Signal

Plants respond similarly to signals from friends, enemies

Two soil-dwelling strangers ?a friend and a foe ?approach a plant and communicate with it in order to enter a partnership. The friend wants to trade nitrogen for food. The foe is a parasite that wants to burrow in and harm the plant. In a new finding published in Proceedings of the National Academy of Sciences, researchers at North Carolina State University have found that the two strange...

Signaling protein builds bigger, better bones in mice

In a new study, researchers present a “cautionary tale?about what may go wrong when using the fledgling science of proteomics to devise a diagnostic test for cancer. In the February 16 issue of the Journal of the National Cancer Institute, researchers from The University of Texas M. D. Anderson Cancer Center detail why an experimental test intended to identify early ovarian cancer from a...

Bound for destruction: Ubiquitination protects against improper Notch signaling

The is an important molecular signaling mechanism whose existence has beenknown, or at least hinted at, for nearly a century since theidentification of a mutant strain of Drosophila fruit flies with“notched?wings in Thomas Hunt Morgan’s lab in 1910. Later studiesrevealed that the Notch gene encodes a receptor protein tha...

Viral protein influences key cell-signaling pathway

New research shows that a protein produced by a cancer-causing virus influences a key signaling pathway in the immune cells that the virus infects. This stimulates the cells to divide, helping the virus spread through the body. T...

Computational Method Speeds Mapping of Cell Signaling Networks

For decades, scientists have been studying how external information gets transmitted from outside of cells to the control centers inside them that trigger particular responses. But cell signaling networks are so complex that mapping them has been a slow, arduous process. Now, a research team from Stanford, MIT and Harvard has developed a new method for charting cellular signaling networks...

Researchers find promising cancer-fighting power of synthetic cell-signaling molecule

Novel anti-cancer compounds called Enigmols suppress the growth of human cell lines representing cancers of the prostate, breast, colon, ovary, pancreas, brain and blood, and reduce tumors in three animal studies, new research shows. In addition, Enigmols did not show side effects at effective doses, according to the research conducted at the Georgia Institute of Technology, Emory Universi...

Edible bivalves as a source of human pathogens: signals between vibrios and the bivalve host.

Clams, mussels and oysters are important vehicles for the transmission of enteric diseases when consumed raw or undercooked. Vibrio species, including human pathogens, are particularly abundant in bivalve tissues, where they can persist even after cleaning procedures, thus representing a potential risk for human health. Although different environmental factors are well known to affect the persist...

Scientists discover that three overlapping signals in embryo help get the backbone right

A major step in the development of the vertebrate embryo - the establishment of a back that morphs into a brain, spinal cord and muscles - turns out to be so important that the body uses at least three signals to make sure it happens properly. The discovery, reported this month in the journal Developmental Cell by researchers at the University of California, Berkeley, finally explains an...

After a time-shift, mixed signals from the circadian clock

Circadian rhythms in mammalian behavior, physiology, and biochemistry are controlled by the central clock within a brain structure known as the suprachiasmatic nucleus (SCN). The clock is synchronized to environmental cycles of light and dark. It is well known, from everyday experience, that adjusting to new light schedules takes several days, though the details of how this adaptation takes place...

Researchers make surprise discovery that some neurons can transmit three signals at once

Generations of neuroscientists have been indoctrinated into believing that our senses, thoughts, feelings and movements are orchestrated by a communication network of brain cells, or neurons, each responsible for relaying one specific chemical message called a neurotransmitter. Either neurons release a neurotransmitter that excites a neighboring cell, thereby triggering an electrical discharge an...

Structure-building cell signals also may influence learning and memory

A Burnham Institute study has found that one of the cell's largest families of signaling molecules, called ephrins, which are known to regulate the development of nerve cells, also controls nerve cells' ability to engulf critical chemicals and proteins for learning and memory. These findings, the first to link these molecular semaphores to this important nerve cell function, appear in the May iss...

Fox Chase study shows that weakened T-cell receptor signals change T-cell lineage

The immune system is a marvel of versatility, creating a variety of cells that develop in different ways to protect the body. To carry out these tasks, immune cells follow a career path that forks at various points in their development. In a report in the May 2005 issue of Immunity, Fox Chase Cancer Center scientists led by immunologists David L. Wiest, Ph.D. and Dietmar J. Kappes, Ph.D., show th...

Immune system's distress signal tells bacteria when to strike back

The human opportunistic pathogen, Pseudomonas aeruginosa, has broken the immune system's code, report researchers from the University of Chicago, enabling the bacteria to recognize when its host is most vulnerable and to launch an attack before the weakened host can muster its defenses. In the 29 July 2005 issue of Science, the researchers show how this lethal organism detects interferon-g...

New defibrillator signals doctor of patient's irregular heartbeat or device malfunction

Loyola first in U.S. to implant new FDA-approved device In a major advance for heart patients, Loyola University Health System is the first hospital in the U.S. to implant into a patient a new FDA-approved defibrillator which automatically signals the doctor via wireless satellite transmission if the patient's heart beats abnormally or if the device malfunctions, e.g., battery failure.</p...

Fluorescing lab worms signal longer life spans

University of Colorado at Boulder scientists have used a fluorescent marker to predict the individual life spans of identical worms that were genetically engineered to illuminate stress levels, implying living organisms have "hidden physiological states" that dictate their ability to deal with the rigors of life. According to CU-Boulder Research Associate Shane Rea, the genetically identic...

FSU biologists describe key role of signal-transcribing gene during cell cycle

Study in Oct. 1 'Development' shows when, where Alzheimer's, some cancers and genetic ills beginT. Biologists at Florida State University have uncovered the pivotal role of a gene called "Cut" that acts as a sort of middleman in cell-to-cell communication. A DNA-binding protein, Cut interprets and transcribes the developmental signals sent through the "Notch" gene, which regulates a layer...

Overbearing colored light may reveal a second mechanism by which birds interpret magnetic signals

Magnetic orientation is critical to the migratory success of many bird species. By studying the influence of light on the ability of migratory birds to orient to magnetic signals, researchers have found clues to suggest that birds' orientation abilities may be more complex than previously thought and that birds may be able to interpret magnetic signals by more than one mechanism. The work is repo...

Leptin-signaling Protein Maintains Normal Body Weight And Energy Balance In Mice

32% increase of African fish supply needed by 2020 just to maintain consumption levels Calling fisheries critical for nourishing the poor and for helping Africa cope with the health, economic and social devastation of problems like HIV and AIDS, the New Partnership for Africa's Development (NEPAD), the WorldFish Center and partners are making an urgent appeal to boost the continent's fish...

Neurotransmitters signal aggressive cancer, offer potential for early diagnosis

Nerves talk to each other using chemicals called neurotransmitters. One of those "communication chemicals," aptly named GABA (gamma amino butyric acid), shows up in unusually high amounts in some aggressive tumors, according to a new study from Washington University School of Medicine in St. Louis. The researchers investigated metastatic neuroendocrine tumors, which include aggressive type...

Prostate cancer uses Wnt signaling proteins to promote growth of bone tumors

Prostate cancer is a cruel disease. Left untreated, prostate cancer cells often metastasize, or spread, to bone where they form fracture-prone tumors that are extremely painful. More than 80 percent of men who die from prostate cancer die with metastatic disease in their bones. But scientists know very little about how migrating prostate cancer cells set up housekeeping in bone tissue and...

A resetting signal keeps circadian rhythm on track in Drosophila fruit flies

A Brandeis University study published this week in Nature shows for the first time that a molecular signal maintains coherence among brain clock cells that regulate daily activity of Drosophila melanogaster (fruit flies). The two key groups of neurons control morning and evening activity and are maintained in synch even when the flies are plunged into darkness for extended periods of time. <...

Yale scientists decipher 'wiring pattern' of cell signaling networks

A team of scientists at Yale University has completed the first comprehensive map of the proteins and kinase signaling network that controls how cells of higher organisms operate, according to a report this week in the journal Nature. The study is a breakthrough in understanding mechanisms of how proteins operate in different cell types under the control of master regulator molecules call...

Mayo Clinic collaboration discovers protein amplifies DNA injury signals

A Mayo Clinic-led research collaboration has discovered that the protein MDC1 amplifies weak DNA injury signals so genetic repair can begin. Once amplified, even low-level damage signals become strong enough to activate the cell's natural repair processes while the injury is most tractable to repair. How this "distress call" was communicated wasn't clear until this finding, which appears...

Research details how a virus hijacks cell signals to cause infection

A common virus that causes meningitis and heart inflammation takes a "back door" approach to evade natural barriers, then exploits biological signals to infect human cells. Broadening knowledge of how viruses cause infection, a new study describes elaborate methods that the virus has evolved to bypass the body's defenses. "This study helps to explain how group B coxsackieviruses infect cel...

Macrophage signaling may affect hormone resistance in prostate tumors

Interaction between prostate cancer cells and immune cells called macrophages may be a source of inflammatory signals capable of impacting the effectiveness of androgen antagonists, the most common and effective treatment for prostate cancer, according to a new study by researchers at the University of California, San Diego (UCSD) School of Medicine. Male hormones called androgens are es...

Chemical signaling helps regulate sensory map formation in the brain

Researchers from the University of Chicago have uncovered an important mechanism used by the developing brain to pattern nerve connections in the part of the brain that interprets visual signals. In the process, they have provided the first experimental evidence for a decades-old model of how nerve cells establish distant connections in a way that can consistently relay spatial information....

Ritalin packs punch by elevating norepinephrine, suppressing nerve signal transmissions

Methylphenidate (Ritalin) elevates norepinephrine levels in the brains of rats to help focus attention while suppressing nerve signal transmissions in the sensory pathways to make it easier to block out extraneous stimuli, a Philadelphia research team has found. Their report in the Journal of Neurophysiology helps explain how a stimulant aids people with attention deficit and hyperactivity...

Nanowire arrays can detect signals along individual neurons

Opening a whole new interface between nanotechnology and neuroscience, scientists at Harvard University have used slender silicon nanowires to detect, stimulate, and inhibit nerve signals along the axons and dendrites of live mammalian neurons. "We d...

Flick of whiskers helps tease out brain's 'shadow' signaling system

By blowing gentle puffs of air onto a mouse's whiskers and watching how its brain reacts, scientists are discovering that a long-overlooked signaling system in the brain is crucial to our everyday activity. The work is the latest in a growing body of evidence that star-shaped brain cells known as astrocytes aren't simply support cells but are stars of the brain in their own right, say rese...

New study reveals signaling pathways required for expansion of pancreas stem cells

IDDM, which used to be referred to as Type 1 diabetes, results from selective destruction of insulin-producing pancreatic islet beta cells by the body's immune system. Islet beta cells are spread throughout the pancreas and are made up of two types of cells: alpha cells, which make glucagon, a hormone that raises the level of glucose (sugar) in the blood, and beta cells, which make insulin. <...

Selectively blocking inflammatory signals may protect mice from MS

A new way to preserve the cells that surround and protect nerves could lead to new treatments for demyelinating diseases such a multiple sclerosis, a research team reports in the May 10, 2006, issue of the Journal of Neuroscience. The approach grew out of a novel explanation, quickly gaining followers, for the mechanism of nerve damage caused by multiple sclerosis. Instead of concentratin...

Increased sensitivity to nerve signals keeps diabetes at bay

Nerve signals relayed directly to the pancreas after eating a meal play a critical role in normal blood sugar control, according to a report in the June 7, 2006, Cell Metabolism. Therefore, drugs that increase the sensitivity to such signals might offer a new approach to diabetes treatment, the researchers said. Mice in which the pancreas cells that produce insulin, or beta cells, lack so-...

Nanotubes used for first time to send signals to nerve cells

Texas scientists have added one more trick to the amazing repertoire of carbon nanotubes -- the ability to carry electrical signals to nerve cells. Nanotubes, tiny hollow carbon filaments about one ten-thousandth the diameter of a human hair, are already famed as one of the most versatile materials ever discovered. A hundred times as strong as steel and one-sixth as dense, able to conduct...

'Cellular antennae' on algae give clues to how human cells receive signals

By studying microscopic hairs called cilia on algae, researchers at UT Southwestern Medical Center have found that an internal structure that helps build cilia is also responsible for a cell's response to external signals. Cilia perform many functions on human cells; they propel egg and sperm cells to make fertilization possible, line the nose to pick up odors, and purify the blood, among...

Salk scientists untangle steroid hormone signaling in plants

When given extra shots of the plant steroid brassinolide, plants "pump up" like major league baseball players do on steroids. Tracing brassinolide's signal deep into the cell's nucleus, researchers at the Salk Institute for Biological Studies have unraveled how the growth-boosting hormone accomplishes its job at the molecular level. The Salk researchers, led by Joanne Chory, a professor i...

Key molecular signaling switch involved in allergic disease identified

A research team has identified a key enzyme responsible for triggering a chain of events that results in allergic reaction, according to new study findings published online this week in Nature Immunology. The work by researchers from Virginia Commonwealth University, the Hospital for Special Surgery and Weill Cornell Medical College in New York sets the stage for development of new strateg...

Signaling for cartilage

Skeletal progenitor cells differentiate into cartilage cells when one master gene actually suppresses the action of another, said Baylor College of Medicine researchers in a report that appears online in the journal Proceedings of the National Academy of Sciences. Skeletons are made of bone and cartilage cells that are differentiated from the same multipotent stem cell, said Dr. Brendan Le...

Molecular mechanism provides intra-cellular traffic signal

City planners could learn a lesson or two from tiny cells on how to maximize traffic flow. The molecula...

Newly discovered behavior in cancer cells signals dangerous metastasis

The most aggressively malignant cancer cells have a "toggle switch" that enables them to morph into highly mobile cells that invade other tissues and then nest comfortably in their new surroundings, a new study in rats suggests. This picture of how cancer cells shift between two alternating states -- travelers and nesters -- represents a new understanding of how cancer metastasizes, or spr...

Shrinking ponds signal warmer, dryer Alaska

A first-of-its kind analysis of fifty years of remotely sensed imagery from the 1950s to 2002 shows a dramatic reduction in the size and number of more than 10,000 ponds in Alaska. The analysis, by University of Alaska Fairbanks scientists and published this week in the Journal of Geophysical Research, indicates that these landscape-level changes in arctic ponds are associated with recent climate...