scholarly journals A variant octamer motif in a Xenopus H2B histone gene promoter is not required for transcription in frog oocytes.

1991 ◽  
Vol 11 (2) ◽  
pp. 641-654 ◽  
Author(s):  
C Hinkley ◽  
M Perry
Keyword(s):  
Cell Cycle ◽  
Transcription Initiation ◽  
Regulatory Element ◽  
Regulatory Elements ◽  
Histone Gene ◽  
Site Directed Mutagenesis ◽  
Regulatory Sequences ◽  
Chromosomal Dna ◽  
Transcriptional Regulatory ◽  
Octamer Motif

Xenopus oocytes, arrested in G2 before the first meiotic division, accumulate histone mRNA and protein in the absence of chromosomal DNA replication and therefore represent an attractive biological system in which to examine histone gene expression uncoupled from the cell cycle. Previous studies have shown that sequences necessary for maximal levels of transcription in oocytes are present within 200 bp at the 5' end of the transcription initiation site for genes encoding each of the five major Xenopus histone classes. We have defined by site-directed mutagenesis individual regulatory sequences and characterized DNA-binding proteins required for histone H2B gene transcription in injected oocytes. The Xenopus H2B gene has a relatively simple promoter containing several transcriptional regulatory elements, including TFIID, CBP, and ATF/CREB binding sites, required for maximal transcription. A sequence (CTTTACAT) in the H2B promoter resembling the conserved octamer motif (ATTTGCAT), the target for cell-cycle regulation of a human H2B gene, is not required for transcription in oocytes. Nonetheless, substitution of a consensus octamer motif for the variant octamer element activates H2B transcription. Oocyte factors, presumably including the ubiquitous Oct-1 factor, specifically bind to the consensus octamer motif but not to the variant sequence. Our results demonstrate that a transcriptional regulatory element involved in lymphoid-specific expression of immunoglobulin genes and in S-phase-specific activation of mammalian H2B histone genes can activate transcription in nondividing amphibian oocytes.

A variant octamer motif in a Xenopus H2B histone gene promoter is not required for transcription in frog oocytes

1991 ◽  
Vol 11 (2) ◽  
pp. 641-654
Author(s):  
C Hinkley ◽  
M Perry
Keyword(s):  
Cell Cycle ◽  
Transcription Initiation ◽  
Regulatory Element ◽  
Regulatory Elements ◽  
Histone Gene ◽  
Site Directed Mutagenesis ◽  
Regulatory Sequences ◽  
Chromosomal Dna ◽  
Transcriptional Regulatory ◽  
Octamer Motif

Xenopus oocytes, arrested in G2 before the first meiotic division, accumulate histone mRNA and protein in the absence of chromosomal DNA replication and therefore represent an attractive biological system in which to examine histone gene expression uncoupled from the cell cycle. Previous studies have shown that sequences necessary for maximal levels of transcription in oocytes are present within 200 bp at the 5' end of the transcription initiation site for genes encoding each of the five major Xenopus histone classes. We have defined by site-directed mutagenesis individual regulatory sequences and characterized DNA-binding proteins required for histone H2B gene transcription in injected oocytes. The Xenopus H2B gene has a relatively simple promoter containing several transcriptional regulatory elements, including TFIID, CBP, and ATF/CREB binding sites, required for maximal transcription. A sequence (CTTTACAT) in the H2B promoter resembling the conserved octamer motif (ATTTGCAT), the target for cell-cycle regulation of a human H2B gene, is not required for transcription in oocytes. Nonetheless, substitution of a consensus octamer motif for the variant octamer element activates H2B transcription. Oocyte factors, presumably including the ubiquitous Oct-1 factor, specifically bind to the consensus octamer motif but not to the variant sequence. Our results demonstrate that a transcriptional regulatory element involved in lymphoid-specific expression of immunoglobulin genes and in S-phase-specific activation of mammalian H2B histone genes can activate transcription in nondividing amphibian oocytes.

Histone H3 transcription in Saccharomyces cerevisiae is controlled by multiple cell cycle activation sites and a constitutive negative regulatory element

1992 ◽  
Vol 12 (12) ◽  
pp. 5455-5463 ◽  
Author(s):  
K B Freeman ◽  
L R Karns ◽  
K A Lutz ◽  
M M Smith
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Cell Division ◽  
Transcriptional Activation ◽  
Regulatory Element ◽  
Histone H3 ◽  
Regulatory Elements ◽  
Cell Division Cycle ◽  
Cell Cycle Activation ◽  
Multiple Cell

The promoters of the Saccharomyces cerevisiae histone H3 and H4 genes were examined for cis-acting DNA sequence elements regulating transcription and cell division cycle control. Deletion and linker disruption mutations identified two classes of regulatory elements: multiple cell cycle activation (CCA) sites and a negative regulatory site (NRS). Duplicate 19-bp CCA sites are present in both the copy I and copy II histone H3-H4 promoters arranged as inverted repeats separated by 45 and 68 bp. The CCA sites are both necessary and sufficient to activate transcription under cell division cycle control. A single CCA site provides cell cycle control but is a weak transcriptional activator, while an inverted repeat comprising two CCA sites provides both strong transcriptional activation and cell division cycle control. The NRS was identified in the copy I histone H3-H4 promoter. Deletion or disruption of the NRS increased the level of the histone H3 promoter activity but did not alter the cell division cycle periodicity of transcription. When the CCA sites were deleted from the histone promoter, the NRS element was unable to confer cell division cycle control on the remaining basal level of transcription. When the NRS element was inserted into the promoter of a foreign reporter gene, transcription was constitutively repressed and did not acquire cell cycle regulation.

Identification of upstream and intragenic regulatory elements that confer cell-type-restricted and differentiation-specific expression on the muscle creatine kinase gene

1988 ◽  
Vol 8 (7) ◽  
pp. 2896-2909 ◽  
Author(s):  
E A Sternberg ◽  
G Spizz ◽  
W M Perry ◽  
D Vizard ◽  
T Weil ◽  
...  
Keyword(s):  
Transcription Initiation ◽  
Regulatory Element ◽  
Simian Virus 40 ◽  
Muscle Cells ◽  
Regulatory Elements ◽  
Initiation Site ◽  
Simian Virus ◽  
Cell Type ◽  
Specific Expression ◽  
Developing Muscle

Terminal differentiation of skeletal myoblasts is accompanied by induction of a series of tissue-specific gene products, which includes the muscle isoenzyme of creatine kinase (MCK). To begin to define the sequences and signals involved in MCK regulation in developing muscle cells, the mouse MCK gene has been isolated. Sequence analysis of 4,147 bases of DNA surrounding the transcription initiation site revealed several interesting structural features, some of which are common to other muscle-specific genes and to cellular and viral enhancers. To test for sequences required for regulated expression, a region upstream of the MCK gene from -4800 to +1 base pairs, relative to the transcription initiation site, was linked to the coding sequences of the bacterial chloramphenicol acetyltransferase (CAT) gene. Introduction of this MCK-CAT fusion gene into C2 muscle cells resulted in high-level expression of CAT activity in differentiated myotubes and no detectable expression in proliferating undifferentiated myoblasts or in nonmyogenic cell lines. Deletion mutagenesis of sequences between -4800 and the transcription start site showed that the region between -1351 and -1050 was sufficient to confer cell type-specific and developmentally regulated expression on the MCK promoter. This upstream regulatory element functioned independently of position, orientation, or distance from the promoter and therefore exhibited the properties of a classical enhancer. This upstream enhancer also was able to confer muscle-specific regulation on the simian virus 40 promoter, although it exhibited a 3- to 5-fold preference for its own promoter. In contrast to the cell type- and differentiation-specific expression of the upstream enhancer, the MCK promoter was able to function in myoblasts and myotubes and in nonmyogenic cell lines when combined with the simian virus 40 enhancer. An additional positive regulatory element was identified within the first intron of the MCK gene. Like the upstream enhancer, this intragenic element functioned independently of position, orientation, and distance with respect to the MCK promoter and was active in differentiated myotubes but not in myoblasts. These results demonstrate that expression of the MCK gene in developing muscle cells is controlled by complex interactions among multiple upstream and intragenic regulatory elements that are functional only in the appropriate cellular context.

scholarly journals Transcription start site analysis reveals widespread divergent transcription in D. melanogaster and core promoter-encoded enhancer activities

2017 ◽  
Author(s):  
Sarah Rennie ◽  
Maria Dalby ◽  
Marta Lloret-Llinares ◽  
Stylianos Bakoulis ◽  
Christian Dalager Vaagensø ◽  
...  
Keyword(s):  
Transcription Initiation ◽  
Core Promoter ◽  
Regulatory Element ◽  
Regulatory Elements ◽  
Chromatin Interaction ◽  
Promoter Strength ◽  
Gene Promoters ◽  
Core Promoters ◽  
Promoter Architecture ◽  
Regulatory Functions

ABSTRACTMammalian gene promoters and enhancers share many properties. They are composed of a unified promoter architecture of divergent transcripton initiation and gene promoters may exhibit enhancer function. However, it is currently unclear how expression strength of a regulatory element relates to its enhancer strength and if the unifying architecture is conserved across Metazoa. Here we investigate the transcription initiation landscape and its associated RNA decay in D. melanogaster. Surprisingly, we find that the majority of active gene-distal enhancers and a considerable fraction of gene promoters are divergently transcribed. We observe quantitative relationships between enhancer potential, expression level and core promoter strength, providing an explanation for indirectly related histone modifications that are reflecting expression levels. Lowly abundant unstable RNAs initiated from weak core promoters are key characteristics of gene-distal developmental enhancers, while the housekeeping enhancer strengths of gene promoters reflect their expression strengths. The different layers of regulation mediated by gene-distal enhancers and gene promoters are also reflected in chromatin interaction data. Our results suggest a unified promoter architecture of many D. melanogaster regulatory elements, that is universal across Metazoa, whose regulatory functions seem to be related to their core promoter elements.

P-element-mediated enhancer detection applied to the study of oogenesis in Drosophila

Development ◽  
1989 ◽  
Vol 107 (2) ◽  
pp. 189-200 ◽  
Author(s):  
U. Grossniklaus ◽  
H.J. Bellen ◽  
C. Wilson ◽  
W.J. Gehring
Keyword(s):  
Germ Line ◽  
Expression Patterns ◽  
Cell Types ◽  
Regulatory Elements ◽  
P Element ◽  
Regulatory Sequences ◽  
Transcriptional Regulatory ◽  
Morphological Criteria ◽  
Enhancer Detection ◽  
New Strategies

We have stained the ovaries of nearly 600 different Drosophila strains carrying single copies of a P-element enhancer detector. This transposon detects neighbouring genomic transcriptional regulatory sequences by means of a beta-galactosidase reporter gene. Numerous strains are stained in specific cells and at specific stages of oogenesis and provide useful ovarian markers for cell types that in some cases have not previously been recognized by morphological criteria. Since recent data have suggested that a substantial number of the regulatory elements detected by enhancer detection control neighbouring genes, we discuss the implications of our results concerning ovarian gene expression patterns in Drosophila. We have also identified a small number of insertion-linked recessive mutants that are sterile or lead to ovarian defects. We observe a strong correlation with specific germ line staining patterns in these strains, suggesting that certain patterns are more likely to be associated with female sterile genes than others. On the basis of our results, we suggest new strategies, which are not primarily based on the generation of mutants, to screen for and isolated female sterile genes.

A Drosophila GATA family member that binds to Adh regulatory sequences is expressed in the developing fat body

Development ◽  
1993 ◽  
Vol 119 (3) ◽  
pp. 623-633 ◽  
Author(s):  
T. Abel ◽  
A.M. Michelson ◽  
T. Maniatis
Keyword(s):  
Fat Body ◽  
Regulatory Elements ◽  
Drosophila Embryo ◽  
Cdna Clones ◽  
Regulatory Sequences ◽  
Mammalian Development ◽  
Sequence Element ◽  
Gata Factors ◽  
Transcriptional Regulatory ◽  
Gata Family

We have identified a Drosophila transcription factor that binds a sequence element found in the larval promoters of all known alcohol dehydrogenase (Adh) genes. DNA sequence analysis of cDNA clones encoding this protein, box A-binding factor (ABF), reveals that it is a member of the GATA family of transcriptional regulatory factors. ABF-binding sites within the D. mulleri and D. melanogaster larval Adh promoters function as positive regulatory elements and in cotransfection experiments, ABF functions as a transcriptional activator. In further support of a role for ABF in the regulation of Adh expression, ABF mRNA is expressed in the embryonic fat body, a tissue that contains high levels of Adh mRNA. Our studies demonstrate that the fat body develops from segmentally repeated clusters of mesodermal cells, which later expand and coalesce to form the mature fat body. These observations establish ABF as the earliest known fat body precursor marker in the Drosophila embryo. Together with the established role of GATA factors during mammalian development, these results suggest that ABF may play a key role in the organogenesis of the fat body.

Accurate Identification of Active Transcriptional Regulatory Elements from Global Run-On and Sequencing Data

2014 ◽  
Author(s):  
Charles G Danko ◽  
Stephanie L Hyland ◽  
Leighton J Core ◽  
Andre L Martins ◽  
Colin T Waters ◽  
...  
Keyword(s):  
Multiple Scales ◽  
Regulatory Element ◽  
Cell Types ◽  
Regulatory Elements ◽  
Support Vector ◽  
Sequencing Data ◽  
Accurate Identification ◽  
Single Experiment ◽  
Transcriptional Regulatory Elements ◽  
Transcriptional Regulatory

Identification of the genomic regions that regulate transcription remains an important open problem. We have recently shown that global run-on and sequencing (GRO-seq) with enrichment for 5′-capped RNAs reveals patterns of divergent transcription that accurately mark active transcriptional regulatory elements (TREs), including enhancers and promoters. Here, we demonstrate that active TREs can be identified with comparable accuracy by applying sensitive machine-learning methods to standard GRO-seq and PRO-seq data, allowing TREs to be assayed together with transcription levels, elongation rates, and other transcriptional features, in a single experiment. Our method, called discriminative Regulatory Element detection from GRO-seq (dREG), summarizes GRO-seq read counts at multiple scales and uses support vector regression to predict active TREs. The predicted TREs are strongly enriched for marks associated with functional elements, including H3K27ac, transcription factor binding sites, eQTLs, and GWAS-associated SNPs. Using dREG, we survey TREs in eight cell types and provide new insights into global patterns of TRE assembly and function.

Aberrant Simultaneous ERK and CDK2 Kinase Activity Discloses Leukemia

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2487-2487
Author(s):  
Gernot Stuhler ◽  
Matthias Krusch ◽  
Stefan Stevanovic ◽  
Stefan Gattenlöhner ◽  
Helmut R. Salih
Keyword(s):  
Cell Cycle ◽  
Signaling Pathways ◽  
Malignant Transformation ◽  
Internal Control ◽  
Conflicts Of Interest ◽  
Cancer Therapeutics ◽  
Regulatory Elements ◽  
Site Directed Mutagenesis ◽  
Bistable Switch ◽  
Cdk2 Activity

Abstract Abstract 2487 Genome wide analyses of regulatory elements have identified successive waves of coherent transcriptional programs guiding through and controlling cell cycle progression. Each of these modules induces its successor and, at the same time, inactivates the key kinases active in the antecedent phase of the cycle. In an initial signaling module, the RAF-MEK-ERK pathway is central for phosphorylation of the tumor suppressor Rb (retinoblastoma), release of transcription factors of the E2F family and subsequent cell cycle entry. CDK2 is the driving force and guardian of the consecutive phase where DNA replication occurs. After having initiated CDK2 activity, ERK is inactive and non-inducible (Pouyssegur 2003). The pRB/CDK2 node thus is a bistable switch that converts mitogenic information into an irreversible cellular commitment to duplicate, and uncouples the cell's growth and division program from environmental or internal control. Comparing primary leukemic blasts with healthy CD34+ hematopoietic progenitor cells, we here show that simultaneous rather than serial activation of the canonical ERK and CDK2 pathways is a recurrent aberrant signaling motif indicative for malignant transformation. This phenomenon was observed in leukemic blasts and also in cancer cells of epithelial and mesenchymal provenience, but not in healthy or regenerating tissues using flow cytometry and confocal microscopy techniques and phospho-epitope specific antibodies. To further visualize this “forbidden ERK/CDK2 signal combination”, we developed a biosensor comprising both, the optimal peptide substrates for ERK and CDK kinases attached to a fluorescein tag and a membrane-penetrating nona-arginine (9R) moiety. This compound enables detection of simultaneous ERK and CDK2 activity on single cell level by means of electrophoretic mobility shift. Site directed mutagenesis of the two phospho sites confirmed mutual exclusive substrate recognition thus ascertaining the specificity of the read out system. In healthy CD34+ cells, single but never dual phosphorylation of the biosensor was detected even after stimulation with PMA/Ionomycin, the latter establishing a non-physiological, proliferative compartment. These findings confirm the serial and mutually exclusive piloting of ERK and CDK2 signaling pathways in non-transformed cells. In stark contrast, dual phosphorylation of the biosensor peptide was observed upon analysis of leukemic blasts. Thus, simultaneous and therefore aberrant recruitment of ERK and Rb/E2F/CDK2 cell cycle elements in transformed but not healthy cells discloses leukemia. Our data do not add to the increasing complexity of genetic insults associated with malignant transformation. Rather, we demonstrate that violations of the orderly recruitment of common signaling pathways are indicative for a malignant phenotype which can be detected on the basis of aberrant spatiotemporal organization of essential cell signaling nodes. Our findings do not only anticipate a novel way to diagnose malignancy. Based on the structural information provided by our template peptide, we further envisage a new class of cancer therapeutics where a nontoxic prodrug is converted into a tumoricidal substance exclusively in malignant cells after simultaneous double-phosphorylation by aberrantly active kinases. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Common core sequences are found in skeletal muscle slow- and fast-fiber-type-specific regulatory elements.

1996 ◽  
Vol 16 (5) ◽  
pp. 2408-2417 ◽  
Author(s):  
M Nakayama ◽  
J Stauffer ◽  
J Cheng ◽  
S Banerjee-Basu ◽  
E Wawrousek ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Spatial Organization ◽  
Molecular Mechanisms ◽  
Fiber Type ◽  
Regulatory Element ◽  
Regulatory Elements ◽  
Upstream Region ◽  
Regulatory Sequences ◽  
Fast Fiber ◽  
Core Elements

The molecular mechanisms generating muscle diversity during development are unknown. The phenotypic properties of slow- and fast-twitch myofibers are determined by the selective transcription of genes coding for contractile proteins and metabolic enzymes in these muscles, properties that fail to develop in cultured muscle. Using transgenic mice, we have identified regulatory elements in the evolutionarily related troponin slow (TnIs) and fast (TnIf) genes that confer specific transcription in either slow or fast muscles. Analysis of serial deletions of the rat TnIs upstream region revealed that sequences between kb -0.95 and -0.5 are necessary to confer slow-fiber-specific transcription; the -0.5-kb fragment containing the basal promoter was inactive in five transgenic mouse lines tested. We identified a 128-bp regulatory element residing at kb -0.8 that, when linked to the -0.5-kb TnIs promoter, specifically confers transcription to slow-twitch muscles. To identify sequences directing fast-fiber-specific transcription, we generated transgenic mice harboring a construct containing the TnIs kb -0.5 promoter fused to a 144-bp enhancer derived from the quail TnIf gene. Mice harboring the TnIf/TnIs chimera construct expressed the transgene in fast but not in slow muscles, indicating that these regulatory elements are sufficient to confer fiber-type-specific transcription. Alignment of rat TnIs and quail TnIf regulatory sequences indicates that there is a conserved spatial organization of core elements, namely, an E box, a CCAC box, a MEF-2-like sequence, and a previously uncharacterized motif. The core elements were shown to bind their cognate factors by electrophoretic mobility shift assays, and their mutation demonstrated that the TnIs CCAC and E boxes are necessary for transgene expression. Our results suggest that the interaction of closely related transcriptional protein-DNA complexes is utilized to specify fiber type diversity.

scholarly journals Segments of the POU domain influence one another's DNA-binding specificity.

1992 ◽  
Vol 12 (2) ◽  
pp. 455-467 ◽  
Author(s):  
R Aurora ◽  
W Herr
Keyword(s):  
Dna Binding ◽  
Sequence Similarity ◽  
Binding Specificity ◽  
Regulatory Elements ◽  
Regulatory Sequences ◽  
Surprising Result ◽  
Pou Domain ◽  
Dna Binding Specificity ◽  
Octamer Motif ◽  
Better Than

The ubiquitously expressed mammalian POU-domain protein Oct-1 specifically recognizes two classes of cis-acting regulatory elements that bear little sequence similarity, the octamer motif ATGCAAAT and the TAATGARAT motif. The related pituitary-specific POU protein Pit-1 also recognizes these two motifs but, unlike Oct-1, binds preferentially to the TAATGARAT motif. Yet in our assay, Pit-1 still binds octamer elements better than does the octamer motif-binding protein Oct-3. The POU domain is responsible for recognizing these diverse regulatory sequences through multiple DNA contacts that include the two POU subdomains, the POU-specific region, and the POU homeodomain. The DNA-binding properties of 10 chimeric POU domains, in which different POU-domain segments are derived from either Oct-1 or Pit-1, reveal a high degree of structural plasticity; these hybrid proteins all bind DNA well and frequently bind particular sites better than does either of the parental POU domains. In these chimeric POU domains, the POU-specific A and B boxes and the hypervariable POU linker can influence DNA-binding specificity. The surprising result is that the influence a particular segment has on DNA-binding specificity can be greatly affected by the origin of other segments of the POU domain and the sequence of the binding site. Thus, the broad but selective DNA-binding specificity of Oct-1 is conferred both by multiple DNA contacts and by dynamic interactions within the DNA-bound POU domain.

Sign in / Sign up

Export Citation Format

Share Document