Saturation mutagenesis of an Escherichia coli rRNA promoter and initial characterization of promoter variants

Allosteric control of Escherichia coli rRNA promoter complexes by DksA.

The Escherichia coli DksA protein inserts into the RNA polymerase (RNAP) secondary channel, modifying the transcription initiation complex so that promoters with specific kinetic characteristics are regulated by changes in the concentrations of ppGpp and NTPs. We used footprinting assays to determine the specific kinetic intermediate, RP(I), on which DksA acts. Genetic approaches identified sub...

Antitermination of transcription from an Escherichia coli ribosomal RNA promoter.

The Escherichia coli lac and ara promoters and rrnC ribosomal RNA promoter-leader region were fused to lacZYA. Transcription termination signals were introduced into the lac genes of these fusions by Tn9 and IS1 insertions. Measurement of lac enzymes from upstream and downstream of the insertions showed that termination signals resulting from these insertions are very efficient when transcripti...

expression of reteplase in escherichia coli top10 using arabinose promoter

Construction and initial characterization of Escherichia coli strains with few or no intact chromosomal rRNA operons.

The Escherichia coli genome carries seven rRNA (rrn) operons, each containing three rRNA genes. The presence of multiple operons has been an obstacle to many studies of rRNA because the effect of mutations in one operon is diluted by the six remaining wild-type copies. To create a tool useful for manipulating rRNA, we sequentially inactivated from one to all seven of these operons with deletion...

the study of aaag repeat polymorphism in promoter of errg gene and its association with the risk of breast cancer in isfahan region

چکیده: سرطان پستان دومین عامل مرگ مرتبط با سرطان در خانم ها است. از آنجا که سرطان پستان یک تومور وابسته به هورمون است، می تواند توسط وضعیت هورمون های استروئیدی شامل استروژن و پروژسترون تنظیم شود. استروژن نقش مهمی در توسعه و پیشرفت سرطان پستان ایفا می کند و تاثیر خود را روی بیان ژن های هدف از طریق گیرنده های استروژن اعمال می کند. اما گروه دیگری از گیرنده های هسته ای به نام گیرنده های مرتبط به ا...