# gst: apropos of 'normal' (jazzy?) codes, bacteria encode hidden, free-floating genes outside their genome.

AA << show that bacteria break that rule and can create free-floating and ephemeral genes, raising the possibility that similar genes exist outside of our own genome. >>️

<< What this discovery upends is the notion that the chromosome has the complete set of instructions that cells use to produce proteins, (..) We now know that, at least in bacteria, there can be other instructions not preserved in the genome that are nonetheless essential for cell survival. (..) The DNA molecule is a fully functioning, free-floating, transient gene. >> Samuel Sternberg. 

Bacteria Encode Hidden Genes Outside Their Genome—Do We? Columbia University Irving Medical Center. Aug 8, 2024. 

https://www.cuimc.columbia.edu/news/bacteria-encode-hidden-genes-outside-their-genome-do-we   

Stephen Tang, Valentin Conte, et al. De novo gene synthesis by an antiviral reverse transcriptase. Science. doi: 10.1126/ science.adq0876. Aug 8, 2024. 

https://www.science.org/doi/10.1126/science.adq0876

Also: 

codes https://flashontrack.blogspot.com/search?q=codes

DNA  https://flashontrack.blogspot.com/search?q=dna

RNA  https://flashontrack.blogspot.com/search?q=rna

CRISPR  https://flashontrack.blogspot.com/search?q=crispr

normal, jazz, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, codes, dna, rna, crispr, normal, jazz

# life: apropos of transitions, a leap from chemistry to biology, the hypothesis of self-assembling droplets, the 'droplet world'.

AA << identify conditions suitable for concurrent peptide generation and self-assembly, and (..) show how a proliferating peptide-based droplet could be created by using synthesised amino acid thioesters as prebiotic monomers. Oligopeptides generated from the monomers spontaneously formed droplets through liquid–liquid phase separation in water. The droplets underwent a steady growth–division cycle by periodic addition of monomers through autocatalytic self-reproduction. Heterogeneous enrichment of RNA and lipids within droplets enabled RNA to protect the droplet from dissolution by lipids. >>

Matsuo, M., Kurihara, K. Proliferating coacervate droplets as the missing link between chemistry and biology in the origins of life. Nat Commun 12, 5487. doi: 10.1038/ s41467-021-25530-6. Sep 24,  2021.

https://www.nature.com/articles/s41467-021-25530-6

<< By constructing peptide droplets that proliferate with feeding on novel amino acid derivatives, we have experimentally elucidated the long-standing mystery of how prebiotic ancestors were able to proliferate and survive by selectively concentrating prebiotic chemicals, (..) Rather than an RNA world, we found that 'droplet world' may be a more accurate description, as our results suggest that droplets became evolvable molecular aggregates—one of which became our common ancestor. >> Muneyuki Matsuo.

Answering a century-old question on the origins of life. Hiroshima University. Sep 27, 2021. 

https://phys.org/news/2021-09-century-old-life.html

Also

keyword 'drop' | 'droplet' in FonT

https://flashontrack.blogspot.com/search?q=drop

https://flashontrack.blogspot.com/search?q=droplet

keyword 'transition' in FonT

https://flashontrack.blogspot.com/search?q=transition

keyword 'transizione' in Notes (quasi-stochastic poetry): 

https://inkpi.blogspot.com/search?q=transizione

keywords: life, originsoflife, transitions, drop, droplet

# gst: apropos of the structure of natural codes, a RNA folding knot (origami-style) dance

 << Every second, a myriad of shapeless strands of RNA fold, origami-style, into intricate structures inside living cells. Now, for the first time, researchers can watch a data-driven video of this folding as RNA molecules are made by the cellular machinery. >> 

<< as the RNA strand grows, it twists, forming knot-like structures. But as more RNA building blocks are added to the strand, the knots unravel, allowing the molecule’s structure to emerge. >> 

Ground-breaking films show RNA’s complex curves take shape. Experimental data and predictive algorithms combine to reveal the essential biomolecule’s shape-shifting.

Nature. Jan 19, 2021. 

https://www.nature.com/articles/d41586-021-00126-8

AA << model the folding of an RNA called SRP, an ancient RNA found in all kingdoms of life. The molecule is well-known for its signature hairpin shape. When watching the videos, the researchers discovered that the molecule ties itself into a knot and unties itself very quickly. Then it suddenly flips into the correct hairpin-like structure using an elegant folding pathway called toehold mediated strand displacement. >>

<< To the best of our knowledge, this has never been seen in nature, (..) We think the RNA has evolved to untie itself from knots because if knots persist, it can render the RNA nonfunctional. The structure is so essential to life that it had to evolve to find a way to get out of a knot. >> Julius Lucks. 

Amanda Morris. New Videos Show RNA as it's Never Been Seen. First-ever data-driven movies illuminate RNA's mysterious folding process.  McCormick School of Engineering. Jan 15, 2021.

https://www.mccormick.northwestern.edu/news/articles/2021/01/new-videos-show-rna-as-its-never-been-seen.html 

https://youtu.be/2XTi9LG9NnU

Angela M Yu, Paul M. Gasper, et al. Computationally reconstructing cotranscriptional RNA folding from experimental data reveals rearrangement of non-native folding intermediates. Molecular Cell. doi: 10.1016/ j.molcel.2020.12.017

Jan 15, 2021. 

https://www.cell.com/molecular-cell/fulltext/S1097-2765(20)30936-9

# gst: NikS, a small RNA molecule uses a sort of 'bet-hedging' strategy to survive and infect

<< More than half of the world's population carries the bacterium Helicobacter pylori in their stomach mucosa. It often causes no problems throughout life, but sometimes it can cause inflammation, and in some cases, it can even lead to the development of stomach cancer. Helicobacter pylori uses several 'virulence' factors that allow it to survive in the stomach and can lead to the development of disease. (AA) report that multiple of these factors are centrally regulated by a small RNA molecule called NikS.  >>

<< The fact that Helicobacter pylori can colonize such a hostile environment as the stomach so successfully is also due to a special genetic strategy: Like other pathogens, H. pylori uses a strategy known as phase variation to adapt as flexibly as possible to changes in its environment. Phase variation means that the bacteria constantly switch expression of a gene at random through genetic mutations, meaning that some bacteria in a population will always be ready to express the important gene when it becomes important—a sort of 'bet-hedging' strategy. >>

Robert Emmerich. Small RNA as a central player in infections. University of Würzburg. Oct 15, 2020. 

https://phys.org/news/2020-10-small-rna-central-player-infections.html   

Sara K. Eisenbart, Mona Alzheimer, et al. A Repeat-Associated Small RNA Controls the Major Virulence Factors of Helicobacter pylori. Mol Cell. vol 80, issue 2, P210-226.E7. doi: 10.1016/ j.molcel.2020.09.009. Oct 15, 2020. 

https://www.cell.com/molecular-cell/fulltext/S1097-2765(20)30617-1

# evol: iterative hacking mechanics; a large group of viruses can assemble human-virus codes to produce novel chimeric (UFO) proteins

<< Like a scene out of "Invasion of the Body Snatchers," a virus infects a host and converts it into a factory for making more copies of itself. Now researchers have shown that a large group of viruses, including the influenza viruses and other serious pathogens, steal genetic signals from their hosts to expand their own genomes. >>

AA << looked at a large group of viruses known as segmented negative-strand RNA viruses (sNSVs), which include widespread and serious pathogens of humans, domesticated animals and plants, including the influenza viruses and Lassa virus (..) by stealing genetic signals from their hosts, viruses can produce a wealth of previously undetected proteins. The researchers labeled them as UFO (Upstream Frankenstein Open reading frame) proteins, as they are encoded by stitching together the host and viral sequences. There was no knowledge of the existence of these kinds of proteins prior to this study. >>

Viruses can steal our genetic code to create new human-virus genes. The Mount Sinai Hospital. Jun 18, 2020.

https://phys.org/news/2020-06-viruses-genetic-code-human-virus-genes.html

Jessica Sook Yuin Ho, Matthew Angel, et al. Hybrid Gene Origination Creates Human-Virus Chimeric Proteins during Infection. Cell. Vol 181, Issue 7, P1502-1517.e23. doi: 10.1016/ j.cell.2020.05.035. June 25, 2020. 

https://www.cell.com/cell/fulltext/S0092-8674(20)30630-9

# gst: 'transcriptional burst frequency' modulation (more or less noise) during gene regulation

<< In cells, genes are expressed through transcription, a process where genetic information encoded in DNA is copied into messenger RNA (mRNA). The mRNA is then translated to make protein molecules, the workhorses of cells. This entire process is subject to bursts of natural stochasticity—or randomness—which can impact the outcome of biological processes that proteins carry out. >>

<< This work for the first time identifies the role of randomness in altering the outcome of a developmental process.>> Madhav Mani. 

<< By analyzing experimental perturbations of Drosophila's senseless gene against mathematical models, the team determined the sources of the gene's stochasticity, and found that the randomness appears to be leveraged in order to accurately determine sensory neuron fates. >>

<< Let's say you are quickly flipping a light switch on and off, but you want more brightness out of your bulb. You could either get a brighter bulb that produced more photons per unit time, or you could leave the switch 'on' more than 'off,' (..) What we found is that organisms control the amount of gene expression by regulating how often the gene is permitted to switch on, rather than making more mRNAs when it is on. >> Madhav Mani. 

<< From these studies, we are learning rules for how genes can be made more or less noisy, (..) Sometimes cells want to harness the genetic noise—the level of variation in gene expression—to make randomized decisions. Other times cells want to suppress the noise because it makes cells too variable for the good of the organism. Intrinsic features of a gene can imbue them with more or less noise. >> Richard Carthew. 

Alex Gerage. Toward principles of gene regulation in multicellular systems. Northwestern University. Jul 1, 2020.

https://phys.org/news/2020-07-principles-gene-multicellular.html

Rachael Bakker, Madhav Mani, Richard W Carthew. The Wg and Dpp morphogens regulate gene expression by modulating the frequency of transcriptional bursts. eLife. doi: 10.7554/eLife.56076. Jun 22, 2020. 

https://elifesciences.org/articles/56076

# gst: apropos of unexpected Hopfion tangles

<< a certain geometrical structure of knots, which scientists call a Hopfion, manifests itself in unexpected corners of the universe, ranging from particle physics, to biology, to cosmology. >>

<< In a recent theoretical study, (..) (AA) discovered the presence of the Hopfion structure in nano-sized particles of ferroelectrics. >>

<< The Hopfion is a very abstract mathematical concept, (..) but the structure shows up in hydrodynamics, electrodynamics and even in the packing of DNA and RNA molecules in biological systems and viruses. >> Valerii Vinokur

<< When we visualized the polarization, we saw the Hopfion structure emerge, (..) We thought, wow, there is a whole world inside of these nanoparticles. >> Igor Luk'yanchuck.

Savannah Mitchem. Novel insight reveals topological tangle in unexpected corner of the universe. Argonne National Laboratory. May 26, 2020.

https://phys.org/news/2020-05-insight-reveals-topological-tangle-unexpected.html

Luk’yanchuk I., Tikhonov Y., et al. Hopfions emerge in ferroelectrics. 

 Nat Commun 11, 2433. doi: 10.1038/ s41467-020-16258-w. May 15, 2020.

https://www.nature.com/articles/s41467-020-16258-w

# gene: stuttering, syncopated (but not junk) codes

<< All organisms have DNA, the genetic material that provides a blueprint for life. The long double-helix-shaped DNA molecules in the body's cells are first translated into RNA molecules and then translated into proteins that ensure the functioning of the cell and the entire organism. But there are large parts of the DNA that are not used for making proteins. This is called 'junk DNA', because its function remained unclear for a long time. However, a certain type of junk DNA that is found in mosquitoes and which repeats itself dozens of times, known as 'satellite DNA', has now been shown to play an essential role in the early development of mosquito embryos. >>

Stuttering DNA orchestrates the start of the mosquito's life. Radboud University Medical Center. Apr 9, 2020.

https://www.sciencedaily.com/releases/2020/04/200409100332.htm 

AA << results reveal a mechanism by which satellite repeats regulate global gene expression in trans via piRNA-mediated gene silencing that is essential for embryonic development. >>

Rebecca Halbach, Pascal Miesen, et al. A satellite repeat-derived piRNA controls embryonic development of Aedes. Nature 580, 274–277. doi: 10.1038/s41586-020-2159-2. 

Apr 1, 2020.

https://www.nature.com/articles/s41586-020-2159-2

Also

keyword 'piRNA' in ncbi pubmed

"piRNA"[all] AND (Review[ptyp]) AND ("last 3 years"[PDat])

http://www.ncbi.nlm.nih.gov/pubmed

# gst: NS3, how viruses self-cripple their genome replication machinery

<< An interdisciplinary team of researchers (..) has used computational chemistry, biochemistry and virology to uncover new information on how viruses such as West Nile, dengue and Zika replicate. Based on their research, the team said these viruses appear to cripple their own genome replication machinery.  >>

<< Nonstructural Protein 3 - or NS3 - in flaviviruses, (..) cause a number of diseases in humans. NS3 is a key enzyme that these viruses use to copy their genomes. >>

<< Most vaccines are developed by finding random mutations that slow down virus growth, (..) By understanding how viral enzymes like NS3 work in great detail, we can use that information to rationally design new mutant viruses that replicate less well and act better as a vaccine, without having to rely on chance to make the vaccine. This can help develop vaccines more rapidly and precisely. >> Brian Geiss.

New details on how a viral protein puts the brakes on virus replication. Colorado State University.  Feb 7, 2020.

https://m.phys.org/news/2020-02-viral-protein-virus-replication.html

Kelly E. Du Pont, Russell B. Davidson,  et al. Motif V regulates energy transduction between the flavivirus NS3 ATPase and RNA-binding cleft. The Journal of Biological Chemistry 295, 1551-1564. Feb 7, 2020.

http://m.jbc.org/content/295/6/1551

Also

keyword 'NS3 enzyme' in ncbi

https://www.ncbi.nlm.nih.gov/m/pubmed/?term=NS3+enzyme

# evol: the origins of life on earth could be arisen from the same set of DNA and RNA precursor molecules

<< the first living things on Earth may have used both RNA (ribonucleic acid) and DNA (deoxyribonucleic acid), as all cell-based life forms do now. In contrast, the prevailing scientific view—the "RNA World" hypothesis—is that early life forms were based purely on RNA, and only later evolved to make and use DNA. >>

<< These new findings suggest that it may not be reasonable for chemists to be so heavily guided by the RNA World hypothesis in investigating the origins of life on Earth, >>

Ramanarayanan Krishnamurthy. Building blocks of DNA and RNA could have appeared together before life began on Earth. The Scripps Research Institute. April 1, 2019.

https://m.phys.org/news/2019-04-blocks-dna-rna-life-began.html  

Jianfeng Xu, Nicholas J. Green, et al. Prebiotic phosphorylation of 2-thiouridine provides either nucleotides or DNA building blocks via photoreduction. Nature Chemistry. doi: 10.1038/s41557-019-0225-x April 1, 2019.

https://www.nature.com/articles/s41557-019-0225-x

# evol: nonlinear effects in shaping human evolution, the role of viruses

<< Human evolution used to be depicted as a straight line, gradually progressing from an ape-like ancestor to modern Homo sapiens. But thanks to next-generation sequencing, findings in recent years have shown that it wasn’t quite so orderly. Now, a new study is reporting new details about the role of viruses in shaping evolution, in particular, viral interactions between modern humans and Neanderthals. >>

<< Many Neanderthal sequences have been lost in modern humans, but some stayed and appear to have quickly increased to high frequencies at the time of contact, suggestive of their selective benefits at that time, >> Dmitri Petrov

New study reports the role of viruses in shaping evolution. Oct 5, 2018.

https://thesurg.com/virus-shaping-evolution

AA << hypothesized that interbreeding between Neanderthals and modern humans led to (1) the exposure of each species to novel viruses and (2) the exchange of adaptive alleles that provided resistance against these viruses. >>

David Enard, Dmitri A. Petrov. Evidence that RNA Viruses Drove Adaptive Introgression between Neanderthals and Modern Humans. Cell. 175 (2) P360-371.E13 Oct 4, 2018.

https://www.cell.com/cell/fulltext/S0092-8674(18)31095-X 

# drugs: spray with autocatalyic effects: an inhalable form of Messenger RNA

<< Messenger RNA encodes genetic instructions that stimulate cells to produce specific proteins. >>

<< In an advance that could lead to new treatments for lung disease, MIT researchers have now designed an inhalable form of mRNA. This aerosol could be administered directly to the lungs to help treat diseases such as cystic fibrosis >>

Engineers create an inhalable form of messenger RNA. Massachusetts Institute of Technology (MIT).  Jan 4, 2019.

https://m.phys.org/news/2019-01-inhalable-messenger-rna.html

Asha Kumari Patel, James C. Kaczmarek, et al. Inhaled Nanoformulated mRNA Polyplexes for Protein Production in Lung Epithelium. Advanced Materials Jan 4, 2019 doi: 10.1002/adma.201805116

https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.201805116

# evol: life as a product of molecular self-assembly

<< There are currently two main schools of thought regarding the origins of RNA. In one school, RNA is considered to be a product of nonenzymatic, prebiotic reactions. In the other, RNA is considered to be a product of chemical and/or biological evolution. >>

AA << report progress toward finding a proto-RNA that is the product of molecular self-assembly. >>

Cafferty B.J., Fialho D.M., Hud N.V. (2018) Searching for Possible Ancestors of RNA: The Self-Assembly Hypothesis for the Origin of Proto-RNA. In: Menor-Salvan C. (eds) Prebiotic Chemistry and Chemical Evolution of Nucleic Acids. Nucleic Acids and Molecular Biology, vol 35. Springer, Cham. doi: 10.1007/978-3-319-93584-3_5

https://link.springer.com/chapter/10.1007%2F978-3-319-93584-3_5

Joelle Renstrom. New study identifies possible ancestors of RNA. Astrobiol  Mag. Sep 17, 2018.

https://m.phys.org/news/2018-09-ancestors-rna.html 

# gene: point code cracking machines (without detectable byproducts)

DNA cracking machine

<< The spontaneous deamination of cytosine is a major source of C•G to T•A transitions, which account for half of known human pathogenic point mutations. The ability to efficiently convert target A•T base pairs to G•C could therefore advance the study and treatment of genetic diseases >>

AA << report adenine base editors (ABEs) that mediate conversion of A•T to G•C in genomic DNA >>

<< ABEs advance genome editing by enabling the direct, programmable introduction of all four transition mutations without double-stranded DNA cleavage >>

Nicole M. Gaudelli, Alexis C. Komor, et al. Programmable base editing of A•T to G•C in genomic DNA without DNA cleavage. Nature 2017 doi: 10.1038/nature24644 Oct 25, 2017
   
https://www.nature.com/nature/journal/vaap/ncurrent/full/nature24644.html

<< there are virtually no detectable byproducts such as random insertions, deletions, translocations, or other base-to-base conversions >>

Researchers extend power of gene editing by developing a new class of DNA base editors. Oct 25, 2017

https://m.phys.org/news/2017-10-enzyme-rewrites-genome.html

RNA cracking machine

<< RNA Editing for Programmable A to I Replacement (REPAIR), which has no strict sequence constraints, can be used to edit full-length transcripts containing pathogenic mutations >>

David B. T. Cox, Jonathan S. Gootenberg, et al. RNA editing with CRISPR-Cas13. Science. Oct 25, 2017:eaaq0180 doi: 10.1126/science.aaq0180

http://science.sciencemag.org/content/early/2017/10/24/science.aaq0180

Researchers engineer CRISPR to edit single RNA letters in human cells. Oct 25, 2017

https://m.phys.org/news/2017-10-crispr-rna-letters-human-cells.html

Lauran Neergaard. Scientists working toward reversible kind of gene editing. Oct. 25, 2017

https://m.phys.org/news/2017-10-scientists-reversible-kind-gene.html

also:

http://flashontrack.blogspot.it/search?q=crispr

# s-phyto: mRNA instability may facilitate rapid recovery of plants after stressful events

<< Stress recovery may prove to be a promising approach to increase plant performance, and theoretically, mRNA instability may facilitate faster recovery.   Transcriptome (RNA-seq, qPCR, sRNA-seq, PARE) and methylome profiling during repeated excess-light stress and recovery was performed at intervals as short as three minutes >>

AA << demonstrate that 87% of the stress-upregulated mRNAs analysed exhibit very rapid recovery >>

Peter Alexander Crisp, Diep Ganguly, et al.  Rapid recovery gene downregulation during excess-light stress and recovery in Arabidopsis. The Plant Cell Publ. July 2017 doi: 10.1105/tpc.16.00828

http://www.plantcell.org/content/early/2017/07/13/tpc.16.00828

# s-gene: a CRISPR-based RNA-targeting approach, the begin ...

<< a  new  CRISPR  system,  (..)  targets  RNA  rather  than  DNA (..), has  the  potential  to  open  a  powerful  avenue  in  cellular  manipulation. Whereas  DNA  editing  makes  permanent  changes  to  the  genome  of  a  cell,  the  CRISPR-based RNA-targeting  approach  may  allow  researchers  to  make  temporary  changes  that  can  be adjusted  up  or  down,  and  with  greater  specificity  and  functionality  than  existing  methods  for RNA  interference >>

Researchers  unlock  new  CRISPR  system  for targeting  RNA. June  2,  2016.

http://m.phys.org/news/2016-06-crispr-rna.html

Omar O. Abudayyeh,  Jonathan  S.  Gootenberg,  et al. C2c2 is a single-component  programmable  RNA-guided  RNA-targeting  CRISPR  effector. Science    02  Jun 2016: DOI:  10.1126/science.aaf5573

http://science.sciencemag.org/content/early/2016/06/01/science.aaf5573

# s-evol: short messages in speciation

<< changes  in  the  sequence  and  length  of  four  microRNAs [post-transcriptional  gene  regulators] may  be  specific to  humans.  Two  were  highly  expressed  in  brain  tissue  and  may  exert  effects  on  genes  with neural  functions, while  two  exhibit  restricted  expression  patterns  that  the  authors  posited  implied a  role  in  development.  The  authors  also  found  that  "age"  might  matter;  in  an  evolutionary  sense, "younger"  microRNAs  had  less  sequence  conservation,  expression  and  disease  association, and  were  more  isolated  than  "older"  microRNAs. >>

Specific  changes  to  non-coding  RNA  may  be  part of  what  makes  us  human. May  9,  2016

http://m.phys.org/news/2016-05-specific-non-coding-rna-human.html

<< microRNAs  are  crucial  post-transcriptional  regulators  of  gene  expression  involved  in  a  wide  range  of  biological  processes. Although  microRNAs  are  highly  conserved  among  species,  the  functional  implications  of  existing  lineage-specific  changes  and their  role  in  determining  differences  between  humans  and  other  great  apes  have  not  been  specifically  addressed.  We  analyzed  the recent  evolutionary  history  of  1,595  human  microRNAs  by  looking  at  their  intra-  and  inter-species  variation  in  great  apes  using high-coverage  sequenced  genomes  of  82  individuals  including  gorillas,  orangutans,  bonobos,  chimpanzees  and  humans. >>

Gallego  A,  Melé  M,  et al. (2016)  Functional Implications  of  Human-Specific  Changes  in  Great  Ape  microRNAs.  PLoS  ONE  11(4):  e0154194. doi:10.1371/journal.pone.0154194

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0154194

# s-gene: shorter than 18 nt

<< (..) current approaches underestimate reproducibly detected RNAs that are shorter than 18 nt [ units of nucleotides ] and theoretical considerations suggest that such shorter RNAs could be used for sequence-specific gene regulation in organisms like C. elegans that have small genomes >>

Blumenfeld AL, et al. Reproducible features of small RNAs in C. elegans reveal NU RNAs and provide insights into 22G RNAs and 26G RNAs. RNA. 2015.

http://www.ncbi.nlm.nih.gov/m/pubmed/26647462/

poeticamente, si potrebbe anche azzardare:  << piu' piccolo e' il messaggio, piu' alta sara' la cuspide dell'onda generata ... >> Anonymous, XX e.V.

# s-gene-lab: mammalian genome editing new tech: CRISPR-Cpf1

<< A team including the scientist who first harnessed CRISPR-Cas9 system for mammalian genome editing has now identified a different CRISPR system (CRISPR-Cpf1) with the potential for even simpler and more precise genome engineering >>

http://www.sciencedaily.com/releases/2015/09/150925131512.htm

Zetsche et al. Cpf1 Is a Single RNA-Guided Endonuclease of a Class 2 CRISPR-Cas System. Cell, September 2015 DOI: 10.1016/j.cell.2015.09.038

http://www.cell.com/abstract/S0092-8674%2815%2901200-3

<< The Zhang lab offers free online tools and resources for researchers through its website >>

 http://www.genome-engineering.org