scholarly journals Construction and Evaluation of Self-Directing Expression System Using Regulatory Elements of Cry Gene of Bacillus Thuringiensis

Author(s):  
Drishtant Singh ◽  
Samiksha . ◽  
Seema Madhumal Thayil ◽  
Satwinder Kaur Sohal ◽  
Anup Kumar Kesavan

Abstract An expression system based on the cry gene regulatory elements was constructed. The Terminator region of cry gene from B. thuringiensis subsp. kurstaki HD-1 was cloned in pSG1151 plasmid downstream to gfpmut1. The promoter region of the cry gene was amplified to give three different reading frames. The Promoter region of cry gene was cloned in pSG1151T plasmid upstream to gfpmut1. The expression of GFP under the promoter/terminator expression system was evaluated by checking the expression of gfpmut1 under the same promoter. The GFP content of pSG1151 and three constructs; pDSA1, pDSA2 and pDSA3 were compared by fluorescence spectroscopy. The fluorescent intensity of pSG1151 and pDSA1 were compared at time interval of 6 hours upto 72 hours. Both the samples showed detectable fluorescence that increased with time up to 12 hours, but the increase in the fluorescence of pDSA1 was 3 times higher as compared to pSG1151. A cold peptidase gene was cloned under the control of the cry promoter. The transformed E.coli DH5α colonies were patched on skim milk agar plates and the clones of pSG1151CP and pDSA1CP were compared on the basis of zone of clearance. The zone of clearance of pDSA1CP was much higher as compared to that of pSG1151CP. The cell-free supernatant of Bacillus sp. S1DI 10 and recombinant pDSA1CP collected at different time points was assayed for the specific activity of the extracellular protease. At 72 hours the protease activity in pDSA1CP was 2.7 fold higher compared to that of wild Bacillus sp. S1DI 10.

Blood ◽  
1998 ◽  
Vol 92 (12) ◽  
pp. 4677-4690 ◽  
Author(s):  
Carlos Rı́us ◽  
Joshua D. Smith ◽  
Nuria Almendro ◽  
Carmen Langa ◽  
Luisa M. Botella ◽  
...  

Endoglin (CD105) is a cell surface component of the transforming growth factor-β (TGF-β) receptor complex highly expressed by endothelial cells. Mutations in the endoglin gene are responsible for the hereditary hemorrhagic telangiectasia type 1 (HHT1), also known as Osler-Weber-Rendu syndrome (OMIM 187300). This is an autosomal dominant vascular disorder probably caused by a haploinsufficiency mechanism displaying low levels of the normal protein. To understand the mechanisms underlying the regulated expression of endoglin, a genomic DNA clone containing 3.3 kb of the 5′-flanking sequence of the human endoglin gene has been isolated. The 5′-flanking region of the endoglin gene lacks consensus TATA and CAAT boxes, but contains two GC-rich regions and consensus motifs for Sp1, ets, GATA, AP-2, NFκB, and Mad, as well as TGF-β–, glucocorticoid-, vitamin D-, and estrogen-responsive elements. As determined by primer extension and 5′ RACE experiments, a cluster of transcriptional start sites was found to be located 350 bp upstream from the translation initiation codon. To analyze the endoglin promoter activity, the upstream −400/+341 fragment was fused to the luciferase gene and transient transfections were conducted in several cell types. This construct displayed a tissue-specific activity in human and bovine endothelial cells. Analysis of various deletion constructs showed the existence of a basal promoter region within the −81/+350 fragment as well as major transcriptional regulatory elements within the −400/−141 fragment. Electrophoretic mobility shift assays demonstrated the specific interaction of a member of the ets family with a consensus motif located at position −68. A promoter construct mutated at this ets sequence showed a much reduced activity as compared with the wild-type construct, supporting the involvement of this ets motif in the basal activity of the promoter. The endoglin promoter exhibited inducibility in the presence of TGF-β1, suggesting possible therapeutic treatments in HHT1 patients, in which the expression level of the normal endoglin allele might not reach the threshold required for its function. Isolation and characterization of the human endoglin promoter represents an initial step in elucidating the controlled expression of the endoglin gene.


Blood ◽  
1998 ◽  
Vol 92 (12) ◽  
pp. 4677-4690 ◽  
Author(s):  
Carlos Rı́us ◽  
Joshua D. Smith ◽  
Nuria Almendro ◽  
Carmen Langa ◽  
Luisa M. Botella ◽  
...  

Abstract Endoglin (CD105) is a cell surface component of the transforming growth factor-β (TGF-β) receptor complex highly expressed by endothelial cells. Mutations in the endoglin gene are responsible for the hereditary hemorrhagic telangiectasia type 1 (HHT1), also known as Osler-Weber-Rendu syndrome (OMIM 187300). This is an autosomal dominant vascular disorder probably caused by a haploinsufficiency mechanism displaying low levels of the normal protein. To understand the mechanisms underlying the regulated expression of endoglin, a genomic DNA clone containing 3.3 kb of the 5′-flanking sequence of the human endoglin gene has been isolated. The 5′-flanking region of the endoglin gene lacks consensus TATA and CAAT boxes, but contains two GC-rich regions and consensus motifs for Sp1, ets, GATA, AP-2, NFκB, and Mad, as well as TGF-β–, glucocorticoid-, vitamin D-, and estrogen-responsive elements. As determined by primer extension and 5′ RACE experiments, a cluster of transcriptional start sites was found to be located 350 bp upstream from the translation initiation codon. To analyze the endoglin promoter activity, the upstream −400/+341 fragment was fused to the luciferase gene and transient transfections were conducted in several cell types. This construct displayed a tissue-specific activity in human and bovine endothelial cells. Analysis of various deletion constructs showed the existence of a basal promoter region within the −81/+350 fragment as well as major transcriptional regulatory elements within the −400/−141 fragment. Electrophoretic mobility shift assays demonstrated the specific interaction of a member of the ets family with a consensus motif located at position −68. A promoter construct mutated at this ets sequence showed a much reduced activity as compared with the wild-type construct, supporting the involvement of this ets motif in the basal activity of the promoter. The endoglin promoter exhibited inducibility in the presence of TGF-β1, suggesting possible therapeutic treatments in HHT1 patients, in which the expression level of the normal endoglin allele might not reach the threshold required for its function. Isolation and characterization of the human endoglin promoter represents an initial step in elucidating the controlled expression of the endoglin gene.


2021 ◽  
Vol 10 (2) ◽  
pp. 186
Author(s):  
Asep Awaludin Prihanto ◽  
Kartika D. Aninta ◽  
Soffi Trisnaningrum

The need for protease in the industrial field has been increasing. Candidates for producing these enzymes can be isolated from the digestive tract of catfish (Clarias sp.). The purpose of this study was to obtain bacterial isolates that produce proteolytic from the gastrointestinal tract of catfish and determine the effect of different production media on the activity of proteolytic. The first step of this study was isolation, screening, and identification of bacteria. The second step was to test the effect of the media Luria Bertani, trypticase soy broth, and skim milk broth on proteolytic activity. Nineteen isolates were obtained from the screening process of proteolytic bacteria. Isolate no 1, was known as the best isolate in producing enzymes and was known as Bacillus sp. Tests with different growth media gave results that semi-quantitative, nutrient growth media produced the highest activity with a proteolytic index value of 2.09 ± 0.41. In addition, based on quantitative tests, the media Luria Bertani Broth produced the highest specific activity with a value of 36.479 U/mg. The conclusion of this study, Bacillus sp. from the gastrointestinal tract of catfish that cultured on the Luria Bertani Broth medium produced the best activity.


Genes ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1175
Author(s):  
Amarni L. Thomas ◽  
Judith Marsman ◽  
Jisha Antony ◽  
William Schierding ◽  
Justin M. O’Sullivan ◽  
...  

The RUNX1/AML1 gene encodes a developmental transcription factor that is an important regulator of haematopoiesis in vertebrates. Genetic disruptions to the RUNX1 gene are frequently associated with acute myeloid leukaemia. Gene regulatory elements (REs), such as enhancers located in non-coding DNA, are likely to be important for Runx1 transcription. Non-coding elements that modulate Runx1 expression have been investigated over several decades, but how and when these REs function remains poorly understood. Here we used bioinformatic methods and functional data to characterise the regulatory landscape of vertebrate Runx1. We identified REs that are conserved between human and mouse, many of which produce enhancer RNAs in diverse tissues. Genome-wide association studies detected single nucleotide polymorphisms in REs, some of which correlate with gene expression quantitative trait loci in tissues in which the RE is active. Our analyses also suggest that REs can be variant in haematological malignancies. In summary, our analysis identifies features of the RUNX1 regulatory landscape that are likely to be important for the regulation of this gene in normal and malignant haematopoiesis.


2021 ◽  
Vol 12 (2) ◽  
pp. 480-490
Author(s):  
Ahsanul Salehin ◽  
Ramesh Raj Puri ◽  
Md Hafizur Rahman Hafiz ◽  
Kazuhito Itoh

Colonization of a biofertilizer Bacillus sp. OYK strain, which was isolated from a soil, was compared with three rhizospheric and endophytic Bacillus sp. strains to evaluate the colonization potential of the Bacillus sp. strains with a different origin. Surface-sterilized seeds of tomato (Solanum lycopersicum L. cv. Chika) were sown in the sterilized vermiculite, and four Bacillus sp. strains were each inoculated onto the seed zone. After cultivation in a phytotron, plant growth parameters and populations of the inoculants in the root, shoot, and rhizosphere were determined. In addition, effects of co-inoculation and time interval inoculation of Bacillus sp. F-33 with the other endophytes were examined. All Bacillus sp. strains promoted plant growth except for Bacillus sp. RF-37, and populations of the rhizospheric and endophytic Bacillus sp. strains were 1.4–2.8 orders higher in the tomato plant than that of Bacillus sp. OYK. The plant growth promotion by Bacillus sp. F-33 was reduced by co-inoculation with the other endophytic strains: Klebsiella sp. Sal 1, Enterobacter sp. Sal 3, and Herbaspirillum sp. Sal 6., though the population of Bacillus sp. F-33 maintained or slightly decreased. When Klebsiella sp. Sal 1 was inoculated after Bacillus sp. F-33, the plant growth-promoting effects by Bacillus sp. F-33 were reduced without a reduction of its population, while when Bacillus sp. F-33 was inoculated after Klebsiella sp. Sal 1, the effects were increased in spite of the reduction of its population. Klebsiella sp. Sal 1 colonized dominantly under both conditions. The higher population of rhizospheric and endophytic Bacillus sp. in the plant suggests the importance of the origin of the strains for their colonization. The plant growth promotion and colonization potentials were independently affected by the co-existing microorganisms.


Genetics ◽  
2019 ◽  
Vol 212 (3) ◽  
pp. 729-742 ◽  
Author(s):  
Lena Annika Street ◽  
Ana Karina Morao ◽  
Lara Heermans Winterkorn ◽  
Chen-Yu Jiao ◽  
Sarah Elizabeth Albritton ◽  
...  

Condensins are evolutionarily conserved protein complexes that are required for chromosome segregation during cell division and genome organization during interphase. In Caenorhabditis elegans, a specialized condensin, which forms the core of the dosage compensation complex (DCC), binds to and represses X chromosome transcription. Here, we analyzed DCC localization and the effect of DCC depletion on histone modifications, transcription factor binding, and gene expression using chromatin immunoprecipitation sequencing and mRNA sequencing. Across the X, the DCC accumulates at accessible gene regulatory sites in active chromatin and not heterochromatin. The DCC is required for reducing the levels of activating histone modifications, including H3K4me3 and H3K27ac, but not repressive modification H3K9me3. In X-to-autosome fusion chromosomes, DCC spreading into the autosomal sequences locally reduces gene expression, thus establishing a direct link between DCC binding and repression. Together, our results indicate that DCC-mediated transcription repression is associated with a reduction in the activity of X chromosomal gene regulatory elements.


1997 ◽  
Vol 272 (6) ◽  
pp. 3444-3452 ◽  
Author(s):  
Allen D. Cooper ◽  
Jean Chen ◽  
Mary Jane Botelho-Yetkinler ◽  
Yicheng Cao ◽  
Takahiro Taniguchi ◽  
...  

2015 ◽  
Vol 2015 (1) ◽  
pp. pdb.top083642 ◽  
Author(s):  
Leila Taher ◽  
Leelavati Narlikar ◽  
Ivan Ovcharenko

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