BOL: Related items

String graph based genome assembly software and tools !

Rahul Nayak — Tue, 19 Dec 2017 17:17:38 -0600

In graph theory, a string graph is an intersection graph of curves in the plane; each curve is called a "string". String graphs were first proposed by E. W. Myers in a 2005 publication. In recent Genome Research paper describing an innovative approach for assembling large genomes from NGS data caught our attention for several reasons. i) it give different "string graph" prospective of long lasting genome assembly problem ii) the paper is coauthored by Jared Simpson, the developer of ABySS assembler and Richard Durbin. iii) Simpson-Durbin algorithm is that it does not rely on de Bruijn graphs, and instead employs a different graph construction approach called ‘string graph’.

Following are the genome assembly tools based on string graph:

1.SGA (String Graph Assembler) https://github.com/jts/sga

Assembles large genomes from high coverage short read data. SGA is designed as a modular set of programs, which are used to form an assembly pipeline. SGA implements a set of assembly algorithms based on the FM-index. As the FM-index is a compressed data structure, the algorithms are very memory efficient. The SGA assembly has three distinct phases. The first phase corrects base calling errors in the reads. The second phase assembles contigs from the corrected reads. The third phase uses paired end and/or mate pair data to build scaffolds from the contigs. The output of this software is a PDF report that allows the properties of the genome and data quality to be visually explored. By providing more information to the user at the start of an assembly project, this software will help increase awareness of the factors that make a given assembly easy or difficult, assist in the selection of software and parameters and help to troubleshoot an assembly if it runs into problems.

2. SAGE: String-overlap Assembly of GEnomes https://github.com/lucian-ilie/SAGE2

SAGE, for de novo genome assembly. As opposed to most assemblers, which are de Bruijn graph based, SAGE uses the string-overlap graph. SAGE builds upon great existing work on string-overlap graph and maximum likelihood assembly, bringing an important number of new ideas, such as the efficient computation of the transitive reduction of the string overlap graph, the use of (generalized) edge multiplicity statistics for more accurate estimation of read copy counts, and the improved use of mate pairs and min-cost flow for supporting edge merging. The assemblies produced by SAGE for several short and medium-size genomes compared favourably with those of existing leading assemblers.

3. FSG: Fast String Graph

The new integrated assembler has been assessed on a standard benchmark, showing that fast string graph (FSG) is significantly faster than SGA while maintaining a moderate use of main memory, and showing practical advantages in running FSG on multiple threads. Moreover, we have studied the effect of coverage rates on the running times.

4. BASE https://github.com/dhlbh/BASE

It enhances the classic seed-extension approach by indexing the reads efficiently to generate adaptive seeds that have high probability to appear uniquely in the genome. Such seeds form the basis for BASE to build extension trees and then to use reverse validation to remove the branches based on read coverage and paired-end information, resulting in high-quality consensus sequences of reads sharing the seeds. Such consensus sequences are then extended to contigs. BASE is a practically efficient tool for constructing contig, with significant improvement in quality for long NGS reads. It is relatively easy to extend BASE to include scaffolding.

5. Fermi https://github.com/lh3/fermi/

Fermi is a de novo assembler with a particular focus on assembling Illumina short sequence reads from a mammal-sized genome. In addition to the role of a typical assembler, fermi also aims to preserve heterozygotes which are often collapsed by other assemblers. Its ultimate goal is to find a minimal set of unitigs to represent all the information in raw reads.

If you want to learn about String Graph assembler, please read the following papers -

i) The Fragment Assembly String Graph - E. W. Myers

This paper describes the String Graph concept.

ii) Efficient construction of an assembly string graph using the FM-index - Jared T. Simpson and Richard Durbin

This earlier paper from Simpson and Durbin

iii) Efficient de novo assembly of large genomes using compressed data structures - Jared T. Simpson and Richard Durbin

A comprehensive atlas of human gene activity released !!!

Abhimanyu Singh — Tue, 02 Sep 2014 14:20:24 -0500

A large international consortium of researchers has produced the first comprehensive, detailed map of the way genes work across the major cells and tissues of the human body. The findings describe the complex networks that govern gene activity, and the new information could play a crucial role in identifying the genes involved with disease.

We are able to pinpoint the regions of the genome that can be active in a disease and in normal activity, whether it’s in a brain cell, the skin, in blood stem cells or in hair follicles. This is a major advance that will greatly increase our ability to understand the causes of disease across the body.

The research is outlined in a series of papers published March 27, 2014, two in the journal Nature and 16 in other scholarly journals. The work is the result of years of concerted effort among 250 experts from more than 20 countries as part of FANTOM 5 (Functional Annotation of the Mammalian Genome). The FANTOM project, led by the Japanese institution RIKEN, is aimed at building a complete library of human genes.

Researchers studied human and mouse cells using a new technology called Cap Analysis of Gene Expression (CAGE), developed at RIKEN, to discover how 95% of all human genes are switched on and off. These “switches” — called “promoters” and “enhancers” — are the regions of DNA that manage gene activity. The researchers mapped the activity of 180,000 promoters and 44,000 enhancers across a wide range of human cell types and tissues and, in most cases, found they were linked with specific cell types.

Referene : www.kurzweilai.net/first-comprehensive-atlas-of-human-gene-activity-released

RAVEN: a software suite for Matlab that allows for semi-automated reconstruction of genome-scale models

Jit — Wed, 24 Oct 2018 22:38:05 -0500

The RAVEN (Reconstruction, Analysis and Visualization of Metabolic Networks) Toolbox 2 is a software suite for Matlab that allows for semi-automated reconstruction of genome-scale models (GEMs). It makes use of published models and/or KEGG, MetaCyc databases, coupled with extensive gap-filling and quality control features. The software suite also contains methods for visualizing simulation results and omics data, as well as a range of methods for performing simulations and analyzing the results. The software is a useful tool for system-wide data analysis in a metabolic context and for streamlined reconstruction of metabolic networks based on protein homology.

Address of the bookmark: https://github.com/SysBioChalmers/RAVEN

Which of the following programming language is best for a bioinformatics beginner?

Manisha Mishra — Thu, 04 Sep 2014 07:51:16 -0500

I will be doing NGS in the course of my research work and I will like to learn a programming language which is compatible with most bioinformatics tools or software. I basically want to do de-novo assembly, map reads, align reads, and expression analysis. Recommendations welcomed. Which languages would you recommend to a student wishing to enter the world of bioinformatics?

Research Scientist – Bioinformatics at Sidra Medical and Research Center

Wed, 10 Sep 2014 14:35:35 -0500

Sidra Medical and Research Center(Doha, Qatar) is looking for talented Research Scientists (Bioinformatics / NGS Data Analysis).

Research Scientists within the Bioinformatics Program are involved in research related to cutting edge genomics and analysis of omics data. The research will utilize concepts, theories and best practices obtained from bioinformatics discipline and applied to biological and other biomedical data for analysis. The role may also involve designing databases, algorithm and/or computation methods for analyzing genomics and other omics data. The scientist will be working closely with the Translational Medicine Program within a state-of-the art research setting.

Please check the details of the opening and apply here: http://careers.sidra.org/sidra/Vacan...acancyID=60181

Juicebox: Visualization and analysis software for Hi-C data

Jit — Fri, 21 Feb 2020 00:33:38 -0600

Juicebox is visualization software for Hi-C data. This distribution includes the source code for Juicebox, Juicer Tools, and Assembly Tools. Download Juicebox here, or use Juicebox on the web. Detailed documentation is available on the wiki. Instructions below pertain primarily to usage of command line tools and the Juicebox jar files.

Juicebox can now be used to visualize and interactively (re)assemble genomes. Check out the Juicebox Assembly Tools Module website https://aidenlab.org/assembly for more details on how to use Juicebox for assembly.

GUI at https://aidenlab.org/juicebox/

Address of the bookmark: https://github.com/aidenlab/Juicebox

INTERNSHIP @ NIPGR

Sat, 13 Sep 2014 16:02:35 -0500

Applications are invited from suitable candidates for six months ‘Training Fellowship' at National Institute of Plant Genome Research (NIPGR).

About National Institute Of Plant Genome Research (NIPGR) http://www.nipgr.res.in/

The National Institute of Plant Genome Research is an autonomous institution supported by the Department of Biotechnology, Government of India. It is committed to make the institute a premier Institution for plant genomic research in the country. It was established to contribute in the achievement of such hopes as a part of national effort for meeting the challenges in the midst of fast pace of international genomic research and grasping of opportunities on long-term basis.

About the Internship:

The selected intern(s) will work in the area of in Bioinformatics under the BTISNET program of DBT in the Distributed Information Sub center (DISC) facility at NIPGR, New Delhi, under the supervision of Dr. Gitanjali Yadav, Scientist, NIPGR.

Who can apply:

Students currently pursuing the final year of Masters Degree (or equivalent) in Bioinformatics/Biotechnology with strong interest in Computational Biology and First class/division throughout academic career may apply.

Java utilities for Next Generation Sequencing by Pierre Lindenbaum

Robert M Willioms — Mon, 15 Sep 2014 17:24:49 -0500

Java utilities for Bioinformatics

https://github.com/lindenb/jvarkit

Address of the bookmark: https://github.com/lindenb/jvarkit

GEnView: A phylogeny based comparative genomics software to analyze the genetic environment of genes

Abhi — Tue, 28 Dec 2021 01:49:03 -0600

A phylogeny based comparative genomics software to analyze the genetic environment of genes. The user can select one or several taxa and provide one or several reference protein(s). Genomes and plasmids (based on user choice) will be downloaded from the NCBI Assembly/NR database and searched for the respective gene. Alternatively, custom genomes can be provided. User selected stretches (20kbp by default) of the genes genetic environment are extracted, annotated and aligned between all genomes. The sequences are then visualized, enabling comparison of synteny and gene content.

More at https://pubmed.ncbi.nlm.nih.gov/34951622/

Address of the bookmark: https://github.com/EbmeyerSt/GEnView

KAU Thrissur Biotech/Bioinformatics RA/SRF/JRF/Trainee/Studentships

Fri, 26 Sep 2014 20:07:28 -0500

Applications are invited from eligible candidates for the following posts at Bioinformatics Centre (DIC), IT- BT Complex, College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur.

1. Research Associate
Emoluments*: 14880/- + HRA
Qualification needed: Ph.D/M.Sc in Bioinformatics or Ph.D/M.Sc in Agriculture or Biotechnology with advanced Diploma in Bioinformatics
Desirable: 2 year experience in Bioinformatics.

2 Senior Research Fellow
Emoluments*: 10230/-
Qualification needed: M.Sc/ M.tech in Bioinformatics or M.Sc in Agriculture/ Biotechnology with Diploma in Bioinformatics.
Desirable: One year experience in Bioinformatics

3 Junior Research Fellow
Emoluments*: 9300/-
Qualification needed: M.Sc/ M.tech in Bioinformatics or M.Sc in Agriculture/Biotechnology/Plant Sciences with Diploma in Bioinformatics.

4 .Trainee/Studentship Bioinformatics
Emoluments*: 5000/-
Qualification needed: M.Sc in Bioinformatics with good knowledge of Bioinformatics softwares and tools.

5 Trainee/ Studentship Biotechnology
Emoluments*: 5000/-
Qualification needed: M.Sc in Biotechnology, with working knowledge in tissue culture, molecular markers and cloning of genes.

Candidates with the required qualifications and experience may give an application in the prescribed format with attested copies of certificates to prove eligibility on or before 30th November 2014. The applications are to be addressed to The Associate Dean, College of Horticulture and send to "Professor & Coordinator, Bioinformatics Centre (DIC), IT-BT Complex, Kerala Agricultural University, Vellanikkara, Thrissur, Kerala 680 656”. The envelope may be superscribed “Application for the post at Bioinformatics Centre”.

*Emoluments are likely to be revised in 2014-2015

More at http://www.kaubic.in/downloads/Notification_bic.pdf
http://www.kaubic.in/downloads/Application%20form.pdf