Using Combined Methods of Genetic Mapping and Nanopore-Based Sequencing Technology to Analyze the Insertion Positions of G10evo-EPSPS and Cry1Ab/Cry2Aj Transgenes in Maize

The insertion position of the exogenous fragment sequence in a genetically modified organism (GMO) is important for the safety assessment and labeling of GMOs. SK12-5 is a newly developed transgenic maize line transformed with two trait genes [i.e., G10evo-5-enolpyrul-shikimate-3-phosphate synthase (EPSPS) and Cry1Ab/Cry2Aj] that was recently approved for commercial use in China. In this study, we tried to determine the insertion position of the exogenous fragment for SK12-5. The transgene–host left border and right border integration junctions were obtained from SK12-5 genomic DNA by using the thermal asymmetric interlaced polymerase chain reaction (TAIL-PCR) and next-generation Illumina sequencing technology. However, a Basic Local Alignment Search Tool (BLAST) analysis revealed that the flanking sequences in the maize genome are unspecific and that the insertion position is located in a repetitive sequence area in the maize genome. To locate the fine-scale insertion position in SK12-5, we combined the methods of genetic mapping and nanopore-based sequencing technology. From a classical bulked-segregant analysis (BSA), the insertion position in SK12-5 was mapped onto Bin9.03 of chromosome 9 between the simple sequence repeat (SSR) markers umc2337 and umc1743 (26,822,048–100,724,531 bp). The nanopore sequencing results uncovered 10 reads for which one end was mapped onto the vector and the other end was mapped onto the maize genome. These observations indicated that the exogenous T-DNA fragments were putatively integrated at the position from 82,329,568 to 82,379,296 bp of chromosome 9 in the transgenic maize SK12-5. This study is helpful for the safety assessment of the novel transgenic maize SK12-5 and shows that the combined method of genetic mapping and the nanopore-based sequencing technology will be a useful approach for identifying the insertion positions of transgenic sequences in other GM plants with relatively large and complex genomes.

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Faculty Opinions recommendation of Current Understanding of Food Safety Assessment Procedure for Stacked Trait Products Derived from Conventional Breeding among Approved GM Plants.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.737650380.793572964 ◽

2020 ◽

Author(s):

Laura Privalle

Keyword(s):

Food Safety ◽

Safety Assessment ◽

Current Understanding ◽

Assessment Procedure ◽

Conventional Breeding ◽

Gm Plants

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The Influence of Memory-Aware Computation on Distributed BLAST

Current Bioinformatics ◽

10.2174/1574893613666180601080811 ◽

2019 ◽

Vol 14 (2) ◽

pp. 157-163

Author(s):

Majid Hajibaba ◽

Mohsen Sharifi ◽

Saeid Gorgin

Keyword(s):

Search Time ◽

Genomic Research ◽

Local Alignment ◽

Negative Effects ◽

Sequencing Technologies ◽

Percent Improvement ◽

Fast Processing ◽

Search Tool ◽

Memory Awareness ◽

Generation Sequencing

Background: One of the pivotal challenges in nowadays genomic research domain is the fast processing of voluminous data such as the ones engendered by high-throughput Next-Generation Sequencing technologies. On the other hand, BLAST (Basic Local Alignment Search Tool), a longestablished and renowned tool in Bioinformatics, has shown to be incredibly slow in this regard. Objective: To improve the performance of BLAST in the processing of voluminous data, we have applied a novel memory-aware technique to BLAST for faster parallel processing of voluminous data. Method: We have used a master-worker model for the processing of voluminous data alongside a memory-aware technique in which the master partitions the whole data in equal chunks, one chunk for each worker, and consequently each worker further splits and formats its allocated data chunk according to the size of its memory. Each worker searches every split data one-by-one through a list of queries. Results: We have chosen a list of queries with different lengths to run insensitive searches in a huge database called UniProtKB/TrEMBL. Our experiments show 20 percent improvement in performance when workers used our proposed memory-aware technique compared to when they were not memory aware. Comparatively, experiments show even higher performance improvement, approximately 50 percent, when we applied our memory-aware technique to mpiBLAST. Conclusion: We have shown that memory-awareness in formatting bulky database, when running BLAST, can improve performance significantly, while preventing unexpected crashes in low-memory environments. Even though distributed computing attempts to mitigate search time by partitioning and distributing database portions, our memory-aware technique alleviates negative effects of page-faults on performance.

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Predicting bacteriophage hosts based on sequences of annotated receptor-binding proteins

Scientific Reports ◽

10.1038/s41598-021-81063-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Dimitri Boeckaerts ◽

Michiel Stock ◽

Bjorn Criel ◽

Hans Gerstmans ◽

Bernard De Baets ◽

...

Keyword(s):

Machine Learning ◽

Predictive Model ◽

Receptor Binding ◽

Bacterial Infections ◽

Sequence Data ◽

Sequence Similarity ◽

Area Under The Curve ◽

Local Alignment ◽

Search Tool ◽

Different Levels

AbstractNowadays, bacteriophages are increasingly considered as an alternative treatment for a variety of bacterial infections in cases where classical antibiotics have become ineffective. However, characterizing the host specificity of phages remains a labor- and time-intensive process. In order to alleviate this burden, we have developed a new machine-learning-based pipeline to predict bacteriophage hosts based on annotated receptor-binding protein (RBP) sequence data. We focus on predicting bacterial hosts from the ESKAPE group, Escherichia coli, Salmonella enterica and Clostridium difficile. We compare the performance of our predictive model with that of the widely used Basic Local Alignment Search Tool (BLAST). Our best-performing predictive model reaches Precision-Recall Area Under the Curve (PR-AUC) scores between 73.6 and 93.8% for different levels of sequence similarity in the collected data. Our model reaches a performance comparable to that of BLASTp when sequence similarity in the data is high and starts outperforming BLASTp when sequence similarity drops below 75%. Therefore, our machine learning methods can be especially useful in settings in which sequence similarity to other known sequences is low. Predicting the hosts of novel metagenomic RBP sequences could extend our toolbox to tune the host spectrum of phages or phage tail-like bacteriocins by swapping RBPs.

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Kelch 13-propeller polymorphisms in Plasmodium falciparum from Jazan region, southwest Saudi Arabia

Malaria Journal ◽

10.1186/s12936-020-03467-3 ◽

2020 ◽

Vol 19 (1) ◽

Author(s):

Ommer Mohammed Dafalla ◽

Mohammed Alzahrani ◽

Ahmed Sahli ◽

Mohammed Abdulla Al Helal ◽

Mohammad Mohammad Alhazmi ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Saudi Arabia ◽

Parasite Clearance ◽

Sub Saharan Africa ◽

Local Alignment ◽

Nucleotide Polymorphisms ◽

Gene Encoding ◽

Synonymous Mutations ◽

Search Tool ◽

Sub Saharan

Abstract Background Artemisinin-based combination therapy (ACT) is recommended at the initial phase for treatment of Plasmodium falciparum, to reduce morbidity and mortality in all countries where malaria is endemic. Polymorphism in portions of P. falciparum gene encoding kelch (K13)-propeller domains is associated with delayed parasite clearance after ACT. Of about 124 different non-synonymous mutations, 46 have been identified in Southeast Asia (SEA), 62 in sub-Saharan Africa (SSA) and 16 in both the regions. This is the first study designed to analyse the prevalence of polymorphism in the P. falciparum k13-propeller domain in the Jazan region of southwest Saudi Arabia, where malaria is endemic. Methods One-hundred and forty P. falciparum samples were collected from Jazan region of southwest Saudi Arabia at three different times: 20 samples in 2011, 40 samples in 2016 and 80 samples in 2020 after the implementation of ACT. Plasmodium falciparum kelch13 (k13) gene DNA was extracted, amplified, sequenced, and analysed using a basic local alignment search tool (BLAST). Results This study obtained 51 non-synonymous (NS) mutations in three time groups, divided as follows: 6 single nucleotide polymorphisms (SNPs) ‘11.8%’ in samples collected in 2011 only, 3 (5.9%) in 2011and 2016, 5 (9.8%) in 2011 and 2020, 5 (9.8%) in 2016 only, 8 (15.7%) in 2016 and 2020, 14 (27.5%) in 2020 and 10 (19.6%) in all the groups. The BLAST revealed that the 2011 isolates were genetically closer to African isolates (53.3%) than Asian ones (46.7%). Interestingly, this proportion changed completely in 2020, to become closer to Asian isolates (81.6%) than to African ones (18.4%). Conclusions Despite the diversity of the identified mutations in the k13-propeller gene, these data did not report widespread artemisinin-resistant polymorphisms in the Jazan region where these samples were collected. Such a process would be expected to increase frequencies of mutations associated with the resistance of ACT.

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A heterochromatic knob reducing the flowering time in maize

10.1101/2021.03.31.437909 ◽

2021 ◽

Author(s):

Renata Flavia Carvalho ◽

Margarida L. R. Aguiar-Perecin ◽

Wellington Ronildo Clarindo ◽

Roberto F Fritsche Neto ◽

Mateus Mondin

Keyword(s):

Genetic Mapping ◽

Association Study ◽

Flowering Time ◽

Genome Size ◽

Inbred Lines ◽

Agronomic Trait ◽

Chromosome 9 ◽

Homozygous State ◽

Allele Substitution

Maize flowering time is an important agronomic trait, which is associated with variations in the genome size and heterochromatic knobs content. We integrated three steps to show this association. Firstly, we selected inbred lines varying for heterochromatic knob composition at specific sites in the homozygous state. Then, we produced heterozygous hybrids for knobs, which allow us to carry out genetic mapping. Second, we measured the genome size and flowering time for all materials. Knob composition did not affect the genome size. Finally, we developed an association study and identified a knob marker on chromosome 9 showing the strongest association with flowering time. Indeed, modeling allele substitution and dominance effects could offer only one heterochromatic knob locus that could affect flowering time, making it earlier rather than the knob composition.

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Fish Identification based on Partial Fragments of The Mitochondrial COI Subunit I Gene

E3S Web of Conferences ◽

10.1051/e3sconf/202132201038 ◽

2021 ◽

Vol 322 ◽

pp. 01038

Author(s):

Tuah N. M. Wulandari

Keyword(s):

Phylogenetic Tree ◽

Coi Gene ◽

Local Alignment ◽

Mtdna Sequences ◽

Mitochondrial Coi ◽

Search Tool ◽

Very High ◽

I Gene

The mtDNA sequences revealed that several of the fish studied were Hampala macrolepidota and Barbonymus gonionotus. The objective of this research was to learn the pattern of COI gene in mtDNA and establish a phylogenetic tree. Basic Local Alignment Search Tool-nucleotide (BLASTn) confirmed that Barbonymus gonionotus froma the Ranau Lake, South Sumatera has 100% matching ranges to the species from Memberamo River (Indonesia), India, Bangladesh, Thailand (Mae Khlong), Indo-Myanmar, and Malaysia_1. The lowest closeness (98.76%) is related to species from Thailand (Lower Ing). The Blast investigation appears us that the level of familiarity was very high, it is coming to 98-100% in Barbonymus gonionotus. Hampala macrolepidota had 100% matching ranges to the species from Indonesia (SouthaSumatera_1) and Vietnam. They had 99.05%-99.84% closeness from Malaysia_1,2&3, Indonesia (South Sumatera_2&3, Java and Bali_1,2&3).

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A Case Report on Genetic Analysis of Exon2 of Thyroid Transcription Factor 2 Gene in Congenital Hypothyroidism Patient

European Journal of Medical and Health Sciences ◽

10.24018/ejmed.2021.3.2.744 ◽

2021 ◽

Vol 3 (2) ◽

pp. 19-21

Author(s):

Marjia Khatun ◽

Laila Anjuman Banu

Keyword(s):

Transcription Factor ◽

Pediatric Patient ◽

Congenital Hypothyroidism ◽

Sanger Sequencing ◽

Demographic Data ◽

Local Alignment ◽

Cycle Sequencing ◽

Thyroid Transcription Factor ◽

Search Tool ◽

Information Database

A-3-year- old Bangladeshi pediatric patient named Tasin was presented with a diagnosed case of congenital hypothyroidism (CH). This type of hypothyroidism may occur due to the alteration in the nucleotide sequences of the Thyroid transcription factor 2 gene. Few studies are present on the genetic basis of this disease. CH is common in Bangladesh, may be due to geographical variation or other causes. Therefore, this study was conducted to identify whether there was any genetic alteration in the exon2 of Thyroid transcription factor 2 gene. With due procedure and permission from the guardian of the pediatric patient, socio-demographic data was collected. Isolation of DNA, quantitation and qualitation of DNA was ensured, polymerase chain reaction (PCR) was performed, the amplicons that was obtained from PCR; validated visually by gel electrophoresis methods; cycle sequencing was performed by Sanger sequencing. The chromatogram data that was obtained from Sanger sequencing was analyzed and compared with the National Center for Biotechnology Information database by Basic Local Alignment Search Tool search. Sanger sequencing revealed substitution (c.1051G>T) in the Sequence Tagged Site of the exon2 of Thyroid transcription factor 2 gene and this is new variants and not reported in National Center for Biotechnology Information database.

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