Working under the assumption that up- or downregulation of genes implicated in chemoresistance may be the result of altered function of regulatory transcription factors (TF), over-represented TF-binding sites of gene lists previously associated with doxorubicin resistance were the target of our search. First, a data warehouse was set up containing 52 genes which were present in at least two gene lists; of those, proximal promoter sequences (1 kb upstream and 0.05 kb downstream of the transcriptional start sites) could be retrieved from genomic databases for 45 genes using the EZ-Retrieve. The TOUCAN tool MotifScanner, which searches the TRANSFAC database, was used to detect TF-binding sites (TFBSs) in our set of sequences. The statistics tool of the Java program TOUCAN was applied to the data with the appropriate expected frequencies file to compare the measured prevalence to a background model. The most significantly over-represented TFBS was that of E47 (p=0.00024, prevalence: 0.2 vs. background: 8.19E-6). In summary, based on the results of our analysis it is hypothesized that the E47 transcription factor may contribute to doxorubicin resistance.
Download full-text PDF |
Source |
---|
Nat Commun
January 2025
Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
The rate at which transcription factors (TFs) bind their cognate sites has long been assumed to be limited by diffusion, and thus independent of binding site sequence. Here, we systematically test this assumption using cell-to-cell variability in gene expression as a window into the in vivo association and dissociation kinetics of the model transcription factor LacI. Using a stochastic model of the relationship between gene expression variability and binding kinetics, we performed single-cell gene expression measurements to infer association and dissociation rates for a set of 35 different LacI binding sites.
View Article and Find Full Text PDFGene expression is coordinated by a multitude of transcription factors (TFs), whose binding to the genome is directed through multiple interconnected epigenetic signals, including chromatin accessibility and histone modifications. These complex networks have been shown to be disrupted during aging, disease, and cancer. However, profiling these networks across diverse cell types and states has been limited due to the technical constraints of existing methods for mapping DNA:Protein interactions in single cells.
View Article and Find Full Text PDFThe proximity ligation-based Hi-C and derivative methods are the mainstream tools to study genome-wide chromatin interactions. These methods often fragment the genome using enzymes functionally irrelevant to the interactions per se, restraining the efficiency in identifying structural features and the underlying regulatory elements. Here we present Footprint-C, which yields high-resolution chromatin contact maps built upon intact and genuine footprints protected by transcription factor (TF) binding.
View Article and Find Full Text PDFNat Commun
December 2024
Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway.
Short tandem repeats (STRs) have emerged as important and hypermutable sites where genetic variation correlates with gene expression in plant and animal systems. Recently, it has been shown that a broad range of transcription factors (TFs) are affected by STRs near or in the DNA target binding site. Despite this, the distribution of STR motif repetitiveness in eukaryote genomes is still largely unknown.
View Article and Find Full Text PDFMethods Mol Biol
December 2024
Department of Microbiology and Plant Pathology, University of California, Riverside, CA, USA.
Transcriptional regulation allows cells to execute developmental programs, maintain homeostasis, and respond to intra- and extracellular signals. Central to these processes are promoters, which in eukaryotes are sequences upstream of genes that bind transcription factors (TFs) and which recruit RNA polymerase to initiate mRNA synthesis. Valuable tools for studying promoters include reporter genes, which can be used to indicate when and where genes are activated.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!