scholarly journals Cell-specific nuclear import of plasmid DNA in smooth muscle requires tissue-specific transcription factors and DNA sequences

Gene Therapy ◽  
2008 ◽  
Vol 15 (15) ◽  
pp. 1107-1115 ◽  
Author(s):  
A M Miller ◽  
D A Dean
1999 ◽  
Vol 10 (1) ◽  
pp. 40-57 ◽  
Author(s):  
R.T. Franceschi

Bone formation is a carefully controlled developmental process involving morphogen-mediated patterning signals that define areas of initial mesenchyme condensation followed by induction of cell-specific differentiation programs to produce chondrocytes and osteoblasts. Positional information is conveyed via gradients of molecules, such as Sonic Hedgehog that are released from cells within a particular morphogenic field together with region-specific patterns of hox gene expression. These, in turn, regulate the localized production of bone morphogenetic proteins and related molecules which initiate chondrocyte- and osteoblast-specific differentiation programs. Differentiation requires the initial commitment of mesenchymal stem cells to a given lineage, followed by induction of tissue-specific patterns of gene expression. Considerable information about the control of osteoblast-specific gene expression has come from analysis of the promoter regions of genes encoding proteins like osteocalcin that are selectively expressed in bone. Both general and tissue-specific transcription factors control this promoter. Osf2/Cbfal, the first osteoblast-specific transcription factor to be identified, is expressed early in the osteoblast lineage and interacts with specific DNA sequences in the osteocalcin promoter essential for its selective expression in osteoblasts. The OSF2/CBFA1 gene is necessary for the development of mineralized tissues, and its mutation causes the human disease, cleidocranial dysplasia. Committed osteoprogenitor cells already expressing Osf2/Cbfa1 must synthesize a collagenous ECM before they will differentiate. A ceII:ECM interaction mediated by integrin-type cell-surface receptors is essential for the induction of osteocalcin and other osteoblast-related proteins. This interaction stimulates the binding of Osf2/Cbfa 1 to the osteocalcin promoter through an as-yet-undefined mechanism.


2016 ◽  
Author(s):  
Sheila S. Teves ◽  
Luye An ◽  
Anders S. Hansen ◽  
Liangqi Xie ◽  
Xavier Darzacq ◽  
...  

SummaryDuring mitosis, transcription is shut off, chromatin condenses, and most transcription factors (TFs) are reported to be excluded from chromosomes. How do daughter cells re-establish the original transcription program? Recent discoveries that a select set of TFs remain bound on mitotic chromosomes suggest a potential mechanism for maintaining transcriptional programs through the cell cycle termed mitotic bookmarking. Here we report instead that many TFs remain associated with chromosomes, and that the exclusion previously described is largely a fixation artifact. In particular, most TFs we tested are significantly enriched on mitotic chromosomes. Studies with Sox2 reveal that this mitotic interaction is more dynamic than in interphase and requires both DNA binding and nuclear import. Furthermore, this dynamic mode results from lack of transcriptional activation rather than decreased accessibility of underlying DNA sequences in mitosis. The nature of the cross-linking artifact prompts careful re-examination of the role of TFs in mitotic bookmarking.HighlightsMany transcription factors bind to mitotic chromosomesSox2 mitotic interaction is dynamic and requires DNA binding and nuclear importDNA remains highly accessible in mitotic chromosomesFormaldehyde-based cross-linking leads to mis-localization of TFs


eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Sheila S Teves ◽  
Luye An ◽  
Anders S Hansen ◽  
Liangqi Xie ◽  
Xavier Darzacq ◽  
...  

During mitosis, transcription is shut off, chromatin condenses, and most transcription factors (TFs) are reported to be excluded from chromosomes. How do daughter cells re-establish the original transcription program? Recent discoveries that a select set of TFs remain bound on mitotic chromosomes suggest a potential mechanism for maintaining transcriptional programs through the cell cycle termed mitotic bookmarking. Here we report instead that many TFs remain associated with chromosomes in mouse embryonic stem cells, and that the exclusion previously described is largely a fixation artifact. In particular, most TFs we tested are significantly enriched on mitotic chromosomes. Studies with Sox2 reveal that this mitotic interaction is more dynamic than in interphase and is facilitated by both DNA binding and nuclear import. Furthermore, this dynamic mode results from lack of transcriptional activation rather than decreased accessibility of underlying DNA sequences in mitosis. The nature of the cross-linking artifact prompts careful re-examination of the role of TFs in mitotic bookmarking.


2022 ◽  
Author(s):  
Shashank Kumar Maurya ◽  
Rajnikant Mishra

Abstract Many transcription factors play important roles to maintain the microenvironment, integrity of the blood-brain barrier, the neurons-glia interaction, activities of microglia, composition of cerebrospinal fluid, metabolic activities, concentration of neurotransmitters, presence of inflammatory and anti-inflammatory cytokines, ischemia, stress, aging, neurological disorders, and diseases. The Paired box transcription factors and multifunctional proteins, Pax6 and Pax5 are expressed in brain. They regulate several regulators from cell cycle to cell death. The Pax5, a B-cell lineage-specific activator protein (BSAP), is expressed in the cerebellum, cerebral cortex, hippocampus, olfactory bulb, third ventricles, and choroid plexus. The Pax5 has been observed down-regulated in autism, mental retardation, and Glioblastoma multiforme. The Pax6 affects genes of neurodegeneration, immunological surveillance, and energy homeostasis in brain of mice. The Pax5 and Pax6 recognize several similar DNA sequences and regulate the expression of genes in a tissue-specific manner. Therefore, it is presumed that Pax5 and Pax6, are compartmentalized in brain of mice. Results indicate interactions, cell and tissue-specific compartmentalization, and co-localization of Pax5 and Pax6 in the cerebral cortex, cerebellum, and hippocampus in brain of mice.


2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Corina Samoila ◽  
Alfa Xenia Lupea ◽  
Andrei Anghel ◽  
Marilena Motoc ◽  
Gabriela Otiman ◽  
...  

Denaturing High Performance Liquid Chromatography (DHPLC) is a relatively new method used for screening DNA sequences, characterized by high capacity to detect mutations/polymorphisms. This study is focused on the Transgenomic WAVETM DNA Fragment Analysis (based on DHPLC separation method) of a 485 bp fragment from human EC-SOD gene promoter in order to detect single nucleotide polymorphism (SNPs) associated with atherosclerosis and risk factors of cardiovascular disease. The fragment of interest was amplified by PCR reaction and analyzed by DHPLC in 100 healthy subjects and 70 patients characterized by atheroma. No different melting profiles were detected for the analyzed DNA samples. A combination of computational methods was used to predict putative transcription factors in the fragment of interest. Several putative transcription factors binding sites from the Ets-1 oncogene family: ETS member Elk-1, polyomavirus enhancer activator-3 (PEA3), protein C-Ets-1 (Ets-1), GABP: GA binding protein (GABP), Spi-1 and Spi-B/PU.1 related transcription factors, from the Krueppel-like family: Gut-enriched Krueppel-like factor (GKLF), Erythroid Krueppel-like factor (EKLF), Basic Krueppel-like factor (BKLF), GC box and myeloid zinc finger protein MZF-1 were identified in the evolutionary conserved regions. The bioinformatics results need to be investigated further in others studies by experimental approaches.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Francisco Macías ◽  
Raquel Afonso-Lehmann ◽  
Patricia E. Carreira ◽  
M. Carmen Thomas

Abstract Background Trypanosomatid genomes are colonized by active and inactive mobile DNA elements, such as LINE, SINE-like, SIDER and DIRE retrotransposons. These elements all share a 77-nucleotide-long sequence at their 5′ ends, known as Pr77, which activates transcription, thereby generating abundant unspliced and translatable transcripts. However, transcription factors that mediates this process have still not been reported. Methods TATA-binding protein (TBP) and small nuclear RNA-activating protein 50 kDa (SNAP50) recombinant proteins and specific antibodies raised against them were generated. Protein capture assay, electrophoretic mobility-shift assays (EMSA) and EMSA competition assays carried out using these proteins and nuclear proteins of the parasite together to specific DNA sequences used as probes allowed detecting direct interaction of these transcription factors to Pr77 sequence. Results This study identified TBP and SNAP50 as part of the DNA-protein complex formed by the Pr77 promoter sequence and nuclear proteins of Trypanosoma cruzi. TBP establishes direct and specific contact with the Pr77 sequence, where the DPE and DPE downstream regions are docking sites with preferential binding. TBP binds cooperatively (Hill coefficient = 1.67) to Pr77 and to both strands of the Pr77 sequence, while the conformation of this highly structured sequence is not involved in TBP binding. Direct binding of SNAP50 to the Pr77 sequence is weak and may be mediated by protein–protein interactions through other trypanosomatid nuclear proteins. Conclusions Identification of the transcription factors that mediate Pr77 transcription may help to elucidate how these retrotransposons are mobilized within the trypanosomatid genomes and their roles in gene regulation processes in this human parasite. Graphic abstract


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