regulation conferred by protein-DNA interactions are the effects of transcription factors which do not bind to DNA. A well-studied example is the 289-amino-acid adenovirus Ela protein, which has ...

A total of 388 men undergoing transurethral resection of the prostate for benign prostatic hypertrophy during 1988 entered a prospective cohort study designed to examine the outcome of surgery during postoperative year 1. Self-administered questionnaires were completed preoperatively, and at 3, 6 and 12 months postoperatively. The surgeons completed 1 questionnaire shortly after surgery and another questionnaire 3, 6 or 12 months later. The mortality rate during the 12 months of followup was 2.8% (11 deaths). The surgeons reported perioperative complications in 14% of the patients and immediate postoperative complications, excluding urinary tract infections, in 17%. During the first 3 months postoperatively 38% of the patients reported incontinence and 25% had a urinary tract infection. Between 6 and 12 months postoperatively only 12% of the patients were troubled by either condition. The postoperative prevalence of impotence (24%) did not alter during followup and was similar to that reported preoperatively (22%). Of the patients 74% reported feeling better and 78% experienced a decrease in the overall level of symptoms postoperatively. The improvement in symptom levels was greatest in those with the most severe preoperative symptoms, and obstructive symptoms were alleviated slightly more than irritative symptoms.