scholarly journals RiceRelativesGD: a genomic database of rice relatives for rice research

Database ◽  
2019 ◽  
Vol 2019 ◽  
Author(s):  
Lingfeng Mao ◽  
Meihong Chen ◽  
Qinjie Chu ◽  
Lei Jia ◽  
Most Humaira Sultana ◽  
...  

Abstract Rice (Oryza sativa L.) is one of the most important crops worldwide. Its relatives, including phylogenetically related species of rice and paddy weeds with a similar ecological niche, can provide crucial genetic resources (such as resistance to biotic and abiotic stresses and high photosynthetic efficiency) for rice research. Although many rice genomic databases have been constructed, a database providing large-scale curated genomic data from rice relatives and offering specific gene resources is still lacking. Here, we present RiceRelativesGD, a user-friendly genomic database of rice relatives. RiceRelativesGD integrates large-scale genomic resources from 2 cultivated rice and 11 rice relatives, including 208 321 specific genes and 13 643 genes related to photosynthesis and responsive to external stimuli. Diverse bioinformatics tools are embedded in the database, which allow users to search, visualize and download the information of interest. To our knowledge, this is the first genomic database providing a centralized genetic resource of rice relatives. RiceRelativesGD will serve as a significant and comprehensive knowledgebase for the rice community.

2019 ◽  
Author(s):  
weimin dai ◽  
Yuan Wang ◽  
Yu-Jie Zhang ◽  
Xi-Xi Sun ◽  
Jin-Ling Yang ◽  
...  

Abstract Increasing resistance to aging is conducive to seed storage and germination rate of crop. Meanwhile, the resistance to aging is one of the important adaptive mechanisms of weed to thrive in farmland. Weedy rice (Oryza sativa f. spontanea) and cultivated rice (Oryza sativa L.) provide a unique pair demonstrating a weed and conspecific model crop that can be used to study the aging resistance of plants across a diverse geographical range. Chinese weedy rice derived from de-domestication of cultivated rice has rapidly risen to malignant weeds, though the hazard has only been reported for about 20 years. Whether weedy rice rapidly evolves higher seed aging resistance than cultivated rice during the process of dedomestication, which is conducive to its persistence in rice fields, is still unclear. In this experiment, the seeds of weed rice populations and their co-existing rice varieties were collected from 61 regions of China and germinated under normal and high temperatures for consecutive four years (2013–2016). Our study found that the aging resistance of weedy rice was higher than that of the co-existing rice cultivars, and weedy rice may have evolved a different aging resistance mechanism than rice cultivars and could be used as a germplasm resource to cultivate aging-resistant rice. The indica-type has strong aging resistance and no dormancy, while the japonica type has weak aging resistance and a little weak dormancy. Thus, by introducing indica-type aging-resistant alleles into japonica rice, cultivation of aging-resistant japonica rice could be possible.


2021 ◽  
Author(s):  
Clement Agret ◽  
Bastien Cazaux ◽  
Antoine Limasset

Motivation: To keep up with the scale of genomic databases, several methods rely on local sensitive hashing methods to efficiently find potential matches within large genome collections. Existing solutions rely on Minhash or Hyperloglog fingerprints and require reading the whole index to perform a query. Such solutions can not be considered scalable with the growing amount of documents to index. Results: We present NIQKI, a novel structure using well-designed fingerprints that lead to theoretical and practical query time improvements, outperforming state-of-the-art by orders of magnitude. Our contribution is threefold. First, we generalize the concept of Hyperminhash fingerprints in (h,m)-HMH fingerprints that can be tuned to present the lowest false positive rate given the expected sub-sampling applied. Second, we provide a structure able to index any kind of fingerprints based on inverted indexes that provide optimal queries, namely linear with the size of the output. Third, we implemented these approaches in a tool dubbed NIQKI that can index and calculate pairwise distances for over one million bacterial genomes from GenBank in a matter of days on a small cluster. We show that our approach can be orders of magnitude faster than state-of-the-art with comparable precision. We believe that this approach can lead to tremendous improvement allowing fast query, scaling on extensive genomic databases. Availability and implementation: We wrote the NIQKI index as an open-source C++ library under the AGPL3 license available at https://github.com/Malfoy/ NIQKI. It is designed as a user-friendly tool and comes along with usage sample


Author(s):  
Ekaterina Bourova-Flin ◽  
Samira Derakhshan ◽  
Afsaneh Goudarzi ◽  
Tao Wang ◽  
Anne-Laure Vitte ◽  
...  

Abstract Background Large-scale genetic and epigenetic deregulations enable cancer cells to ectopically activate tissue-specific expression programmes. A specifically designed strategy was applied to oral squamous cell carcinomas (OSCC) in order to detect ectopic gene activations and develop a prognostic stratification test. Methods A dedicated original prognosis biomarker discovery approach was implemented using genome-wide transcriptomic data of OSCC, including training and validation cohorts. Abnormal expressions of silent genes were systematically detected, correlated with survival probabilities and evaluated as predictive biomarkers. The resulting stratification test was confirmed in an independent cohort using immunohistochemistry. Results A specific gene expression signature, including a combination of three genes, AREG, CCNA1 and DDX20, was found associated with high-risk OSCC in univariate and multivariate analyses. It was translated into an immunohistochemistry-based test, which successfully stratified patients of our own independent cohort. Discussion The exploration of the whole gene expression profile characterising aggressive OSCC tumours highlights their enhanced proliferative and poorly differentiated intrinsic nature. Experimental targeting of CCNA1 in OSCC cells is associated with a shift of transcriptomic signature towards the less aggressive form of OSCC, suggesting that CCNA1 could be a good target for therapeutic approaches.


1983 ◽  
Vol 38 ◽  
pp. 20-20
Author(s):  
Robert S. Ross

Simulations have been an important adjunct to instructional programs for some time. These have ranged from games, or role playing exercises, such as SIMSOC or Internation Simulation, to student-machine interaction, such as the inter-school simulation run out of University of California, Santa Barbara in the early 70's, to the all machine activities found in some of the early SETUPS. Having social science students use the mainframe computer, however, always posed problems: it definitely was not user-friendly and most instructors had little if any training or interest in the use of large scale systems.The wide-spread use of the micro computer is not only revolutionizing areas traditionally relying upon the computer, but is going to have an impact on the social sciences as well.


2004 ◽  
Vol 31 (7) ◽  
pp. 671 ◽  
Author(s):  
Takayuki Umemoto ◽  
Noriaki Aoki ◽  
Hongxuan Lin ◽  
Yasunori Nakamura ◽  
Naoyoshi Inouchi ◽  
...  

The natural variation in starch synthase IIa (SSIIa) of rice (Oryza sativa L.) was characterised using near-isogenic lines (NILs). SSIIa is a candidate for the alk gene regulating the alkali disintegration of rice grains, since both genes are genetically mapped at the same position on chromosome 6 and related to starch properties. In this study, we report that the alkali-susceptible cultivar Nipponbare lacked SSIIa activity in endosperm. However, the activity was detected with NILs having the alk allele of alkali-tolerant Kasalath. SSIIa protein was present even in Nipponbare endosperm, but it was not associated with starch granules at the milky stage of endosperm. Three single-nucleotide polymorphisms (SNPs) predicting amino acid substitutions existed between the cDNA sequences of SSIIa of Nipponbare and Kasalath were genotyped with 65 rice cultivars and four wild relatives of cultivated rice. The results obtained explain the potential importance of two of the amino acid residues for starch association of rice SSIIa. An analysis of the chain-length distribution of β-limit dextrin of amylopectin showed that without SSIIa activity, the relative number of A-chains (the short chains without branches) increased and that of B1-chains (the short chains with branches) decreased. This suggests that, given the SSIIa defect, short A-chains could not reach a sufficient length for branching enzymes to act on them to produce B1-chains.


2017 ◽  
Vol 33 (13) ◽  
pp. 2020-2028 ◽  
Author(s):  
Oliver Hilsenbeck ◽  
Michael Schwarzfischer ◽  
Dirk Loeffler ◽  
Sotiris Dimopoulos ◽  
Simon Hastreiter ◽  
...  

2018 ◽  
Vol 2 ◽  
pp. 3 ◽  
Author(s):  
Heba Shaaban ◽  
David A. Westfall ◽  
Rawhi Mohammad ◽  
David Danko ◽  
Daniela Bezdan ◽  
...  

The Microbe Directory is a collective research effort to profile and annotate more than 7,500 unique microbial species from the MetaPhlAn2 database that includes bacteria, archaea, viruses, fungi, and protozoa. By collecting and summarizing data on various microbes’ characteristics, the project comprises a database that can be used downstream of large-scale metagenomic taxonomic analyses, allowing one to interpret and explore their taxonomic classifications to have a deeper understanding of the microbial ecosystem they are studying. Such characteristics include, but are not limited to: optimal pH, optimal temperature, Gram stain, biofilm-formation, spore-formation, antimicrobial resistance, and COGEM class risk rating. The database has been manually curated by trained student-researchers from Weill Cornell Medicine and CUNY—Hunter College, and its analysis remains an ongoing effort with open-source capabilities so others can contribute. Available in SQL, JSON, and CSV (i.e. Excel) formats, the Microbe Directory can be queried for the aforementioned parameters by a microorganism’s taxonomy. In addition to the raw database, The Microbe Directory has an online counterpart (https://microbe.directory/) that provides a user-friendly interface for storage, retrieval, and analysis into which other microbial database projects could be incorporated. The Microbe Directory was primarily designed to serve as a resource for researchers conducting metagenomic analyses, but its online web interface should also prove useful to any individual who wishes to learn more about any particular microbe.


2020 ◽  
Author(s):  
Florian Blanc ◽  
Marco Cecchini

The design of molecular architectures exhibiting functional motions is a promising area for disruptive technological development. Towards this goal, rotaxanes and catenanes, which undergo relative motions of their sub-units in response to external stimuli, are prime candidates. Here, we report on the computational analysis of the contraction/extension of a bistable [c2]-daisy chain rotaxane. Using free energy calculations and transition path optimizations, we explore the free energy landscape governing the functional motions of a prototypical molecular machine with atomic resolution.<br>The calculations reveal a sequential mechanism for contraction/extension in which the asynchronous gliding of each ring is preferred over the concerted movement suggested by chemical intuition. Analysis of the underlying free energy surface indicates that dissymmetric gliding is favored because it entails crossings of much smaller barriers.<br>Our findings illustrate an important design principle for molecular machines, namely that efficient exploitation of thermal fluctuations may be realized by breaking down the large-scale functional motions into smaller steps.


Author(s):  
Pankaj Kumar ◽  
Abhay Kumar ◽  
Kamal Sarma ◽  
Paresh Sharma ◽  
Rashmi Rekha Kumari ◽  
...  

Background: A novel, rapid and specific multiplex polymerase chain reaction was developed to diagnose hemo-parasitic infection in bovine blood co-infected with three of the most common hemo-parasites. Methods: The diagnostic process relied on the detection of the three different bovine hemoparasites isolated from red blood cells (RBCs) of cattle (N=30) by conventional Giemsa stained blood smear (GSBS) and confirmed by multiplex PCR. The multiplex PCR system was used to diagnose GSBS positive blood samples (N=12) found infected or co-infected with hemoparasites. The designed multiplex primer sets was attempted to amplify 205, 313 and 422 bp fragments of apocytochrome b, sporozoite and macroschizont 2 (spm2) and 16S rRNA gene for Babesia bigemina, Theileria annulata and Anaplasma marginale, respectively. Result: This multiplex PCR was sensitive with the ability to detect the presence of 150 ng of genomic DNA. The primers used in this multiplex PCR also showed highly specific amplification of specific gene fragments of each respective parasite. Comparing the two detection methods revealed that 58.33% of specimens showed concordant diagnoses with both techniques. The specificity, positive predictive value and kappa coefficient of the agreement was highest for diagnosis of B. bigemina and lowest for A. marginale. The overall Kappa coefficient for diagnosis based on GSBS for multiple pathogens compared to multiplex PCR was 0.56, slightly behind the threshold of 0.6 of agreement. Therefore, confirmation should always be based on PCR to rule out false positives due to differences in subjective observations, stain particles and false negatives due to low parasitemia. The simplicity and rapidity of this specific multiplex PCR method make it suitable for large-scale epidemiological studies and follow-up of drug treatments.


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