Search results

1

Mapping of a transcription promoter located inside the priA gene of the Bacillus subtilis chromosome

100%

Hinc K., Iwanicki A., Seror S., Obuchowski M.

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2006

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vol. 53

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issue 3

497-505

EN

The genome sequence of the Gram-positive soil bacterium Bacillus subtilis was completed in 1997 (Kunst et al., 1998) and the results included the identification of a putative transcription unit encompassing the yloI to yloS genes. Within this region of the B. subtilis chromosome 11 putative open reading frames were found with a wide diversity of probable functions. In this work we have analyzed transcription in the region of the priA-cpgA genes and we have mapped a promoter which is located inside the priA gene and its activity directs transcription of the def-yloM genes. Moreover, this transcript can be extended at low level to the prpC-priK-cpgA genes. Analysis of the sequence in proximity of the transcription start site revealed a sequence suitable for the housekeeping σA subunit of RNA polymerase. Analysis of the β-glactosidase activity of transcription fusions revealed that the identified promoter is active at low level and its activity is increased during late exponential phase of growth.

2

Properties of Escherichia coli RNA polymerase from a strain devoid of the stringent response alarmone ppGpp

100%

Szalewska-Pałasz A.

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2008

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vol. 55

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issue 2

317-323

EN

The stringent response alarmone guanosine tetraphosphate (ppGpp) affects transcription from many promoters. ppGpp binds directly to the transcription enzyme of Escherichia coli, RNA polymerase. Analysis of the crystal structure of RNA polymerase with ppGpp suggested that binding of this nucleotide may result in some conformational or post-translational alterations to the enzyme. These changes might affect in vitro performance of the enzyme. Here, a comparison of the in vitro properties of RNA polymerases isolated from wild type and ppGpp-deficient bacteria shows that both enzymes do not differ in i) transcription activity of various promoters (e.g. σ70-rrnB P1, λpL, T7A1), ii) response to ppGpp, iii) promoter-RNA polymerase open complex stability. Thus, it may be concluded that ppGpp present in the bacterial cell prior to purification of the RNA polymerase does not result in the alterations to the enzyme that could be permanent and affect its in vitro transcription capacity.

3

The relation of transcription to memory formation.

100%

Korzus E.

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2003

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vol. 50

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issue 3

775-782

EN

A distinction between short-term memories lasting minutes to hours and long-term memories lasting for many days is that the formation of long-term memories requires new gene expression. In this review, the focus is on the current understanding of the relation of transcription to memory consolidation based on the data collected from behavioral studies performed primarily on genetically altered animals. Studies in Drosophila and Aplysia indicate that the transcription factor cAMP/Ca2+ response element binding protein (CREB) is critical in mediating the conversion from short- to long-term memory. More recent genetic studies in mice also demonstrated CREB and inducible transcription factor Zif268 involvement in information storage processes. Transcription seems to play essential role in memory formation but the mechanisms for activation of transcription and downstream processes during memory consolidation remain unclear.

4

Cohesin Irr1/Scc3 is likely to influence transcription in Saccharomyces cerevisiae via interaction with Mediator complex

100%

Cena A., Skoneczny M., Chełstowska A., Kowalec P., Natorff R., Kurlandzka A.

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2013

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vol. 60

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issue 2

233-238

EN

The evolutionarily conserved proteins forming sister chromatid cohesion complex are also involved in the regulation of gene transcription. The participation of SA2p (mammalian ortholog of yeast Irr1p, associated with the core of the complex) in the regulation of transcription is already described. Here we analyzed microarray profiles of gene expression of a Saccharomyces cerevisiae irr1-1/IRR1 heterozygous diploid strain. We report that expression of 33 genes is affected by the presence of the mutated Irr1-1p and identify those genes. This supports the suggested role of Irr1p in the regulation of transcription. We also indicate that Irr1p may interact with elements of transcriptional coactivator Mediator.

5

Two pathogenic mutations located within the 5'-regulatory sequence of the GJB1 gene affecting initiation of transcription and translation

88%

Kabzińska D., Kotruchow K., Ryniewicz B., Kochański A.

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2011

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vol. 58

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issue 3

359-363

EN

In contrast to mutations in the coding sequences of a genes involved in the pathogenesis of Charcot-Marie-Tooth disease (CMT), little is known about CMT phenotypes resulting from a DNA variants located in regulatory sequences of a given " CMT gene". Charcot-Marie-Tooth type X1 disease (CMTX1) is caused by mutations in the GJB1 gene coding for an ion channel known as connexin, with a molecular mass of 32 kDa (Cx32). Only 0.01% of the GJB1 gene mutations have been reported in its 5' regulatory sequence. Pathogenic mutations occured in the internal ribosome entry site (IRES) are extremely rarely reported in human genetic disorders. To the best of our knowledge, in this study we report for the first time in an Eastern European population, two CMTX1 families in which two pathogenic mutations in the 5' regulatory sequence of the GJB1 gene (c.-529T>C and -459C>T) have been found. The two mutations identified in our study disturb the 5' UTR sequence in two different ways, by affecting the transcription factor SOX10 binding site (c.-529T>C) and by the disrupting IRES element of GJB1 gene (c.-459C>T). These regions are responsible for transcription (SOX10) and initiation of translation (IRES), respectively. On the basis of our findings that, in contrast to the most DNA sequence variants reported in untranslated regulatory regions of genes, the c.-459C>T and c.-529T>C mutations remain pathogenic in the context of different ethnic background.

6

Functional and physical interactions of Krr1p, a Saccharomyces cerevisiae nucleolar protein.

88%

Gromadka R., Karkusiewicz I., Rempoła B., Rytka J.

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vol. 51

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issue 1

173-187

EN

The Krr1 protein of Saccharomyces cerevisiae is involved in processing of pre-rRNA and assembly of pre-ribosomal 40S subunits. To further investigate the function of Krr1p we constructed a conditional cold sensitive mutant krr1-21, and isolated seven genes from Schizosaccharomyces pombe whose products suppressed the cold sensitive phenotype of krr1-21 cells. Among the multicopy suppressors we found genes coding for translation elongation factor EF-1α, a putative ribose methyltransferase and five genes encoding ribosomal proteins. Using the tandem affinity purification (TAP) method we identified thirteen S. cerevisiae ribosomal proteins interacting with Krr1p. Taken together, these results indicate that Krr1p interacts functionally as well as physically with ribosomal proteins. Northern blot analysis revealed that changes in the level of krr1-21 mRNA were accompanied by similar changes in the level of mRNAs of genes encoding ribosomal proteins. Thus, Krr1p and the genes encoding ribosomal proteins it interacts with seem to be coordinately regulated at the level of transcription.

7

The HPV16 E2 transcriptional regulator mode of action depends on the physical state of the viral genome

75%

Schmidt M. T., Olejnik A. K., Goździcka-Józefiak A.

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2005

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vol. 52

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issue 4

823-832

EN

Human papillomavirus (HPV) infection is a major risk factor for the development of cervical cancer. The HPV-induced immortalization of epithelial cell usually requires integration of the viral DNA into the host cell genome. The integration event causes disruption of the E2 gene and this is followed by overexpression of the E6 and E7 oncoproteins. The E2 protein is a transcription factor that regulates expression of the E6 and E7 oncoproteins by binding to four sites within the viral long control region. We used an in vitro cell culture model to explore the role of the E2 protein in the transcriptional control of the HPV16 long control region. Employing transient and stable transfection experiments we simulated the episomal and integrated states of the viral genome, respectively. We show that the E2 protein up-regulates E6/E7 transcription from episomal DNA but represses it in the case of integrated DNA. The activator function of the E2 protein seems to counteract the repressive chromatin structure formed over episomal DNA. Steroid hormones and retinol also modulate oncogene transcription differently depending on the physical structure of the viral DNA. Our data suggest regulatory mechanisms involving interactions between the E2 protein and nuclear hormone receptors.

8

The role of the 5' terminal region of p53 mRNA in the p53 gene expression

75%

Swiatkowska A., Zydowicz P., Sroka J., Ciesiołka J.

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2016

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vol. 63

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issue 4

645-651

EN

The p53 tumour suppressor protein is one of the major factors responsible for cell cycle regulation and protection against cancer development. This is why it is often referred to as "the guardian of the genome". On the other hand, mutations in the p53 gene are connected with more than 50% of tumours of various types. The thirty-six years of extensive research on the p53 gene and its protein products have shown how sophisticated the p53-based cell system control is. An additional level of complexity of the p53 research is connected with at least twelve p53 isoforms which have been identified in the cell. Importantly, disturbance of the p53 isoforms' expression seems to play a key role in tumorigenesis, cell differentiation and cell response to pathogenic bacteria, and RNA and DNA viruses. Expression of various p53 isoforms results from the usage of different transcription promoters, alternative splicing events and translation initiation from alternative AUG codons. The importance of the 5'-terminal regions of different p53 mRNA transcripts in the multi-level regulation of the p53 gene has recently been documented. In this review we focus on the structural features of these regions and their specific role in the p53 translation initiation process.

9

System for Automatic Transcription of Sessions of the Polish Senate

75%

Marasek K., Koržinek D., Brocki Ł.

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10

Aktyna i miozyny w jądrze komórkowym

51%

Nowak J., Rędowicz M.

Kosmos

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2018

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vol. 67

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issue 1

75-93

PL

Aktyna i miozyna to białka kojarzone przede wszystkim z ich kluczową rolą w generacji skurczu mięśni. Natomiast poza izoformami charakterystycznymi dla mięśni są również izoformy aktyny i miozyny, które występują we wszystkich typach komórek i tkanek (patrz artykuł Suszek i współaut. w tym zeszycie KOSMOSU). Badania prowadzone w ostatnich dwóch dekadach wykazały niezbicie, że zarówno aktyna (i szereg białek wiążących aktynę) oraz liczne miozyny (przedstawiciele rodzin I, II, V, VI, XVI i XVIII) lokalizują się w jądrze komórkowym gdzie są zaangażowane w procesy transkrypcji i naprawy DNA, transport w nukleoplazmie oraz import i eksport jądrowy, a także w utrzymywanie architektury jądra. Niniejszy artykuł opisuje dotychczasowy stan wiedzy o roli układu akto-miozynowego w jądrze komórkowym.

EN

Actin and myosins are the proteins mainly known from their key roles in muscle contraction. However, besides typical muscle isoforms there are actins and myosins that are present in all cell and tissue types. Studies performed within the last two decades have irrefutably shown that both the cytoplasmic actin isoforms (along with numerous actin-binding proteins) as well as many myosins (representing class I, II, V, VI, XVI and XVIII) are present within the nucleus. They play important roles in nuclear processes as they are involved in transcription and DNA repair, intranuclear transport as well as nuclear import and export, and in maintenance of nuclear architecture. This article describes the current knowledge on the acto-myosin system in this biggest cellular compartment.

Refine search results

Mapping of a transcription promoter located inside the priA gene of the Bacillus subtilis chromosome

Properties of Escherichia coli RNA polymerase from a strain devoid of the stringent response alarmone ppGpp

The relation of transcription to memory formation.

Cohesin Irr1/Scc3 is likely to influence transcription in Saccharomyces cerevisiae via interaction with Mediator complex

Two pathogenic mutations located within the 5'-regulatory sequence of the GJB1 gene affecting initiation of transcription and translation

Functional and physical interactions of Krr1p, a Saccharomyces cerevisiae nucleolar protein.

The HPV16 E2 transcriptional regulator mode of action depends on the physical state of the viral genome

The role of the 5' terminal region of p53 mRNA in the p53 gene expression

System for Automatic Transcription of Sessions of the Polish Senate

Aktyna i miozyny w jądrze komórkowym