Open Access. Powered by Scholars. Published by Universities.®
Biochemistry, Biophysics, and Structural Biology Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 7 of 7
Full-Text Articles in Biochemistry, Biophysics, and Structural Biology
Modulation Of Rho Termination : Expectation Vs Reality, Kavya Sri Sai Chegireddy
Modulation Of Rho Termination : Expectation Vs Reality, Kavya Sri Sai Chegireddy
Legacy Theses & Dissertations (2009 - 2024)
Transcription termination factor Rho is an essential protein in many bacteria. Rho is an ATP-dependent RNA helicase that accounts for 20-50% of termination events in Escherichia coli and plays an important role in preventing pervasive transcription that otherwise might be lethal to bacteria. Rho termination usually occurs in the 3’ UTRs and non-coding regions of the DNA, and the actively transcribing RNA is believed to be protected by translating ribosomes from Rho termination since both transcription and translation are a simultaneous process in prokaryotes. However, in reality, Rho terminates transcription of some protein-coding genes, and fails to terminate transcription of …
Premature Rho-Dependent Transcription Termination In Escherichia Coli : Link To Translation And Gene Regulation, Gabriele Baniulyte
Premature Rho-Dependent Transcription Termination In Escherichia Coli : Link To Translation And Gene Regulation, Gabriele Baniulyte
Legacy Theses & Dissertations (2009 - 2024)
Transcription termination factor Rho is an essential protein in Escherichia coli and related bacteria. The primary function of Rho is to clear unproductive RNA polymerases from the DNA template to minimize negative effects associated with uncontrolled transcription. Although most of the Rho termination events are constitutive, premature Rho-mediated termination was observed at 3% of all affected transcripts indicating active regulation of Rho activity. In this work, we investigated the regulatory mechanism behind premature Rho-dependent transcription termination in two unrelated genes: suhB and topAI. We show that in both cases transcription is terminated inside the coding gene as a consequence of …
Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra
Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra
Legacy Theses & Dissertations (2009 - 2024)
Natural RNAs utilize extensive chemical modifications to diversify their structures and functions. Geranylated-2-thiouridine is a special hydrophobic tRNA modification that has been discovered very recently in several bacteria, namely E. coli, E. aerogenes, P. aeruginosa and S. typhimurium by Liu group. It has been found as a post-transcription modification on the wobble position of anticodon of tRNAs specific for glutamic acid, glutamine and lysine. Geranylated-tRNA was shown to correct the frameshifting during the translation of E. coli. However, the reason of the existing of the modification is still largely unclear. To understand why nature incorporates such a hydrophobic group in …
Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy
Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy
Legacy Theses & Dissertations (2009 - 2024)
DksA is a bacterial gene regulator that functions synergistically with the stress alarmone ppGpp to mediate the stringent response. DksA also functions independently of ppGpp to regulate transcription of a number of genes. DksA function is dependent on its binding affinity to RNA polymerase and requires specific interactions between RNAP and catalytic amino acids located on the coiled coil tip, D74 and A76. While much of the previous work on DksA has focused on understanding the mechanisms of action and the numerous gene targets for transcriptional regulation, little is known about the mechanisms by which DksA expression and function may …
Transcriptional Regulation Of Dksa In E. Coli, Daniel Thomas Woods
Transcriptional Regulation Of Dksa In E. Coli, Daniel Thomas Woods
Legacy Theses & Dissertations (2009 - 2024)
DksA is a global transcription factor that binds RNAP directly to regulate the expression of many genes and operons, including ribosomal RNA, in a ppGpp-dependent or ppGpp–independent manner. It is also involved in facilitating the process of DNA replication by removing stalled transcription elongation complexes that could block the progress of the replication fork. In addition, DksA is important for colonization, establishment of biofilms, and pathogenesis. In order to sustain these various functions, an adequate level of cellular DksA is required. This work tested the hypothesis that the E. coli dksA is substantially regulated at the level of transcription. Using …
Genome-Scale Analyses Of Transcription And Transcriptional Regulation In Bacteria, Devon Marie Fitzgerald
Genome-Scale Analyses Of Transcription And Transcriptional Regulation In Bacteria, Devon Marie Fitzgerald
Legacy Theses & Dissertations (2009 - 2024)
The textbook model of bacterial transcription regulation posits that promoters occur immediately upstream of genes and that transcription factors (TFs) modulate transcription through promoter-proximal binding. However, the recent application of unbiased genome-wide approaches, such as ChIP-seq and RNA-seq, has revealed a much more complex picture, including TF binding and transcription initiation occurring in unexpected locations. This dissertation describes the use of deep sequencing-based approaches to evaluate the genome-wide binding of transcription-related proteins and identify locations of transcription initiation. I have assessed the genome-wide binding of three Escherichia coli TFs and an alternative σ factor. Additionally, I have analyzed genome-wide patterns …
Group Ii Intron Dynamics In Heterologous Hosts, Venkata Raghavendra Aditya Chalamcharla
Group Ii Intron Dynamics In Heterologous Hosts, Venkata Raghavendra Aditya Chalamcharla
Legacy Theses & Dissertations (2009 - 2024)
Group II introns are ribozymes with an innate ability to self-splice. They are found predominantly in bacterial and bacterial-derived organellar genomes, but not in the nuclear genomes of eukaryotes. In bacteria, group II introns often behave as mobile retroelements, invading host DNA and exploiting its machinery to complete the retromobility process. The object of my studies is the group II intron found in the Lactococcus lactis relaxase gene. To determine the nature of the group II intron-host relationship, we performed a genetic screen and identified several host factors that affect group II intron retromobility in Escherichia coli, which provides a …