scholarly journals BOX Elements Modulate Gene Expression in Streptococcus pneumoniae: Impact on the Fine-Tuning of Competence Development

2006 ◽  
Vol 188 (23) ◽  
pp. 8307-8312 ◽  
Author(s):  
Eivind Knutsen ◽  
Ola Johnsborg ◽  
Yves Quentin ◽  
Jean-Pierre Claverys ◽  
Leiv Sigve Håvarstein

ABSTRACT More than 100 BOX elements are randomly distributed in intergenic regions of the pneumococcal genome. Here we demonstrate that these elements can affect expression of neighboring genes and present evidence that they are mobile. Together, our findings show that BOX elements enhance genetic diversity and genomic plasticity in Streptococcus pneumoniae.

2002 ◽  
Vol 3 (4) ◽  
pp. 366-368 ◽  
Author(s):  
Jackie McCluskey ◽  
Christopher G. Dowson ◽  
Timothy J. Mitchell

Streptococcus pneumoniaeis an important human pathogen associated with pneumonia, septicaemia, meningitis and otitis media. It is estimated to result in over 3 million child deaths worldwide every year and an even greater number of deaths among the elderly. Prior to the complete sequencing of the genomes ofS. pneumoniaeTIGR4 (serotype 4) andS. pneumoniaeR6 (serotype 2), we designed a custom miniarray consisting of 497 pneumococcal genes. The overall objectives of our microarray investigations were, first, to assess the genetic diversity between differentS. pneumoniaeserotypes, clinical isolates and also differentStreptococcusspecies; second, we aimed to use microarray technology to examine the mechanisms by which environmental factors influence pneumococcal gene expression, and ultimately to further the understanding of how these changes in gene expression are achieved and how they may alter the virulence of the organism.


2019 ◽  
Vol 47 (7) ◽  
pp. e40-e40 ◽  
Author(s):  
Zhenghui Lu ◽  
Shihui Yang ◽  
Xin Yuan ◽  
Yunyun Shi ◽  
Li Ouyang ◽  
...  

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 991
Author(s):  
Fernanda Costa Brandão Berti ◽  
Sara Cristina Lobo-Alves ◽  
Camila de Freitas Oliveira-Toré ◽  
Amanda Salviano-Silva ◽  
Karen Brajão de Oliveira ◽  
...  

MicroRNAs (miRNAs) regulate gene expression by binding to complementary sequences within target mRNAs. Apart from working ‘solo’, miRNAs may interact in important molecular networks such as competing endogenous RNA (ceRNA) axes. By competing for a limited pool of miRNAs, transcripts such as long noncoding RNAs (lncRNAs) and mRNAs can regulate each other, fine-tuning gene expression. Several ceRNA networks led by different lncRNAs—described here as lncRNA-mediated ceRNAs—seem to play essential roles in cervical cancer (CC). By conducting an extensive search, we summarized networks involved in CC, highlighting the major impacts of such dynamic molecular changes over multiple cellular processes. Through the sponging of distinct miRNAs, some lncRNAs as HOTAIR, MALAT1, NEAT1, OIP5-AS1, and XIST trigger crucial molecular changes, ultimately increasing cell proliferation, migration, invasion, and inhibiting apoptosis. Likewise, several lncRNAs seem to be a sponge for important tumor-suppressive miRNAs (as miR-140-5p, miR-143-3p, miR-148a-3p, and miR-206), impairing such molecules from exerting a negative post-transcriptional regulation over target mRNAs. Curiously, some of the involved mRNAs code for important proteins such as PTEN, ROCK1, and MAPK1, known to modulate cell growth, proliferation, apoptosis, and adhesion in CC. Overall, we highlight important lncRNA-mediated functional interactions occurring in cervical cells and their closely related impact on cervical carcinogenesis.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Changhe Ji ◽  
Jakob Bader ◽  
Pradhipa Ramanathan ◽  
Luisa Hennlein ◽  
Felix Meissner ◽  
...  

AbstractGene expression requires tight coordination of the molecular machineries that mediate transcription and splicing. While the interplay between transcription kinetics and spliceosome fidelity has been investigated before, less is known about mechanisms regulating the assembly of the spliceosomal machinery in response to transcription changes. Here, we report an association of the Smn complex, which mediates spliceosomal snRNP biogenesis, with the 7SK complex involved in transcriptional regulation. We found that Smn interacts with the 7SK core components Larp7 and Mepce and specifically associates with 7SK subcomplexes containing hnRNP R. The association between Smn and 7SK complexes is enhanced upon transcriptional inhibition leading to reduced production of snRNPs. Taken together, our findings reveal a functional association of Smn and 7SK complexes that is governed by global changes in transcription. Thus, in addition to its canonical nuclear role in transcriptional regulation, 7SK has cytosolic functions in fine-tuning spliceosome production according to transcriptional demand.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Simon J. Moore ◽  
Yonek B. Hleba ◽  
Sarah Bischoff ◽  
David Bell ◽  
Karen M. Polizzi ◽  
...  

Abstract Background  A key focus of synthetic biology is to develop microbial or cell-free based biobased routes to value-added chemicals such as fragrances. Originally, we developed the EcoFlex system, a Golden Gate toolkit, to study genes/pathways flexibly using Escherichia coli heterologous expression. In this current work, we sought to use EcoFlex to optimise a synthetic raspberry ketone biosynthetic pathway. Raspberry ketone is a high-value (~ £20,000 kg−1) fine chemical farmed from raspberry (Rubeus rubrum) fruit. Results  By applying a synthetic biology led design-build-test-learn cycle approach, we refactor the raspberry ketone pathway from a low level of productivity (0.2 mg/L), to achieve a 65-fold (12.9 mg/L) improvement in production. We perform this optimisation at the prototype level (using microtiter plate cultures) with E. coli DH10β, as a routine cloning host. The use of E. coli DH10β facilitates the Golden Gate cloning process for the screening of combinatorial libraries. In addition, we also newly establish a novel colour-based phenotypic screen to identify productive clones quickly from solid/liquid culture. Conclusions  Our findings provide a stable raspberry ketone pathway that relies upon a natural feedstock (L-tyrosine) and uses only constitutive promoters to control gene expression. In conclusion we demonstrate the capability of EcoFlex for fine-tuning a model fine chemical pathway and provide a range of newly characterised promoter tools gene expression in E. coli.


1997 ◽  
Vol 107 (1) ◽  
pp. 1-10 ◽  
Author(s):  
D. Doenecke ◽  
W. Albig ◽  
C. Bode ◽  
B. Drabent ◽  
K. Franke ◽  
...  

2020 ◽  
Vol 88 ◽  
pp. S62
Author(s):  
Luis Galán Palma ◽  
Roshana Thambyrajah ◽  
Antonella Fidanza ◽  
Lesley Forrester ◽  
Pablo Menéndez ◽  
...  

Development ◽  
2000 ◽  
Vol 127 (15) ◽  
pp. 3305-3312 ◽  
Author(s):  
H.L. Ashe ◽  
M. Mannervik ◽  
M. Levine

The dorsal ectoderm of the Drosophila embryo is subdivided into different cell types by an activity gradient of two TGF(β) signaling molecules, Decapentaplegic (Dpp) and Screw (Scw). Patterning responses to this gradient depend on a secreted inhibitor, Short gastrulation (Sog) and a newly identified transcriptional repressor, Brinker (Brk), which are expressed in neurogenic regions that abut the dorsal ectoderm. Here we examine the expression of a number of Dpp target genes in transgenic embryos that contain ectopic stripes of Dpp, Sog and Brk expression. These studies suggest that the Dpp/Scw activity gradient directly specifies at least three distinct thresholds of gene expression in the dorsal ectoderm of gastrulating embryos. Brk was found to repress two target genes, tailup and pannier, that exhibit different limits of expression within the dorsal ectoderm. These results suggest that the Sog inhibitor and Brk repressor work in concert to establish sharp dorsolateral limits of gene expression. We also present evidence that the activation of Dpp/Scw target genes depends on the Drosophila homolog of the CBP histone acetyltransferase.


2013 ◽  
Vol 20 (5) ◽  
pp. 639-650 ◽  
Author(s):  
Katherine H. Restori ◽  
Mary J. Kennett ◽  
A. Catharine Ross

ABSTRACTVaccination reduces morbidity and mortality from pneumonia, but its effect on the tissue-level response to infection is still poorly understood. We evaluated pneumonia disease progression, acute-phase response, and lung gene expression profiles in mice inoculated intranasally with virulent Gram-positiveStreptococcus pneumoniaeserotype 3 (ST 3) with and without prior immunization with pneumococcal polysaccharide ST 3 (PPS3) or after coimmunization with PPS3 and a low dose of lipopolysaccharide (PPS3+LPS). Pneumonia severity was assessed in the acute phase at 5, 12, 24 and 48 h postinoculation (p.i.) and in the resolution phase at 7 days p.i. Primary PPS3-specific antibody production was upregulated, and IgM binding to pneumococci increased in PPS3-immunized mice. Immunizations with PPS3 or PPS3+LPS decreased bacterial recovery in the lung and blood at 24 and 48 h and increased survival. Microarray analysis of whole-lung RNA revealed significant changes in the acute-phase protein serum amyloid A (SAA) levels between noninfected and infected mice, and these changes were attenuated by immunization. SAA transcripts were higher in the liver and lungs of infected controls, and SAA protein was elevated in serum but decreased in PPS3-immunized mice. Thus, during a virulent pneumonia infection, prior immunization with PPS3 in an IgM-dependent manner as well as immunization with PPS3+LPS attenuated pneumonia severity and promoted resolution of infection, concomitant with significant regulation of cytokine gene expression levels in the lungs and acute-phase proteins in the lungs, liver, and serum.


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