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Protein interplay in muscle tied to life span

By Guest PostDecember 1, 2013Health, Scienceactivin equivalent, alzheimer's disease, ana maria hernandez, atg8a, autophagy, brain, brown university biologists, central culprit, chain, dawdle, dfoxo, female reproductive system, fly version, fruit flies, gene, hua bai, human aging biology, insulin producing cells, ipcs, life span, mammalian protein, marc tatar, menstrual cycle, misfolded proteins, molecular event, muscle, muscle fibers, muscle tissue, natural mechanism, ping kang, protein degradation, protein interplay, rolf bodmer

Brown University biologists have uncovered a complicated chain of molecular events that leads from insulin to protein degradation in muscles and significantly diminished life span in fruit flies. The new study in PLoS Genetics, which may have broad implications across species, identifies the fly version of the mammalian protein activin as the central culprit in the process.

PROVIDENCE, R.I. [Brown University] — Fruit flies are notoriously short-lived but scientists interested in the biology of aging in all animals have begun to understand why some fruit flies live longer than others. They have documented a direct association between insulin and life span, for example, and have observed a tradeoff between prolific reproduction and longevity. A new study, which may have broad implications across species, ties those findings more closely together by tracing an insulin signaling cascade through to protein quality control in muscle tissue and shortened life span. (more…)

Celebrated jumping frogs: For top hops, scientists look to Calaveras pros

By Guest PostOctober 21, 2013Sciencebiologist, brown university, bullfrog, calaveras county, calaveras pros, celebrated jumping frogs, frog jockeys, georgia tech university, guinness book, henry astley, jumping frog jubilee, justin bookey, muscle, rhode island, richard marsh, rosie the ribiter, technique, tendon, thomas roberts, trial and error, world records

The Calaveras County Jumping Frog Jubilee has entered the scientific record via a new paper in the Journal of Experimental Biology. Experienced bullfrog ‘jockeys’ at the event routinely get their frogs to jump much farther than researchers had ever measured in the lab. How? Decades of refined technique, uncommonly motivated humans and herps, and good old-fashioned large sample size.

PROVIDENCE, R.I. [Brown University] — One day, amid his decades-long study of how animals move, including how frogs jump, Brown University biologist Thomas Roberts found himself and colleague Richard Marsh puzzling over the Guinness Book of World Records. A bullfrog named Rosie the Ribiter reportedly had jumped more than 2.1 meters in a single hop at the Calaveras County Jumping Frog Jubilee in 1986, but scientific studies had never reported a bullfrog jump beyond 1.3 meters. (more…)

Size of Lunch Dictates Force of Crunch

By Guest PostFebruary 19, 2013Science3d, animal, animal bite force, animated computer model, biology letters, bite, bite strength relationship, brown university, co evolving foods, crush, crushing device, daily sustenance, ecology and evolution, ecosystem, elizabeth brainerd, eric lopresti, force, humans, jaw, length force relationship, maximum force, measure, muscle, muscle length, nicholas gidmark, nicolai konow, optimal value, phenomenon of physiology, piston activated, population, predators and prey, prey sizes, species, variable bite force, x ray markers, xray videos

Even in the same animal, not all bites are the same. A new study finds that because the force in a muscle depends on how much it is stretched, an animal’s bite force depends on the size of what it is biting. The finding has direct implications for ecology and evolution.

PROVIDENCE, R.I. [Brown University] — Many animals prefer food — snails, nuts, etc. — that must be cracked and crushed. Scientists have measured the maximum force of their impressive bites before, but a new study introduces a significant subtlety: bite force depends not only on the size and strength of the eater, but also the size of the eatee. That insight has important implications in the lives of predators and prey. (more…)

How Do Cells Tell Time? Scientists Develop Single-Cell Imaging to Watch the Cell Clock

By Guest PostNovember 18, 2012Science24 hour, activity, biological noise, cell, cell division, circadian clock, cyclic gene, cyclic protein, cyclical behavior, embryonic segmentation, embryonic segments, emilie delaune, gene, gene activation, life, lifespan, mesoderm, mitosis, molecular clock, muscle, nathan shih, nervous system, notch signaling pathway, oscillating pattern, oscillation, paul françois, phase, protein, sharon amacher, signal, signal reception, single cell, somites, synchronization, tissue segments, vasculature, vertebrae, visualization, visualize, zebrafish embryos

COLUMBUS, Ohio – A new way to visualize single-cell activity in living zebrafish embryos has allowed scientists to clarify how cells line up in the right place at the right time to receive signals about the next phase of their life.

Scientists developed the imaging tool in single living cells by fusing a protein defining the cells’ cyclical behavior to a yellow fluorescent protein that allows for visualization. Zebrafish embryos are already transparent, but with this closer microscopic look at the earliest stages of life, the researchers have answered two long-standing questions about how cells cooperate to form embryonic segments that later become muscle and vertebrae. (more…)

West Nile Virus More Prevalent in Low-income Neighborhoods, Study Finds

By Guest PostNovember 16, 2010Health, Sciencebird populations, coma, convulsions, disorientation, economic conditions, henri thomassen, low income neighborhoods, mosquito transmitted disease, mosquitoe, muscle, neck stiffness, North America, orange county, ryan harrigan, thomas smith, united states, west nile virus

Image credit: University of California

Low-income neighborhoods appear to be the most susceptible to West Nile virus, a mosquito-transmitted disease that is linked to more than 1,000 deaths since in the United States since 1999, according to new UCLA-lead research.

Using data on infected humans and mosquitoes from the West Nile virus hotspot of Orange County, Calif., from 2005-08, scientists found that per-capita income and other economic conditions were the single greatest predictor of occurrence, explaining 85-95 percent of the variation. While economic conditions have previously been linked to disease, the study is the first to use a rigorous statistical model. (more…)

Tag Archives: muscle

Protein interplay in muscle tied to life span

Celebrated jumping frogs: For top hops, scientists look to Calaveras pros

Size of Lunch Dictates Force of Crunch

How Do Cells Tell Time? Scientists Develop Single-Cell Imaging to Watch the Cell Clock

West Nile Virus More Prevalent in Low-income Neighborhoods, Study Finds