Molecular & Cell Biology

Category: Molecular & Cell Biology

New research from the Monell Center reveals that tumor necrosis factor (TNF), an immune system regulatory protein that promotes inflammation, also helps regulate sensitivity to bitter taste. The finding may provide a mechanism to explain the taste system abnormalities and decreased food intake that can be associated with infections, autoimmune disorders, and chronic inflammatory diseases.

Genes usually always be expressed as in Western writing: from left to right on the white canvas of our DNA. So when we speak of the activity of our genome, in fact we are referring to the expression of genes in this sense of the double-stranded DNA.


Nerve cells have different shapes: while the cell body (red) is found in a central position in rats, it is located at the end of a cell prolongation in flies.
Nerve cells come in very different shapes. Researchers at the Bernstein Center Berlin now reveal why, in insects, the cell body is usually located at the end of a separate extension. Using mathematical models, they show that this increases the strength of electrical signal transmission at no additional energetic cost.

In results presented today at the American Association for Cancer Research (AACR) Annual Meeting 2015, a collaborative study by the University of Colorado Cancer Center and the National Cancer Institute (NCI) reports that the TERT gene promoter was altered in 69 percent of 54 cases of bladder cancer due to variants that occur after birth (called "somatic") and in 56 percent of bladder cancers due to inherited variants (called "germline"). The study shows these TERT alterations frequently co-occur with alterations in recently identified bladder cancer genes such as the stromal antigen 2 (STAG2), and the lysine-specific demethylase 6A (KDM6A).

Researchers from the University of Birmingham have identified an important new way in which our immune systems are regulated, and hope that understanding it will help tackle the debilitating effects of type 1 diabetes, rheumatoid arthritis and other serious diseases.

An international team of researchers at German Center for Neurodegenerative Diseases (DZNE) and Tokyo Institute of Technology (Tokyo Tech) have revealed in a collaborative study - published today in NEURON, that neurons in the eye change on the molecular level when they are exposed to prolonged light. The researchers could identify that a feedback signalling mechanism is responsible for these changes. The innate neuronal property might be utilized to protect neurons from degeneration or cell death in the future.

Scientists have discovered a protein that plays a central role in promoting immunity to viruses and cancer, opening the door to new therapies.

New work by Ludwig-Maximilians-Universitaet (LMU) in Munich researchers demonstrates that macrophages can effectively substitute for so-called dendritic cells as primers of T-cell-dependent immune responses. Indeed, they stimulate a broader-based response.

Researchers from North Carolina State University and the University of Colorado, Boulder, have developed a statistical model that allows them to tell where a dust sample came from within the continental United States based on the DNA of fungi found in the sample.


Correct tight junctions between cells labeled in yellow due to the presence of the protein PARD3.
Researchers at Genes and Cancer group at Bellvitge Biomedical Research Institute (IDIBELL), led by Montse Sanchez-Cespedes, have identified the PARD3 gene as a tumor suppressor that is inactivated in lung cancer squamous type. The results of the study have been published in Cancer Research.

KU Leuven researchers have zeroed in on what makes cancer cells in melanoma so aggressive. They also succeeded in taming the effect in cell cultures. Melanoma, a type of skin cancer, is notoriously quick to metastasize and responds poorly to existing cancer treatments. In their study, published in Nature Communications, the researchers report a significant step forward in the characterization and potential treatment of melanoma.

A clearer understanding of the origin recognition complex (ORC) - a protein complex that directs DNA replication - through its crystal structure offers new insight into fundamental mechanisms of DNA replication initiation. This will also provide insight into how ORC may be compromised in a subset of patients with Meier-Gorlin syndrome, a form of dwarfism in humans.

For the first time, a research team, led by a UC San Francisco biologist, has isolated energy-burning "beige" fat from adult humans, which is known to be able to convert unhealthy white fat into healthy brown fat. The scientists also found new genetic markers of this beige fat.

Researchers have been fascinated for a long time by learning and memory formation, and many questions are still open. Bochum-based neuroscientists Prof Dr Denise Manahan-Vaughan and Dr Hardy Hagena have discovered a key building block for this complex process. A particular neurotransmitter receptor, namely the metabotropic glutamate receptor 5, is a switch for activating opposing forms of plasticity in the hippocampus, a brain region vital for memory forming. They reported in the current edition of "The Journal of Neuroscience".

Scientists have revealed a brand new function for one of the first cancer genes ever discovered - the retinoblastoma gene - in a finding that could open up exciting new approaches to treatment.

New research shows bacteria can use tiny magnetic particles to effectively create a 'natural battery.' According to work published in journal Science on 27 March, the bacteria can load electrons onto and discharge electrons from microscopic particles of magnetite. This discovery holds out the potential of using this mechanism to help clean up environmental pollution, and other bioengineering applications. The European Association of Geochemistry is highlighting this work as especially interesting.

Researchers at the University of California, San Diego School of Medicine have discovered a control switch for the unfolded protein response (UPR), a cellular stress relief mechanism drawing major scientific interest because of its role in cancer, diabetes, inflammatory disorders and several neural degenerative disorders, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS), otherwise known as Lou Gehrig's disease.


Figure 1 shows hydrogel-aptamer capture and release. The hydrogel can be made sensitive to environmental variables. In the current study, changes in solution pH cause the hydrogel to either swell... Like vast international trading companies, biological systems pick up freight items (in the form of small molecules), transport them from place to place and release them at their proper destination. These ubiquitous processes are critical for activities ranging from photosynthesis to neuronal signaling.


All the neurons within this microscopic roundworm are highlighted, with the large cluster at one end representing the brain.
Even worms have free will. If offered a delicious smell, for example, a roundworm will usually stop its wandering to investigate the source, but sometimes it won't. Just as with humans, the same stimulus does not always provoke the same response, even from the same individual. New research at Rockefeller University, published online today (March 12) in Cell, offers a new neurological explanation for this variability, derived by studying a simple three-cell network within the roundworm brain.

McGill researchers have discovered, for the first time, the importance of a key epigenetic regulator in the development of the hippocampus, a part of the brain associated with learning, memory and neural stem cells. Epigenetic regulators change the way specific genes function without altering their DNA sequence. By working with mutant mice as models, the research team, led by Prof. Xiang-Jiao Yang, of McGill's Goodman Cancer Center & Department of Medicine, McGill University Health Center, was able to link the importance of a specific epigenetic regulator known as BRPF1 to the healthy development of a region in the hippocampus called the dentate gyrus.

Scientists at the USC Leonard Davis School of Gerontology have discovered a new hormone that fights the weight gain caused by a high-fat Western diet and normalizes the metabolism - effects commonly associated with exercising.

Cold Spring Harbor, NY - It sounds like the stuff of science fiction: researchers slice a brain into thin little sections and, just by measuring the properties of specific neurons, they can determine what an organism learned before it died. In fact, this sort of mind reading has become a reality. In work published today in Nature, researchers at Cold Spring Harbor Laboratory (CSHL) describe how postmortem brain slices can be "read" to determine how a rat was trained to behave in response to specific sounds. The work provides one of the first examples of how specific changes in the activity of individual neurons encode particular acts of learning and memory in the brain.

U.S. and Australian scientists have found the mechanism a novel gene uses to affect brain function and elicit behavior related to neuropsychiatric disease.


Jens Hjerling-Leffler and Sten Linnarsson are principal investigators at the Department of Medical Biochemistry and Biophysics at Karolinska Institutet in Sweden.
Using a process known as single cell sequencing, scientists at Karolinska Institutet have produced a detailed map of cortical cell types and the genes active within them. The study, which is published in the journal 'Science', marks the first time this method of analysis has been used on such a large scale on such complex tissue. The team studied over three thousand cells, one at a time, and even managed to identify a number of hitherto unknown types.

Stating that sleep is an essential biological process seems as obvious as saying that the sun rises every morning. Yet, researchers' understanding of the molecular mechanisms underlying the effects of sleep loss is still in its earliest stages. The risk for a host of metabolic disorders, including weight gain, diabetes, obesity, and cardiovascular disease, associated with reduced sleep is driving basic investigations on the topic.

Nova Southeastern University (NSU) researchers recently discovered that, contrary to prior belief, tissues of different mammalian organs have very different abilities to repair damage to their DNA.


The methylating enzyme DNMT (purple) cradles the DNA molecule as a methyl group is added to DNA.
The new study, published in Nature Communications, compares the breast cancer DNA 'methylome' with that of healthy individuals. The methylome provides a new picture of the genome and shows how it is epigenetically 'decorated' with methyl groups, a process known as DNA 'methylation'.


Researchers at Cold Spring Harbor Laboratory have uncovered a remarkable, new proofreading mechanism. In general, enzymatic machines are responsible for weeding out and correcting errors.
Cold Spring Harbor, NY - Building a protein is a lot like a game of telephone: information is passed along from one messenger to another, creating the potential for errors every step of the way. There are separate, specialized enzymatic machines that proofread at each step, ensuring that the instructions encoded in our DNA are faithfully translated into proteins. Scientists at Cold Spring Harbor Laboratory (CSHL) have uncovered a new quality control mechanism along this path, but in a remarkable role reversal, the proofreading isn't done by an enzyme. Instead, one of the messengers itself has a built-in mechanism to prevent errors along the way.


XPC DNA repair protein shown in two modes, patrolling undamaged DNA (in green) and bound to DNA damage site (magenta, with blue XPC insert opening the site).
Sites where DNA is damaged may cause a molecule that slides along the DNA strand to scan for damage to slow on its patrol, delaying it long enough to recognize and initiate repair. The finding suggests that the delay itself may be the key that allows the protein molecule to find its target, according to researchers at the University of Illinois at Chicago.

Scientists have shed light on how naturally occurring mutations can be introduced into our DNA.

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