Clipmarks | Silkweaver's 'molecular biology' clips

Don't Stress! Bacterial Cell's 'Crisis Command Center' Revealed

Mon, 06 Oct 2008 04:17:22 GMT

clipped by: Silkweaver
clipper's remarks: If a bacteria cell finds itself in a dangerous situation - for example, if the temperature or saltiness of the bacteria's environment reach dangerous levels which threaten the survival of the bacteria -a warning signal from the cell's surface is transmitted into the cell.

Using cutting edge electron microscopy imaging techniques the authors of the new research observed that the stressosomes receive this warning signal, and in response several proteins called RSBT break away from the large stressosome. This breakaway triggers a cascade of signals within the cell which results in over 150 proteins being produced - proteins which enable the cell to adapt, react and survive in its new environment.

Clip Source: www.sciencedaily.com

A bacteria cell's 'crisis command centre' has been observed for the first time swinging into action to protect the cell from external stress and danger, according to new research published in Science.

The research team behind today's study says that finding out exactly how bacteria respond and adapt to stresses and dangers is important because it will further their understanding of the basic survival mechanisms of some of the most resilient, hardy organisms on Earth.

The crisis command centre in certain bacteria cells is a large molecule, dubbed a 'stressosome' by the scientists behind today's research. These cells have around 20 stressosomes floating around inside them, and although scientists knew they played an important role in the cell's response to stressful situations, the complexities of this process had not been fully understood until now.

Tags: molecular biology, bacteriology

MicroRNAs Found In Animals That Appeared A Billion Years Ago

Thu, 02 Oct 2008 18:42:18 GMT

clipped by: Silkweaver

Clip Source: www.sciencedaily.com

MicroRNAs, the tiny molecules that fine-tune gene expression, were first discovered in 1993. But it turns out they've been around for a billion years.

Evidence reported in Nature on October 1

provides a window into the early evolution of these key regulators, placing their origin within the earliest of animal lineages. The research also suggests that microRNAs present early on have undergone extensive changes, which likely have altered their functions across various lineages.

This is the first evidence that microRNAs were present within the earliest animal lineages and are not just characteristic of more complex animals

Remarkably, we discovered their presence within sponge, a member of the earliest diverging group of animals

It appears that both microRNAs and piRNAs have been available to shape gene expression throughout the evolution of animals and perhaps even helped to usher in the era of multicellular animal life," says Bartel.

Tags: microrna, molecular biology, evolution

Molecular Biology - A video

Tue, 30 Sep 2008 17:53:21 GMT

clipped by: Silkweaver

Clip Source: mrbarlow.wordpress.com

Molecular biology is really hard to understand.

For example, in each cell of our body there are 3 billion letters of genetic code in our DNA. This code controls everything our cells do. Particularly, the code contains instructions for making proteins that have different functions around the body.

[Video]

I think visualising this really complex stuff can help you understand it. Fortunately, so does Drew Berry from the Walter and Eliza Hall Institute of Medical Research (WEHI). He runs WEHI TV and creates heaps of molecular animations. Here is an extended clip explaining an awful lot of stuff:

Tags: biology, genetics, science, molecular biology

68 Molecules that hold the key to all Cellular Life

Fri, 05 Sep 2008 01:01:12 GMT

clipped by: Silkweaver
clipper's remarks: Currently, the vast majority of medical research looks to the human genome and proteome for answers, but those answers remain elusive, and perhaps for good reason.

“We have now found instances where the pathogenesis of widespread and chronic diseases can be attributed to a change in the glycome, for example, in the absence of definable changes in the genome or proteome,” Marth said, adding that, as biomedical researchers, “we need to begin to cultivate the integration of disciplines in a holistic and rigorous way in order to perceive and most effectively manipulate the biological mechanisms of health and disease.”

Marth believes that biology should become more integrative both in academic and research settings. “I’m one who believes that we don’t need to sacrifice breadth of knowledge in order to acquire depth of understanding.”

Clip Source: www.physorg.com

Clip Source: www.sciencedaily.com

Why is it that the origins of many serious diseases remain a mystery? In considering that question, a scientist at the University of California, San Diego School of Medicine has come up with a unified molecular view of the indivisible unit of life, the cell, which may provide an answer.

Reviewing findings from multiple disciplines, Jamey Marth, Ph.D., UC San Diego Professor of Cellular and Molecular Medicine and Investigator with the Howard Hughes Medical Institute, realized that only 68 molecular building blocks are used to construct these four fundamental components of cells: the nucleic acids (DNA and RNA), proteins, glycans and lipids.

Like the periodic table of elements, first published in 1869 by Russian chemist Dmitri Mendeleev, is to chemistry, Marth’s visual metaphor offers a new framework for biologists.

These 68 building blocks provide the structural basis for the molecular choreography that constitutes the entire life of a cell

Tags: biology, cell biology

Landmark study opens door to new cancer, aging treatments

Mon, 01 Sep 2008 01:02:41 GMT

clipped by: Silkweaver

Clip Source: www.nature.com

Telomerase protein structure will help research into ageing and cancer.

The part of the enzyme that controls the timing mechanism of cellular ageing has been revealed.

The X-ray crystal structure offers insights into the ageing process of normal cells, and may provide a safer method for treating up to 90% of human cancers.

Clip Source: www.physorg.com

Researchers have attempted for more than a decade to find drugs that shut down telomerase—widely considered the No. 1 target for the development of new cancer treatments—but have been hampered in large part by a lack of knowledge of the enzyme's structure.

In addition to its role in cancer, telomerase holds significant implications for the development of therapies to combat aging and other age-related diseases.

Finding ways to activate telomerase under controlled conditions and allow some cells to begin dividing again could result in healthier, younger-looking tissue that lives longer.

Tags: molecular biology, cancer, anti aging

Researchers turn one form of adult mouse cell directly into another

Wed, 27 Aug 2008 22:18:44 GMT

clipped by: Silkweaver
clipper's remarks: Joan Brugge, Chair of the Department of Cell Biology at Harvard Medical School, said the new study "provides exciting new insights into yet another aspect of cell plasticity that was not appreciated previously and that offers great potential therapeutically. Direct reprogramming represents a more straight-forward strategy to treat diseases involving loss of function of specific cell populations than approaches requiring an intermediate embryonic stem cell," she said.

Clip Source: www.physorg.com

In a feat of biological prestidigitation likely to turn the field of regenerative medicine on its head, Harvard Stem Cell Institute (HSCI) co-director Doug Melton and post doctoral fellow Qiao "Joe" Zhou report having achieved what has long been a dream and ultimate goal of developmental biologists – directly turning one type of fully formed adult cell into another type of adult cell.

The Melton team reports in today's online edition of the journal Nature that, using a technique it is calling "direct reprogramming," the team is able to turn mouse exocrine cells, which make up about 95 percent of the pancreas, into precious and rare insulin-producing beta cells. These beta cells, which comrpise about one percent of the pancreas, are the cells that die off in Type I diabetes.

In addition to its value for the field of regenerative medicine, the work also is a major step forward toward eventually developing a treatment for Type II – and eventually Type I – diabetes

Tags: molecular biology, cell plasticity, regenerative medicine

Future for clean energy lies in 'big bang' of evolution

Tue, 26 Aug 2008 15:45:01 GMT

clipped by: Silkweaver
clipper's remarks: For humans now there is the tantalising possibility of tweaking the photosynthetic reactions of cyanobacteria to produce fuels we want such as hydrogen, alcohols or even hydrocarbons, rather than carbohydrates.
Progress at the research level has been rapid, boosting prospects of harnessing photosynthesis not just for energy but also for manufacturing valuable compounds for the chemical and biotechnology industries. Such research is running on two tracks, one aimed at genetically engineering real plants and cyanobacteria to yield the products we want, and the other to mimic their processes in artificial photosynthetic systems built with human-made components. Both approaches hold great promise and will be pursued in parallel, as was discussed at a recent workshop focusing on the photosynthetic reaction centres of cyanobacteria, organised by the European Science Foundation (ESF).

Clip Source: scienceblogs.com

Clip Source: www.physorg.com

Amid mounting agreement that future clean, "carbon-neutral", energy will rely on efficient conversion of the sun's light energy into fuels and electric power, attention is focusing on one of the most ancient groups of organism, the cyanobacteria.

Dramatic progress has been made over the last decade understanding the fundamental reaction of photosynthesis that evolved in cyanobacteria 3.7 billion years ago, which for the first time used water molecules as a source of electrons to transport energy derived from sunlight, while converting carbon dioxide into oxygen.

The light harvesting systems gave the bacteria their blue ("cyano") colour, and paved the way for plants to evolve by "kidnapping" bacteria to provide their photosynthetic engines, and for animals by liberating oxygen for them to breathe, by splitting water molecules.

Tags: clean energy, molecular biology

The Secret Of Fast Complex Brain Restructuring

Mon, 25 Aug 2008 12:29:42 GMT

clipped by: Silkweaver
clipper's remarks: Up to now, it had been assumed that nerve cells can only exchange information via the synapses which are special contact points. However, synapses require up to two days to become fully functional - a waste of time and energy if the contact is to be broken down again. The brain could take almost 1000 years to develop if a synapse had to mature at each cell contact.

It appears that nerve cells can also obtain information about their neighbours even without a synapse. Neurobiologists Christian Lohmann and Tobias Bonhoeffer from the Max Planck Institute for Neurobiology have now explained how they do that.

The secret to how the information is exchanged: local calcium signals very quickly transmit all the necessary information to the cell. A synapse only actually develops when the cell and the contact point prove to be suitable candidates for long-term contact.

Clip Source: www.physorg.com

Nerve cells constantly create new contact points to their neighbouring cells.

This is how the basic structure of our brain develops. In adults, new contact makes learning and memory possible. However, not all contact between cells is useful - most of it is dismantled again very quickly.

Scientists at the Max Planck Institute for Neurobiology in Martinsried near Munich have now described a completely new technique with which nerve cells can evaluate the quality of the cells they contact in a very time- and energy-saving way.

During brain development, young nerve cells must come into contact with the correct partner cells so that the brain can carry out its complex functions. However, contact between nerve cells is also constantly being set up and dismantled in adults. It is this continuous restructuring of the brain that allows us to learn and to forget.

Tags: neuroscience, molecular biology

Researchers discover technology that silences genes

Mon, 18 Aug 2008 20:01:29 GMT

clipped by: Silkweaver
clipper's remarks: A safe and reliable gene silencing technology might be a component of a larger arsenal of gene therapies. It is a ground breaking research.

Clip Source: www.physorg.com

Mount Sinai researchers have developed a new gene silencing technology that could be used to target genes that can lead to the development of certain diseases.

This technology could pave the way for preventing diseases where gene dysfunction plays a role.

By being able to silence certain genes, we may be able to suppress genes that can cause diseases such as HIV/AIDS, cancer, inflammation and diseases of the central and peripheral nervous systems.

In the study

discovered that Paramecium bursaria chlorella virus uses a viral protein to modify host DNA packing chromatin and switch host transcription machinery for viral replication.

Based on this finding, researchers were able to develop a new gene targeting technology that effectively suppresses transcriptional expression of targeted genes in human cells, including genes that are linked to the onset of a number of diseases.

Tags: gnetics, medicine, molecular biology

Scientists stop the ageing process

Wed, 13 Aug 2008 01:09:53 GMT

clipped by: Silkweaver
clipper's remarks: Interesting results that may one day become the basis of 'age therapies'.

Clip Source: www.abc.net.au

Scientists have stopped the ageing process in an entire organ for the first time, a study released today says.

Published in today's online edition of Nature Medicine, researchers at the Albert Einstein College of Medicine at Yeshiva University in New York City also say the older organs function as well as they did when the host animal was younger.

The researchers, led by Associate Professor Ana Maria Cuervo, blocked the ageing process in mice livers by stopping the build-up of harmful proteins inside the organ's cells.

The researchers say the findings suggest that therapies for boosting protein clearance might help stave off some of the declines in function that accompanies old age.

In experiments, livers in genetically modified mice 22 to 26 months old, the equivalent of octogenarians in human years, cleaned blood as efficiently as those in animals a quarter their age.

Our findings are particularly relevant for neurodegenerative disorders such as Parkinson's and Alzheimer's," she says.

Tags: medicine, aging, molecular biology

Breakthrough In understanding Cancer and other Inflammatory Conditions

Mon, 11 Aug 2008 22:03:45 GMT

clipped by: Silkweaver

Clip Source: www.news.com.au

AUSTRALIAN scientists are hoping to cure leukaemia, asthma and rheumatoid arthritis after their breakthrough discovery of how to stop killer blood cells growing.

The team has unlocked the secrets behind the protein which controls the way the blood cancer cells spread when it is damaged - and have found a way to stop its deadly process.

Work is now starting to design a drug to prevent the damaged proteins operating, effectively stopping the cancer as well as asthma and inflammatory diseases such as rheumatoid arthritis.

The major breakthrough came when the researchers realised the proteins linked together to form networks on the surface of white blood cells after being activated by the hormone, and that by stopping the networks forming they could also stop the growth.

When damaged, the protein's messages cause an over-production of cells or cells which persist too long, resulting in diseases such as leukaemia as well as some inflammatory conditions.

Tags: medicine, molecular biology, cancer

THE ORIGIN OF BIOLOGICAL INFORMATION

Sun, 10 Aug 2008 22:13:40 GMT

clipped by: Silkweaver
clipper's remarks: Yet Muller and Newman insist that population genetics, and thus evolutionary biology, has not identified a specifically causal explanation for the origin of true morphological novelty during the history of life. Central to their concern is what they see as the inadequacy of the variation of genetic traits as a source of new form and structure. They note, following Darwin himself, that the sources of new form and structure must precede the action of natural selection (2003:3)–that selection must act on what already exists. Yet, in their view, the “genocentricity” and “incrementalism” of the neo-Darwinian mechanism has meant that an adequate source of new form and structure has yet to be identified by theoretical biologists. Instead, Muller and Newman see the need to identify epigenetic sources of morphological innovation during the evolution of life. In the meantime, however, they insist neo-Darwinism lacks any “theory of the generative”

Clip Source: www.answertheskeptic.com

In a recent volume of the Vienna Series in a Theoretical Biology (2003), Gerd B. Muller and Stuart Newman argue that what they call the “origination of organismal form” remains an unsolved problem.

In making this claim, Muller and Newman (2003:3-10) distinguish two distinct issues, namely

(1) the causes of form generation in the individual organism during embryological development and

(2) the causes responsible for the production of novel organismal forms in the first place during the history of life.

To distinguish the latter case (phylogeny) from the former (ontogeny), Muller and Newman use the term “origination” to designate the causal processes by which biological form first arose during the evolution of life.

They further argue that we know more about the causes of ontogenesis, due to advances in molecular biology, molecular genetics and developmental biology, than we do about the causes of phylogenesis–the ultimate origination of new biological forms during the remote past.

Tags: theoretical biology, evolution, phylogeny, ontogeny

Viruses can catch colds, says study that redefines life itself

Sun, 10 Aug 2008 22:06:46 GMT

clipped by: Silkweaver
clipper's remarks: Prof La Scola and his colleagues were surprised to spot a smaller type of virus attached to the virus-making factory inside infected cells. The new virus - Sputnik - was unable to infect cells by itself but seemed to hijack the larger to achieve its infectious aims.

By regulating the growth and death of plankton, giant viruses - and satellite viruses such as Sputnik - could be a major influence on ocean nutrient cycles and climate.

"These viruses could be major players in global systems," Nature is told by Prof Curtis Suttle, an expert in marine viruses at the University of British Columbia in Vancouver.

Clip Source: www.dailygalaxy.com

viruses can apparently get sick.

Even better, they're made sick by another virus.

Viruses are the ultimate example of KISS - Keep It Simple Stupid. Nothing but a core of genetic material in a protein shell, they may not be able to do anything but replicate (and even then only with a host cell), but they also outnumber us umpty-billion to one.

Their simplicity also makes them hard to kill

Researchers at the Centre Nationale de la Recherche Scientifique (CNRS) have now discovered a virus, named "Sputnik" for its extreme simplicity, which can hijack the viral factory of another pathogen and insert its own code into the program.

The double-victimised cell now manufactures Sputniks, and copies of the original virus which do manage to be made suffer from damage and imperfections because of this second-super-sub-cellular-sabotage.

Clip Source: www.telegraph.co.uk

the discovery of a giant virus that itself falls ill through infection by another virus seems to suggest they too are alive

Tags: virology, biology, molecular biology

Prevailing theory of aging challenged in Stanford worm study

Sat, 26 Jul 2008 23:07:35 GMT

clipped by: Silkweaver
clipper's remarks: To see whether these signal molecules were part of a wear-and-tear aging mechanism, the researchers exposed worms to stresses thought to cause aging, such as heat (a known stressor for nematode worms), free-radical oxidation, radiation and disease. But none of the stressors affected the genes that make the worms get old.

So it looked as though worm aging wasn’t a storm of chemical damage. Instead, Kim said, key regulatory pathways optimized for youth have drifted off track in older animals. Natural selection can’t fix problems that arise late in the animals’ life spans, so the genetic pathways for aging become entrenched by mistake. Kim’s team refers to this slide as “developmental drift.”

Clip Source: www.thinkgene.com

Age may not be rust after all. Specific genetic instructions drive aging in worms, report researchers at the Stanford University School of Medicine.

Their discovery contradicts the prevailing theory that aging is a buildup of tissue damage akin to rust, and implies science might eventually halt or even reverse the ravages of age.

The question of what causes aging has spawned competing schools of thought.

One side says inborn genetic programs make organisms grow old.

This theory has had trouble gaining traction

The alternate theory holds that aging is an inevitable consequence of accumulated wear and tear

But the Stanford team’s findings told a different story. “Our data just didn’t fit the current model of damage accumulation, and so we had to consider the alternative model of developmental drift

They found hundreds of age-regulated genes switched on and off by a single transcription factor called elt-3, which becomes more abundant with age.

Tags: aging, molecular biology, genetics

Harvard Researchers Create Computer Language That can Penetrate the "Mind" of a Cell

Fri, 25 Jul 2008 13:06:27 GMT

clipped by: Silkweaver
clipper's remarks: This seems to be a milestone in molecular biology and synthetic biology. Using such tools we will be able to better understand molecular biological processes, and perhaps to design novel biological artifacts from scratch.

Clip Source: www.dailygalaxy.com

This language is stepping into an unknown universe, when your computer starts building things for you

Enter into the world of Little b, a computational language developed by a team of Harvard Medical School researchers.

"Through incorporating principles of engineering, we've developed a language that can describe biology in the same way a biologist would,"

The potential here is enormous. This opens the door to actually performing discovery science, to look at things like drug interactions, right on the computer.

Little b, a program written in a programming language called LISP, a language used widely in the field of artificial intelligence research

Gunawardena’s impetus for the creation of Little b is not for something as mediocre as looking in to the human genome, but the human protein.

The protein does much more of the work, and is home to a massive wealth of genomic information far and away past the simple DNA.

Tags: computing, computer languages, molecular biology