The synthesis of nascent RNA is a discontinuous process in which phases of productive elongation by RNA polymerase are interrupted by frequent pauses. Transcriptional pausing was first observed decades ago, but was long considered to be a special feature of transcription at certain genes. This view was challenged when studies using genome-wide approaches revealed that RNA polymerase II pauses a...

A nationwide surveillance for antimicrobial susceptibility in Escherichia coli strains isolated from food-producing animals in Japan was conducted from 1999 to 2002. Eighteen cefazolin-resistant E. coli strains were isolated from broilers. Six were CTX-M-type producing, and eight were CMY-2 producing, while eight had mutations at the ampC promoter region.

Chemical exposures are in principle preventable causes of cancer. People are exposed to chemicals already during fetal period and the possibility of disturbances in human development by chemical compounds leading to cancer later in life has been proven by diethylstilbestrol. The mechanisms most probably include epigenetic modifications of promoter regions of key genes. The world-wide increases ...

â  hepadnaviruses employ an unusual strategy for the production of enormous number of virions during replication which makes rapid and substantial genetic sequence changes and alterations. the pathogenesis and clearance of hepatitis b virus (hbv) infection are engaged by the selection and expression of viral mutants durâ­ing virus-host interactions. mutations in regulatory regions such as the b...

The carboxyl-terminal domain (CTD) of RNA polymerase II (Pol II) can be phosphorylated at serine 2 (Ser-2) and serine 5 (Ser-5) of the CTD heptad repeat YSPTSPS, and this phosphorylation is important in coupling transcription to RNA processing, including 5' capping, splicing, and polyadenylation. The mammalian endogenous dihydrofolate reductase and gamma-actin genes have been used to study the ...

MOTIVATION To develop an algorithm utilizing differential hexamer frequency analysis to discriminate promoter from non-promoter regions in vertebrate DNA sequence, without relying upon an extensive database of known transcriptional elements. RESULTS By determining hexamer frequencies derived from known promoter regions, coding regions and non-coding regions in vertebrates' DNA sequence, and a...

Promoter activity of the Campoletis sonorensis polydnavirus (CsPDV) WHv1.6 gene was analysed by transient transfection assays in insect cell culture using constructs expressing the CAT gene. Deletions of the WHv1.6 gene promoter were used to define promoter regions important for expression. Progressive deletion of the regions upstream of the TATA box reduced the promoter activity, whereas delet...