A DnaA-dependent riboswitch for transcription attenuation of the operon.

Transcription attenuation in response to the availability of a specific amino acid is believed to be controlled by alternative configurations of RNA secondary structures that lead to the arrest of translation or the release of the arrested ribosome from the leader mRNA molecule. In this study, we first report a possible example of the DnaA-dependent riboswitch for transcription attenuation in . We show that (i) DnaA regulates the transcription of the structural genes but not that of the leader gene; (ii) DnaA might bind to rDnaA boxes present in the HisL-SL RNA, and subsequently attenuate the transcription of the operon; (iii) the HisL-SL RNA and rDnaA boxes are phylogenetically conserved and evolutionarily important; and (iv) the translating ribosome is required for deattenuation of the operon, whereas tRNA strengthens attenuation.

Lysophosphatidic Acid-Induced EGFR Transactivation Promotes Gastric Cancer Cell DNA Replication by Stabilizing Geminin in the S Phase.

Geminin, an inhibitor of the DNA replication licensing factor, chromatin licensing and DNA replication factor (Cdt) 1, is essential for the maintenance of genomic integrity. As a multifunctional protein, geminin is also involved in tumor progression, but the molecular details are largely unknown. Here, we found that lysophosphatidic acid (LPA)-induced upregulation of geminin was specific to gastric cancer cells.

YfiF, an unknown protein, affects initiation timing of chromosome replication in Escherichia coli.

The Escherichia coli YfiF protein is functionally unknown, being predicted as a transfer RNA/ribosomal RNA (tRNA/rRNA) methyltransferase. We find that absence of the yfiF gene delays initiation of chromosome replication and the delay is reversed by ectopic expression of YfiF, whereas excess YfiF causes an early initiation. A slight decrease in both cell size and number of origin per mass is observed in ΔyfiF cells.

At the deep end: COVID-19 experiences of Zimbabwean health and care workers in the United Kingdom.

Background And Objectives: Black, Asian and Minority Ethnic groups (BAME) in the UK were disproportionately affected by the first phase of COVID-19 in terms of exposure, negative health and socio-economic impacts and consequences including recorded deaths. However, aggregate categories like BAME mask internal diversities and differences and limit the scope for understanding why disproportionalities occur and appropriate interventions. This paper responds to calls for disaggregated and in-depth participatory community based research to improve culturally nuanced understanding of health inequalities and COVID-19 impacts.

DnaA and LexA Proteins Regulate Transcription of the Gene in : The Role of DnaA in the Control of the SOS Regulon.

The gene belongs to the SOS network, encoding a key component of the nucleotide excision repair. The promoter region contains three identified promoters with four LexA binding sites, one consensus and six potential DnaA binding sites. A more than threefold increase in transcription of the chromosomal gene is observed in both the Δ Δ cells and cells, and a fivefold increase in the Δ Δ cells relative to the wild-type cells.