Contacts in context: promoter specificity and macromolecular interactions in transcription

Article Abstract:

Transcriptional regulation in eukaryotes is a finely-tuned process that is controlled by the molecular machinery that directs mRNA synthesis. Over 40 different protein sub-units are believed to work in concert to regulate the transcription of protein-encoding genes by RNA polymerase II. These transcription factors direct the activity of genes in very specific ways. Among others, it has been discovered that RNA polymerase II transcription is deeply influenced by promoter-specific recognition in chromosomes as this process aids the mechanisms that guide the initiation of transcription.

Gene expression, Promoters (Genetics)

Transcript cleavage factors from E. coli

Article Abstract:

A new transcript cleavage factor named GreB was identified in Escherichia coli and characterized, along with another previously identified factor, GreA. The results showed that both factors could induce cleavage at the 3' terminal end of the nascent strand, resulting in the release of the 3' proximal fragment and subsequent elongation at the new 3' end. The factors differed in the length of the released 3' proximal fragment, as well as in the cleavage mechanism. Based on the cleavage and elongation arrest observations, a model for ternary complex rearrangement is presented.

Genetic aspects, Escherichia coli, RNA splicing

FACT, a factor that facilitates transcript elongation through nucleosomes

Article Abstract:

Research was conducted to investigate transcriptional activation requirements by RNA polymerase II (RNAP II) using chromatic templates. A factor that facilitated chromatic transcription was purified while an S-190 assembly extract was characterized from Drosophila embryos. Results indicated that RNAP II elongation factors can be divided into two classes and that the productive transcription on chromatin templates were correlated with the action of factors from RNAP II and its general transcription factors.

Chromatin