scholarly journals H 2 A . Z / H 2 B . Z double‐variant nucleosomes inhabit the AT ‐rich promoter regions of the P lasmodium falciparum genome

2013 ◽  
Vol 87 (5) ◽  
pp. 1061-1073 ◽  
Author(s):  
Wieteke A. M. Hoeijmakers ◽  
Adriana M. Salcedo‐Amaya ◽  
Arne H. Smits ◽  
Kees‐Jan Françoijs ◽  
Moritz Treeck ◽  
...  
Keyword(s):  
Falciparum Genome ◽  
Promoter Regions

Optimization of the Expression of 1,3-1,4-β-glucanase Gene from Rhizomucor miehei in the Komagataella kurtzmanii yeast

2019 ◽  
Vol 35 (5) ◽  
pp. 3-11 ◽  
Author(s):  
I.I. Gubaidullin ◽  
A.S. Fedorov ◽  
D.G. Kozlov
Keyword(s):  
Target Gene ◽  
Rhizomucor Miehei ◽  
Leader Peptide ◽  
Promoter Regions ◽  
Functional Elements ◽  
Resource Center ◽  
The Status ◽  
Pichia Pastoris Yeast ◽  
The Difference ◽  
Genetic Constructs

Key functional elements of the vector (promoter, leader and terminator regions) that provide the expression of a target l,3-l,4-(3-glucanase gene from Rhizomucor miehei in the Komagataella kurtzmanii yeast have been optimized. It was shown that the promoter regions of the gene AOX1 from the Pichia pastoris yeast currently reclassified as Komagataella phaffti and from К. kurtzmanii yeast as parts of a vector provided equal levels of expression of the target gene in the cells of the recipient strain К. kurtzmanii Y727his4, i.e. they were completely interchangeable. This means that genetic constructs that were previously developed for the biosynthesis of recombinant proteins in К. phajfii are able to provide an effective expression in the К kurtzmanii yeast. The leader peptide MF4I (used as a variant of mif4I containing one amino acid substitution) and the leader peptide maxHH (containing the double proregion of the Hspl50 protein from Saccharomyces cerevisiae) confirmed the status of the most powerful elements among the five leader sequences analyzed. Their efficiency was 1.7 times higher than that of the standard leader from the yeast alpha-factor, and by 20% higher than the characteristics of the second group of artificial leaders. At the same time, it was found that, the choice of the terminator region had the strongest influence on the expression of the target gene among all of the vector functional elements. The best terminator elements were variants derived from the transcription termination region of the AOX1 gene, and the difference in the expression level of the target gene using different terminators was approximately 4.5 times. Based on the analysis of the obtained data, the optimal composition of the key functional elements of the expression vector was determined ; it included the promoter and terminator regions of the AOX1 yeast gene and one of the artificial leaders, mif4I or maxHH. β-glucanase, Komagataella kurtzmanii, yeast, secretion, strain producer The work was financially supported by the Ministry of Science and Higher education of the Russian Federation (Unique Project Identifier RFMEFI60717X0179) using the Unique Scientific Facility of the National Bio-Resource Center «All-Russian Collection of Industrial Microorganisms», NRC «Kurchatov Institute» - GOSNIIGENETIKA

ZFARED: A Database of the Antioxidant Response Elements in Zebrafish

2020 ◽  
Vol 15 (5) ◽  
pp. 415-419
Author(s):  
Azhwar Raghunath ◽  
Raju Nagarajan ◽  
Ekambaram Perumal
Keyword(s):  
Target Genes ◽  
Antioxidant Response ◽  
Zebrafish Genome ◽  
Promoter Regions ◽  
Protein Coding ◽  
Response Elements ◽  
Toxic Agents ◽  
Upstream Promoter ◽  
Its Gene ◽  
Antioxidant Response Elements

Background: Antioxidant Response Elements (ARE) play a key role in the expression of Nrf2 target genes by regulating the Keap1-Nrf2-ARE pathway, which offers protection against toxic agents and oxidative stress-induced diseases. Objective: To develop a database of putative AREs for all the genes in the zebrafish genome. This database will be helpful for researchers to investigate Nrf2 regulatory mechanisms in detail. Methods: To facilitate researchers functionally characterize zebrafish AREs, we have developed a database of AREs, Zebrafish Antioxidant Response Element Database (ZFARED), for all the protein-coding genes including antioxidant and mitochondrial genes in the zebrafish genome. The front end of the database was developed using HTML, JavaScript, and CSS and tested in different browsers. The back end of the database was developed using Perl scripts and Perl-CGI and Perl- DBI modules. Results: ZFARED is the first database on the AREs in zebrafish, which facilitates fast and efficient searching of AREs. AREs were identified using the in-house developed Perl algorithms and the database was developed using HTML, JavaScript, and Perl-CGI scripts. From this database, researchers can access the AREs based on chromosome number (1 to 25 and M for mitochondria), strand (positive or negative), ARE pattern and keywords. Users can also specify the size of the upstream/promoter regions (5 to 30 kb) from transcription start site to access the AREs located in those specific regions. Conclusion: ZFARED will be useful in the investigation of the Keap1-Nrf2-ARE pathway and its gene regulation. ZFARED is freely available at http://zfared.buc.edu.in/.

scholarly journals Novel Transcriptional Regulons for Autotrophic Cycle Genes in Crenarchaeota

2015 ◽  
Vol 197 (14) ◽  
pp. 2383-2391 ◽  
Author(s):  
Semen A. Leyn ◽  
Irina A. Rodionova ◽  
Xiaoqing Li ◽  
Dmitry A. Rodionov
Keyword(s):  
Carbon Dioxide ◽  
Transcriptional Regulation ◽  
Comparative Genomics ◽  
Dna Binding ◽  
Transcriptional Control ◽  
Binding Assays ◽  
Promoter Regions ◽  
Content Type ◽  
Genome Context

ABSTRACTAutotrophic microorganisms are able to utilize carbon dioxide as their only carbon source, or, alternatively, many of them can grow heterotrophically on organics. Different variants of autotrophic pathways have been identified in various lineages of the phylumCrenarchaeota. Aerobic members of the orderSulfolobalesutilize the hydroxypropionate-hydroxybutyrate cycle (HHC) to fix inorganic carbon, whereas anaerobicThermoprotealesuse the dicarboxylate-hydroxybutyrate cycle (DHC). Knowledge of transcriptional regulation of autotrophic pathways inArchaeais limited. We applied a comparative genomics approach to predict novel autotrophic regulons in theCrenarchaeota. We report identification of two novel DNA motifs associated with the autotrophic pathway genes in theSulfolobales(HHC box) andThermoproteales(DHC box). Based on genome context evidence, the HHC box regulon was attributed to a novel transcription factor from the TrmB family named HhcR. Orthologs of HhcR are present in allSulfolobalesgenomes but were not found in other lineages. A predicted HHC box regulatory motif was confirmed byin vitrobinding assays with the recombinant HhcR protein fromMetallosphaera yellowstonensis. For the DHC box regulon, we assigned a different potential regulator, named DhcR, which is restricted to the orderThermoproteales. DhcR inThermoproteus neutrophilus(Tneu_0751) was previously identified as a DNA-binding protein with high affinity for the promoter regions of two autotrophic operons. The global HhcR and DhcR regulons reconstructed by comparative genomics were reconciled with available omics data inMetallosphaeraandThermoproteusspp. The identified regulons constitute two novel mechanisms for transcriptional control of autotrophic pathways in theCrenarchaeota.IMPORTANCELittle is known about transcriptional regulation of carbon dioxide fixation pathways inArchaea. We previously applied the comparative genomics approach for reconstruction of DtxR family regulons in diverse lineages ofArchaea. Here, we utilize similar computational approaches to identify novel regulatory motifs for genes that are autotrophically induced in microorganisms from two lineages ofCrenarchaeotaand to reconstruct the respective regulons. The predicted novel regulons in archaeal genomes control the majority of autotrophic pathway genes and also other carbon and energy metabolism genes. The HhcR regulon was experimentally validated by DNA-binding assays inMetallosphaeraspp. Novel regulons described for the first time in this work provide a basis for understanding the mechanisms of transcriptional regulation of autotrophic pathways inArchaea.

scholarly journals Genes encoding components of the olfactory signal transduction cascade contain a DNA binding site that may direct neuronal expression.

1993 ◽  
Vol 13 (9) ◽  
pp. 5805-5813 ◽  
Author(s):  
M M Wang ◽  
R Y Tsai ◽  
K A Schrader ◽  
R R Reed
Keyword(s):  
Signal Transduction ◽  
Dna Binding ◽  
Binding Site ◽  
Binding Sites ◽  
Consensus Sequence ◽  
Initiation Site ◽  
Olfactory Neuron ◽  
Promoter Regions ◽  
Transcriptional Initiation ◽  
Genes Encoding

Genes which mediate odorant signal transduction are expressed at high levels in neurons of the olfactory epithelium. The molecular mechanism governing the restricted expression of these genes likely involves tissue-specific DNA binding proteins which coordinately activate transcription through sequence-specific interactions with olfactory promoter regions. We have identified binding sites for the olfactory neuron-specific transcription factor, Olf-1, in the sequences surrounding the transcriptional initiation site of five olfactory neuron-specific genes. The Olf-1 binding sites described define the consensus sequence YTCCCYRGGGAR. In addition, we have identified a second binding site, the U site, in the olfactory cyclic nucleotide gated channel and type III cyclase promoters, which binds factors present in all tissue examined. These experiments support a model in which expression of Olf-1 in the sensory neurons coordinately activates a set of olfactory neuron-specific genes. Furthermore, expression of a subset of these genes may be modulated by additional binding factors.

scholarly journals GAA Trinucleotide Repeat Region Regulates M9/pMGA Gene Expression in Mycoplasma gallisepticum

2000 ◽  
Vol 68 (2) ◽  
pp. 871-876 ◽  
Author(s):  
Li Liu ◽  
Kevin Dybvig ◽  
Victor S. Panangala ◽  
Vicky L. van Santen ◽  
Christopher T. French
Keyword(s):  
Gene Expression ◽  
Trinucleotide Repeat ◽  
Mycoplasma Gallisepticum ◽  
Avian Host ◽  
Phase Variable ◽  
Repeat Region ◽  
Chromosomal Dna ◽  
Promoter Regions ◽  
Variable Expression ◽  
Gaa Repeats

ABSTRACT Mycoplasma gallisepticum, the cause of chronic respiratory infections in the avian host, possesses a family of M9/pMGA genes encoding an adhesin(s) associated with hemagglutination. Nucleotide sequences of M9/pMGA gene family members indicate extensive sequence similarity in the promoter regions of both the transcribed and silent genes. The mechanism that regulates M9/pMGA gene expression is unknown, but studies have revealed an apparent correlation between gene expression and the number of tandem GAA repeat motifs located upstream of the putative promoter. In this study, transposon Tn4001was used as a vector with the Escherichia coli lacZ gene as the reporter system to examine the role of the GAA repeats in M9/pMGA gene expression in M. gallisepticum. A 336-bp M9 gene fragment (containing the GAA repeat region, the promoter, and the translation start codon) was amplified by PCR, ligated with alacZ gene from E. coli, and inserted into the Tn4001-containing plasmid pISM2062. This construct was transformed into M. gallisepticum PG31. Transformants were filter cloned on agar supplemented with 5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside (X-Gal) to monitor lacZ gene expression on the basis of blue/white color selection. Several cycles of filter cloning resulted in cell lineages in which lacZ gene expression alternated between the On and Off states in successive generations of progeny clones. The promoter regions of the M9-lacZ hybrid genes of individual progeny clones were amplified by PCR and sequenced. The only differences between the promoter regions of the blue and white colonies were in the number of GAA repeats. Clones that expressedlacZ had exactly 12 tandem copies of the GAA repeat. Clones that did not express lacZ invariably had either more than 12 (14 to 16) or fewer than 12 (5 to 11) GAA repeats. Southern analysis of M. gallisepticum chromosomal DNA confirmed that the phase-variable expression of the lacZ reporter gene was not caused by Tn4001 transposition. These data strongly indicate that changes in the length of the GAA repeat region are responsible for regulating M9/pMGA gene expression.

scholarly journals Further Studies on the 3-Ketosteroid 9α-Hydroxylase of Rhodococcus ruber Chol-4, a Rieske Oxygenase of the Steroid Degradation Pathway

2021 ◽  
Vol 9 (6) ◽  
pp. 1171
Author(s):  
Sara Baldanta ◽  
Juana María Navarro Llorens ◽  
Govinda Guevara
Keyword(s):  
Cholesterol Metabolism ◽  
Genetic Regulation ◽  
Degradation Pathway ◽  
Rhodococcus Ruber ◽  
Promoter Regions ◽  
Steroid Nucleus ◽  
Steroid Substrate ◽  
Fine Regulation ◽  
Rieske Oxygenase ◽  
Steroid Catabolism

The biochemistry and genetics of the bacterial steroid catabolism have been extensively studied during the last years and their findings have been essential to the development of biotechnological applications. For instance, metabolic engineering of the steroid-eater strains has allowed to obtain intermediaries of industrial value. However, there are still some drawbacks that must be overcome, such as the redundancy of the steroid catabolism genes in the genome and a better knowledge of its genetic regulation. KshABs and KstDs are key enzymes involved in the aerobic breakage of the steroid nucleus. Rhodococcus ruber Chol-4 contains three kshAs genes, a single kshB gene and three kstDs genes within its genome. In the present work, the growth of R. ruber ΔkshA strains was evaluated on different steroids substrates; the promoter regions of these genes were analyzed; and their expression was followed by qRT-PCR in both wild type and ksh mutants. Additionally, the transcription level of the kstDs genes was studied in the ksh mutants. The results show that KshA2B and KshA1B are involved in AD metabolism, while KshA3B and KshA1B contribute to the cholesterol metabolism in R. ruber. In the kshA single mutants, expression of the remaining kshA and kstD genes is re-organized to survive on the steroid substrate. These data give insight into the fine regulation of steroid genes when several isoforms are present.

Sign in / Sign up

Export Citation Format

Share Document