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Results reveal that the transcriptional regulation of protein kinase Calpha in Glioblastoma multiforme cell lines is dependent on the transcription activator factor, AP-2, which is involved in the phorbol ester-sensitive signaling pathway. Data indicate that an autoregulatory mode of trancription is operating suggesting that the enzyme may be upregulated in Glioblastoma multiforme cell lines.

Research shows that the non-histone chromatin-associated protein encoding Hmga2 promoter region mediates transcription activity. Data further indicate that the polypyrimidine tract binding protein binds to both polypyrimidinic strand of Hmga2 promoter and to ppyr-containing sequences of mouse and human promoters.

Research describes an assay methodology, the multiple promoter comparison assay, which can be used as a general in vitro transcription system for the analysis of the RNA polymerase II genes including multiple start site TATA-less promoters.

The mechanisms that regulate lipopolysaccharide (LPS)-mediated induction of the serum amyloid A (SAA) gene in THP-1 monocyte/macrophage cells were characterized via DNA-binding electromobility shift assay. Analysis of THP-1 monocyte/macrophage cells expressing SAA genes indicated the role of LPS in increasing the levels of SAA messenger RNA and inducing the DNA binding activity of the protein. Furthermore, LPS-mediated SAA gene induction in the monocyte/macrophage cells was regulated by the SAS element within the -280 and -226 bases.

The capacity of the murine c-Ki-ras promoter sequence located in the 29-bp homopurine.homopyridine motif to function as a target for triplex forming oligonucleotides (TFOs) was analyzed by in vitro and in vivo experiments. The transcription activity of the critical c-Ki-ras promoter 29-bp R.Y sequence was inhibited by the TOFs. Furthermore, the inhibition of the transcriptional activity of the 29-bp R.Y sequence indicates that the region can serve as a target for G-rich oligonucleotides that form triplex complexes with A.AT and G.GC triads.

Screening a placental genomic library enables the isolation of a genomic clone containing the intron-exon sequences and the promoter-regulatory region at the E1-beta gene of human pyruvate dehydrogenase complex. Sequence analysis reveals the absence of TATA box homology in the E1-beta promoter and that the promoter has two initiator sequences and three Sp1 sites. The promoter region has seven regions of protein binding and nuclease protection, as revealed by DNase I footprinting analysis. Presence of an orientation-dependent cis element influences the expression of chloroamphenicol acetyltransferase (CAT) activity.

A new method based on the amplification mechanism of RNA Z helps rapid in vitro evolution of bacteriophage RNA polymerase promoters. Replication leads to the preparation of synthetic DNA oligonucleotides with degenerate or completely random sequence. Reverse transcriptase treatment converts the randomized promoter sequence into a double-stranded element. Addition of either T3, T7 or SP6 RNAP leads to the amplification and enrichment of molecules encoding promoter sequences capable of initiating transcription.

Site-directed mutagenesis and transient transfection scheme of expression help locate and analyze binding sites of the protein associated with liver-specific expression of the rat CYP2C13 gene promoter. DNaseI foot printing analysis shows that HNF-1, HNF-3 and members of the orphan receptor subfamily are essential for transactivation of the 2C13 promoter. Positive regulatory elements at the adjacent region of 2C13 promoter located 3' from nucleotide-117 interact with various liver-enriched factors. Interaction of EAR-3 and COUP-TF, but not of HNF-4, with HNF-1 and HNF-3 activates the transcription of 2C13, indicating the importance of intracellular balance between HNF-4 and EAR-3 in gene transcription.

Study of the cDNA and genomic clones encoding a rodent pregnancy-specific glycoprotein (PSG), rnGCM3, reveals that rnCGM3 has two promoter regions PI and PII and the upstream promoter PI has two activator sites, PISI and PISII, for rnCGM3 expression. rnCGM3 has a 5' flanking region and L1 domains identical to that of rnCGM6 and exhibits amino acid sequence homology with rnCGM1 sequences. The PISII motif that regulates the functions of placental cells is found in many trophoblastic genes, indicating its significance in the control of rat PSG genes.

The proximal rat osteocalcin (OC) promoter reveals a TATA element. A powerfully insulated glucocorticoid receptor (GR) binding site is established downstream of the TATA element. The human OC promoter reveals characteristics which vary from that of the rat OC. A region analogous to the human OC promoter reveals a TATA box region with decreased insulation. The TFIID positive transcription factor reveals a binding metabolism with is hindered by GR. This hindering helps the glucocorticoids in negative mediation. The two glucocorticoids display differences OC expression control, due to the presence of the powerful and isolated GR binding element downstream of the TATA in the rat promoter.

Results reveal that the effect of DNA supercoiling on transcription and regulaion depends on the promoter and the regulator activity and that the optimal superhelical density requirement for transcription and regulation vary from promoter to promoter. Data point out to the role played by DNA supercoiling in fine-tuning promoter activities.

The promoter specific effects on cooperativity is not due to a direct coupling between cytidine binding to Escherichia coli cytidine repressor protein and its association with cAMP receptor protein but due to the cytidine binding induced conformational rigidity of the cytidine repressor protein toleranting the geometry of operator sites of different promoters.

Results indicate that the partition of early transcription complexes (ITCs) into productive and unproductive ITCs probably occurs during the formation of open promoter complexes. Data show that the degree of partitioning depends on the individual promoter sequences and initiating nucleotide.

Results reveal that the human transcription factor TFIIB's cterFCP-binding site is similar to that of herpes simplex virus transcriptional activator protein VP16. The cterFCP-binding site in both RAP74 and TFIIBc contain abundant hydrophobic and positively charged amino acids.