Free Republic

After a 40 year hunt, scientists have tracked down the genes responsible for fluorescent proteins in Obelia medusa - a type of jellyfish. Knowledge of these genes could lead to new fluorescent protein tags for use in cell biology. The discovery of the gene encoding green fluorescent protein (GFP) in the jellyfish Aequorea victoria paved the way for GFP to be introduced as a fluorescent tag in cell biology. It is used to track the positions and interactions of proteins in cells, and led to the Nobel prize in chemistry in 2008. Fluorescent proteins similar to GFP were discovered in Obelia medusa during biochemical...

Videos show T cells breaching the central nervous system's defences.A T cell (green) is seen moving with the flow of blood before crawling against it and exiting the blood vessel.Ingo Bartholomaeus et al, Nature 2009 Despite being surrounded by a supposedly unbreachable defensive line, the body's central nervous system can still be attacked by autoimmune diseases such as multiple sclerosis.Now, researchers led by Alexander Flügel, director of the Institute for Multiple Sclerosis Research at the University Medical Centre in Göttingen, Germany, have watched in real time as T cells — blood cells linked to the immune response — penetrate the...

Live-cell fluorescence imaging identifies bona fide reprogrammed cells.Fluorescence imaging could help resolve whether iPS cells have been properly programmed.Alamy The next tools for reprogramming cells to an embryonic-like state might just be a camera and a set of fluorescently tagged antibodies. Researchers imaged more than a million human cells in vitro as they changed from skin tissue cells, known as fibroblasts, into colonies of induced pluripotent stem (iPS) cells. As expected, many similar-looking colonies appeared, but only very few consisted of fully reprogrammed iPS cells. After assessing which were which, researchers led by Thorsten Schlaeger and George Daley of the...

US scientists have developed a sensor system for profiling the protein content of human blood serum without needing individual receptors for each separate protein. The technique could be used to provide cheap preliminary disease diagnosis information, saving time and money by reducing unnecessary testing.There is a direct link between levels of protein in human serum and disease, making protein levels an attractive target for sensors and diagnostics. However, with over 20,000 proteins present in human serum at a range of different concentrations, developing an effective sensor has been a challenging task.Pattern recognition sensing uses detector systems that interact with many...

Tissues in axolotl amputees regenerate themselves by “memory” Given a chance to regrow a limb, salamanders don’t change a thing. Since the 18th century, scientists have puzzled over how salamanders regenerate amputated limbs and have looked for clues to regrow human limbs. Researchers thought they knew part of the answer: Cells at the wound site would lose their identities as they turned back their developmental clocks to become pluripotent stem cells — capable of developing into many cell types in the body — and then recreate the lost limb. But a new study published July 2 in Nature and led...

Biologists’ favorite glowing marker may play a role in cellular business Green fluorescent protein, the darling of cell biologists and biomedical researchers, may do more than give off light. When the protein fluoresces — allowing researchers to see where cells and proteins boldly glow in petri dishes and living organisms — it also gives up electrons, a team reports online April 26 in Nature Chemical Biology. The research suggests a possible new function of the protein; its normal role has remained a puzzle despite its widespread use in laboratories. “This is a totally unexpected twist,” comments Mikhail Matz of the...

Enlarge ImageMiraculous birth. A Chinese group isolated stem cells from mouse ovaries, transplanted them into sterilized mice, and got these normal babies. Credit: Kang Zou et al., Nature Cell Biology Advance Online Publication (12 April 2009) A new study challenges the long-held belief that female mammals start life with a limited number of eggs and cannot produce new ones after birth. For the first time, a Chinese group has found mouse cells that produce new eggs when transplanted into sterilized mice and give rise to normal offspring. The findings are already inflaming the debate over when and how female...

Green fluorescent protein bags the biggest gong in science. Aequorea victoria, source of the green fluorescent protein.G. OCHOCKI/SCIENCE PHOTO LIBRARY The molecule responsible for a jellyfish's glow has won its discoverer and developers this year's Nobel Prize in Chemistry. The green fluorescent protein (GFP) has revolutionized medical and biological science by providing a way to track the activity of individual proteins within a living cell, and thereby monitor how genes are expressed. The prize is shared equally between three scientists: Osamu Shimomura, now an emeritus professor at the Marine Biological Laboratory in Woods Hole, Massachusetts, Martin Chalfie of Columbia University...