A genome enthusiast..

DNA double strand break. Ionising adiation and reactive oxygen...

curiosity-xyz — Thu, 19 Jul 2012 20:43:58 +0100

DNA double strand break.

Ionising adiation and reactive oxygen species such as superoxide, hydroxyl can cause DNA double strand break. When this happens, it can cause severe damage. There are two mechanisms which response to this type of DNA damage.

1. Homologous recombination repair. Uses the undamaged sister chromatid .

2. Non homologous end-joining repair. Requires complex of repair protein.

scinerds: Geneticists Evolve Fruit Flies With the Ability to...

curiosity-xyz — Fri, 13 Jul 2012 08:43:10 +0100

scinerds:

Geneticists Evolve Fruit Flies With the Ability to Count

A team of geneticists has announced that they have successfully bred fruit flies with the capacity to count.

After repeatedly subjecting fruit flies to a stimulus designed to teach numerical skills, the evolutionary geneticists finally hit on a generation of flies that could count — it took 40 tries before the species’ evolution occurred.

The findings, announced at the First Joint Congress on Evolutionary Biology in Canada, could lead to a better understanding of how we process numbers and the genetics behind dyscalculia — a learning disability that affects a person’s ability to count and do basic arithmetic.

“The obvious next step is to see how [the flies’] neuro-architecture has changed,” said geneticist Tristan Long, of Canada’s Wilfrid Laurier University, who admits far more research is needed to delve into what the results actually mean. Primarily, this will involve comparing the genetic make-up of an evolved fruit fly with that of a standard test fly to pinpoint the mutation.

Neuroscience: Genes May Play Role in Educational Achievement

curiosity-xyz — Wed, 04 Jul 2012 09:06:57 +0100

Neuroscience: Genes May Play Role in Educational Achievement: neurosciencestuff: ScienceDaily (July...

ucsdhealthsciences: Beyond Base-Pairs: Mapping the Functional...

curiosity-xyz — Tue, 03 Jul 2012 10:05:44 +0100

ucsdhealthsciences:

Beyond Base-Pairs: Mapping the Functional Genome
Regulatory sequences of mouse genome sequenced for first time

Popularly dubbed “the book of life,” the human genome is extraordinarily difficult to read. But without full knowledge of its grammar and syntax, the genome’s 2.9 billion base-pairs of adenine and thymine, cytosine and guanine provide limited insights into humanity’s underlying genetics.

In a paper published in the July 1, 2012 issue of the journal Nature, researchers at the Ludwig Institute for Cancer Research and the University of California, San Diego School of Medicine open the book further, mapping for the first time a significant portion of the functional sequences of the mouse genome, the most widely used mammalian model organism in biomedical research.

“We’ve known the precise alphabet of the human genome for more than a decade, but not necessarily how those letters make meaningful words, paragraphs or life,” said Bing Ren, PhD, head of the Laboratory of Gene Regulation at the Ludwig Institute for Cancer Research at UC San Diego. “We know, for example, that only one to two percent of the functional genome codes for proteins, but that there are highly conserved regions in the genome outside of protein-coding that affect genes and disease development. It’s clear these regions do something or they would have changed or disappeared.”

Chief among those regions are cis-regulatory elements, key stretches of DNA that appear to regulate the transcription of genes. Misregulation of genes can result in diseases like cancer. Using high-throughput sequencing technologies, Ren and colleagues mapped nearly 300,000 mouse cis-regulatory elements in 19 different types of tissue and cell. The unprecedented work provided a functional annotation of nearly 11 percent of the mouse genome, and more than 70 percent of the conserved, non-coding sequences shared with other mammalian species, including humans.

As expected, the researchers identified different sequences that promote or start gene activity, enhance its activity and define where it occurs in the body during development. More surprising, said Ren, was that the structural organization of the cis-regulatory elements are grouped into discrete clusters corresponding to spatial domains. “It’s a case of form following function,” he said. “It makes sense.”

While the research is fundamentally revealing, Ren noted it is also just a beginning, a partial picture of the functional genome. Additional studies will be needed in other types of cells and at different stages of development.

“We’ve mapped and understand 11 percent of the genome,” said Ren. “There’s still a long way to march.”

sciencephotolibrary: Male Human Sex Chromosomes X and Y (Pair...

curiosity-xyz — Mon, 02 Jul 2012 08:26:00 +0100

sciencephotolibrary:

Male Human Sex Chromosomes X and Y (Pair 23), scanning electron micrograph (SEM). There are 23 pairs of chromosomes in most normal human cells. These are allocated pairs 1 - 22 with pair 23 being the sex chromosomes, either xx for females and xy for males. Magnification x17500 at 10 cm wide.

Credit: POWER AND SYRED/SCIENCE PHOTO LIBRARY

Neuroscience: Rare Genetic Illness May Shed Light on Role of Hormones in Autism, Anxiety

curiosity-xyz — Wed, 27 Jun 2012 09:39:01 +0100

Neuroscience: Rare Genetic Illness May Shed Light on Role of Hormones in Autism, Anxiety:...

scienceyoucanlove: Cancer cell dividingThis was taken by...

curiosity-xyz — Sat, 23 Jun 2012 21:16:53 +0100

scienceyoucanlove:

Cancer cell dividing

This was taken by Kuan-Chung Su at our London Research Institute. It’s actually an image of 27 stills of a cancer cell dividing. Our cells divide millions of times a day – understanding this process is key in our fight against cancer. More info on our blog:http://bit.ly/NTx4oN

Credit: Kuan-Chung Su, London Research Institute, Cancer Research UK
Wellcome Images
images@wellcome.ac.uk
http://images.wellcome.ac.uk/

Transposition of virus and human evolution jtotheizzoe: Viral...

curiosity-xyz — Sat, 23 Jun 2012 10:06:24 +0100

Transposition of virus and human evolution

jtotheizzoe:

Viral Conception

How the origin of mammals could be written in our genome … by viruses.

Every human being starts the same way, with a sperm and egg becoming one, 23 chromosomes from each parent contributing the genetic instructions that will one day make, well … you. But the genes, the actual DNA that writes for proteins, make up only about one one-hundredth of all the DNA in those 46 chromosomes.

A full 8% of the DNA in your genome, though, are the remains of ancient viruses. A certain type of virus called a “retrovirus” is capable of inserting its genome into its host, literally writing itself into your DNA. This is the family that HIV belongs to. If a retrovirus infects an egg and inserts its genome, it can get passed down to the next generation. We are full of these remnants, as inactive but still recognizable fossils of past infections.

Dr. Samuel Pfaff and his team were trying to come up with a list of genes that were turned on in a developing mouse embryo, just after sperm and egg had come together. In its earliest stages, an embryo’s cells can become any tissue (one of the ideas behind stem cell therapies). What genes make this possible?

It turns out that for over 100 genes, the switches (called “promoters”) that turned them on came from a very unlikely place: viruses. WHAT?! We know that these genes must be activated in order for an embryo to correctly develop, but the switches that control them come from ancient viral infections! The genes themselves? Purely mouse.

What an odd paradox of evolution!! We need these genes on at a very precise moment, and off a short while after that. If any of it goes wrong, no baby mouse. So evolution selects these viral sequences to be the control mechanism. Could an ancient infection have been the key to the very existence of mammals?

Carl Zimmer has more at The Loom.

Enzyme Offers New Therapeutic Target for Cancer Drugs

curiosity-xyz — Fri, 22 Jun 2012 10:09:57 +0100

Enzyme Offers New Therapeutic Target for Cancer Drugs: ucsdhealthsciences: Researchers at the...

biocanvas: Three human epithelial cells that have been triple...

curiosity-xyz — Mon, 18 Jun 2012 08:39:21 +0100

biocanvas:

Three human epithelial cells that have been triple stained. DNA is in blue.

Image by Dr. Jennifer Waters, Wake Forest University.

jtotheizzoe: Joe’s Science Buzzkills, Episode “Mosquito...

curiosity-xyz — Mon, 18 Jun 2012 08:37:46 +0100

jtotheizzoe:

Joe’s Science Buzzkills, Episode “Mosquito MAV”

Real or not real?

NOPE NOT REAL.

More after the original post…

lost-and-searching-in-america:

Is this a mosquito? No. It’s an insect spy drone for urban areas, already in production, funded by the US Government. It can be remotely controlled and is equipped with a camera and a microphone. It can land on you, and it may have the potential to take a DNA sample or leave RFID tracking nanotechnology on your skin. It can fly through an open window, or it can attach to your clothing until you take it in your home. Given their propensity to request macro-sized drones for surveillance, one is left with little doubt that police and military may look into these gadgets next.

And for all you who automatically say “fake” because you don’t think your glorious government is funding this… do some research.

Source
Actual research paper
Actual footage
Another source
And another

Here’s a photo going around of a supposed micro aerial vehicle modeled after a mosquito, with various scary Big Brother-esque abilities such as taking DNA samples and installing RFID tags in your skin. It’s completely fake, although it’s a very nifty idea. I don’t mean to ruin your fun. I only bust these lies because I love you.

But the original post says I should do some “research” before declaring it fake, so here’s some more info: Although there are RFID tags smaller than the head of a needle, that’s still be larger than the needle shown in this picture. Also, the “sources” listed are to press releases about a lab that takes high speed videos of butterfly flight, like the one I featured last week, and not referring to any “mosquito spybots”.

The current smallest MAV is a recent DARPA project called The Hummingbird (video included at the link), thus named because it is the size and shape of a hummingbird. There’s lots of “artist’s interpretations” and such, like the one above, but wind instability of these tiny imaginary things that have never been built means that they will remain unbuilt for the near to distant future.

So you and your precious bodily fluids are still safe from tiny robo-insect spy invaders. However, these awesome autonomous bots that play the James Bond theme all by themselves? Totally real, and totally awesome.

jtotheizzoe: Mega DNA Necklace Fancy some biologically...

curiosity-xyz — Wed, 13 Jun 2012 20:07:50 +0100

jtotheizzoe:

Mega DNA Necklace

Fancy some biologically significant jewelry for you or that special someone? How about sporting the double helix in silver, gold and gunmetal?

(via WXYZ JEWELRY)

decaturjim: Deadly genomes: Mapping the size, content, and...

curiosity-xyz — Wed, 13 Jun 2012 09:11:52 +0100

decaturjim:

Deadly genomes: Mapping the size, content, and impact of some of the world’s deadliest infectious agents

See high resolution image here.

contemplatingmadness: Your DNA Changes as You Age While our...

curiosity-xyz — Wed, 13 Jun 2012 09:02:07 +0100

contemplatingmadness:

Your DNA Changes as You Age

While our bodies age, scientists believe that our DNA at least remains constant. New research, however, reveals that, even though its sequence remains constant, subtle chemical changes occur to our DNA as we age—and it could explain why the risk of developing disease increases as we get older.

DNA is made up of four basic chemical building blocks, called adenine, thymine, guanine, and cytosine. It’s the sequences of those chemicals in a strand of DNA that determines what function a gene has, and one of the ways the resulting genes are controlled is a process called methylation. That just means that a methyl group — one carbon atom and three hydrogen atom—bonds to part of the DNA and subtly change its function.

New research, published in PNAS, however, shows that as we grow older our DNA’s susceptibility to methylation changes. A team of researchers from the Bellvitge Biomedical Research Institute in Barcelona, Spain, extracted DNA from white blood cells of twenty newborn babies and twenty people aged between 89 and 100 years old, then compared their respective degrees of methylation.

In a newborn baby 80.5 percent of cytosine nucleotides were methylated, while in centenarians that figure dropped to 73 percent. An intermediary example, taken from a 26-year-old male subject, exhibited 78 percent methylation. It’s not clear why it happens, but the researchers speculate that it could be due to extremely subtle age-related changes to the DNA.

But what the hell does it all mean? Well, taking a closer look at the samples, the researchers discovered that a third of the methylated groups which were in different positions in the elderly compared to the young are already known to be linked to cancer risk.

If you think about the DNA strand as “hardware” and the added methyl groups as “software”—which isn’t actually a bad analogy—you can think of the inappropriately placed methyl groups as software bugs that accumulate with age. It’s just that, for humans, those bugs leads to increased risk of terminal disease. Fortunately, these kinds of findings should help scientists troubleshoot our internal apps. [PNAS via Science]

genannetics: EXTREME GENETICS: Mapping the Genomes of...

curiosity-xyz — Tue, 05 Jun 2012 09:41:12 +0100

genannetics:

EXTREME GENETICS: Mapping the Genomes of Crocodiles and Alligators

Ever think to yourself, “Hey, I wish my model organism was more bite-y…”

Well, meet Dave Ray, professor at Mississippi State University. His team is sequencing the genome of crocodiles and alligators. And do you know what that means? Yup, collecting DNA samples from many, many crocodiles and alligators. Check out Ray and his gang of extreme geneticists as they show us a typical day at the lab.

decaturjim: Three dimensional structure of the Ebola virus The...

curiosity-xyz — Sun, 03 Jun 2012 10:22:05 +0100

decaturjim:

Three dimensional structure of the Ebola virus

The causative agent of viral hemorrhagic fever in humans and a potential biological weapon, Ebola virus is presented here in beautiful, three dimensional form.

The Ebola-encoded structures are shown in maroon, while human cells are shown in grey. This model was based on 20 years of virology data, X-ray analysis, and computation biology techniques.

unravelingtheuniverse: Visualizations (in progressively greater...

curiosity-xyz — Sun, 03 Jun 2012 10:12:24 +0100

unravelingtheuniverse:

Visualizations (in progressively greater detail) that show duplications within the human genome.

holymoleculesbatman: A water drop on a lotus surface showing...

curiosity-xyz — Sun, 03 Jun 2012 10:12:05 +0100

holymoleculesbatman:

A water drop on a lotus surface showing contact angles of approximately 147°.

The lotus effect refers to the very high water repellence (superhydrophobicity) exhibited by the leaves of the lotus flower. Dirt particles are picked up by water droplets due to a complex micro- and nanoscopic architecture of the surface, which minimizes adhesion.

This effect is of a great importance for plants as a protection against pathogens like fungi or algae growth, and also for animals like butterflies, dragonflies and other insects not able to cleanse all their body parts.

Read More

Structure of swine influenza virus showing different type of...

curiosity-xyz — Sun, 03 Jun 2012 10:11:10 +0100

Structure of swine influenza virus showing different type of antigens present on and inside the capsid, including hemagglutnin (HA) and neuraminidase (NA)

the-star-stuff: ALBERT EINSTEIN: The important...

curiosity-xyz — Sun, 03 Jun 2012 10:07:52 +0100

the-star-stuff:

ALBERT EINSTEIN: The important thing

Credit: Gavin Aung Than