BOL: Abhimanyu Singh's News

Caulobacter ethensis - 2.0 : Computer-generated Genome of a Living Organism

Abhimanyu Singh — Wed, 03 Apr 2019 08:45:22 -0500

All the genome sequences of organisms known throughout the world are stored in a database belonging to the National Center for Biotechnology Information in the United States. As of today, the database has an additional entry: Caulobacter ethensis-2.0.

It is the world's first fully computer-generated genome of a living organism, developed by scientists at ETH Zurich.

However, it must be emphasised that although the genome for C. ethensis-2.0 was physically produced in the form of a very large DNA molecule, a corresponding organism does not yet exist.

Source: https://www.sciencedaily.com/releases/2019/04/190401171343.htm

200 point roster restored !

Abhimanyu Singh — Sat, 09 Mar 2019 19:47:35 -0600

The Union Cabinet's decision to restore the 200-point roster system has brought cheer to students and teachers across the country who have relentless protesting for months. The students and teachers also went on a nation wide bandh on March 5 to protest against the new roster system.

The switch from department-wise (13-point and old) reservation to university-wise (200-point) to in faculty positions in universities and colleges is expected to make a big increase in SC/ST and OBC representation among teachers. This is evident from the projection made by the Union government in its review petition filed in the Supreme Court last month. If reservation is implemented university-wise, the total posts across SCs, STs and OBCs in 21 central universities will increase from 1,241 to 2,663.

https://indianexpress.com/article/explained/simply-put-the-unit-in-teachers-quota-5554261/

NgAgo challenge CRISPR !!

Abhimanyu Singh — Tue, 17 May 2016 03:31:32 -0500

A recent Nature Biotechnology paper from Chunyu Han’s lab, DNA-guided genome editing using the Natronobacterium gregoryi Argonaute, is a must-read for genome editing folks who want to learn about NgAgo. Their team sums up NgAgo’s potential pluses this way (emphasis mine):

“The useful features of NgAgo for genome editing include the following.First, it has a low tolerance to guide–target mismatch. A single nucleotide mismatch at each position of the gDNA impaired the cleavage efficiency of NgAgo, and mismatches at three positions completely blocked cleavage in our experiments. Second, 5′ phosphorylated short ssDNAs are rare in mammalian cells, which minimizes the possibility of cellular oligonucleotides misguiding NgAgo.Third, NgAgo follows a ‘one-guide-faithful’ rule, that is, a guide can only be loaded when NgAgo protein is in the process of expression, and, once loaded, NgAgo cannot swap its gDNA with other free ssDNA at 37 °C. All of these features could minimize off-target effects. Finally, it is easy to design and synthesize ssDNAs and to adjust their concentration, which is difficult with the Cas9-sgRNA system, if the sgRNA is expressed from a plasmid and the normal dosage of an ssDNA guide is only ~1/10 of that of a sgRNA expression plasmid.

NgAgo might be a more orderly way and perhaps even simpler way to go about genome editing than CRISPR, but the jury is still out on that until there are more papers and data. The NgAgo edit efficiency at this preliminary stage of technology development seems very strong. See the pics below

Reference: http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.3547.html

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