http://phys.org/ en-us Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. (PhysOrg.com) -- The major difference between plant and animal cells is the photosynthetic process, which converts light energy into chemical energy. When light isn't available, energy is generated by breaking down carbohydrates and sugars, just as it is in animal and some bacterial cells. Two cellular organelles are responsible for these two processes: the chloroplasts for photosynthesis and the mitochondria for sugar breakdown. New research from Carnegie's Eva Nowack and Arthur Grossman has opened a window into the early stages of chloroplast evolution. Their work is published online by the Proceedings of the National Academy of Sciences in the week of February 27-March 2. http://phys.org/news249577081.html Biology Mon, 27 Feb 2012 15:00:05 EST news249577081 Researchers at Albert Einstein College of Medicine of Yeshiva University have discovered the first known mechanism by which cells control the survival of messenger RNA (mRNA) -- arguably biology's most important molecule. The findings pertain to mRNAs that help regulate cell division and could therefore have implications for reversing cancer's out-of-control cell division. The research is described in today's online edition of the journal Cell. http://phys.org/news243776230.html Biology Thu, 22 Dec 2011 12:00:09 EST news243776230 Growing up just got more complicated. Thomas Jefferson University biochemistry researchers have shown for the first time that the receptor for a major insect molting hormone doesn't activate and repress genes as once thought. In fact, it only activates genes, and it is out-competed by a heme-binding receptor to repress the same genes during the larval to pupal transition in the fruit fly. http://phys.org/news237125049.html Chemistry Thu, 06 Oct 2011 13:04:19 EST news237125049 University of Alberta researchers have identified a key regulator that controls the speed of development in the fruit fly. When the researchers blocked the function of this regulator, animals sped up their rate of development and reached maturity much faster than normal. http://phys.org/news236427933.html Biology Wed, 28 Sep 2011 12:00:01 EST news236427933 A new technique developed by researchers at RIKEN has clarified the location and dynamics of specific metabolites in a single cell of the alga Chara australis. The findings reveal that these metabolites are regulated and fluctuate under stress conditions, providing insight into previously-unknown functions of the vacuole in cellular processes. http://phys.org/news235130368.html Biology Tue, 13 Sep 2011 10:59:59 EST news235130368 (PhysOrg.com) -- Using a new technique in which models of primitive cells are constructed from the bottom up, scientists have demonstrated that the structure of a cell's membrane and cytoplasm may be as important to cell division as the specialized machinery -- such as enzymes, DNA or RNA -- which are found within living cells. Christine Keating, an associate professor of chemistry at Penn State University, and Meghan Andes-Koback, a graduate student in the Penn State Department of Chemistry, generated simple, non-living model "cells" with which they established that asymmetric division -- the process by which a cell splits to become two distinct daughter cells -- is possible even in the absence of complex cellular components, such as genes. The study, which will be published in the Journal of the American Chemical Society, may provide important clues to how life originated from non-life and how modern cells came to exhibit complex behaviors. http://phys.org/news224953971.html Chemistry Wed, 18 May 2011 16:13:23 EST news224953971 EU-funded researchers from Germany and Poland have made some groundbreaking discoveries about cell cytoplasm viscosity, which could further our knowledge of the cytoplasm of cancer cells. http://phys.org/news224760782.html Nanotechnology Mon, 16 May 2011 11:20:02 EST news224760782 Scientists from the Helmholtz Centre for Infection Research (HZI) in Braunschweig, Germany have discovered a new, hitherto unknown mechanism of Salmonella invasion into gut cells: In this entry mode, the bacteria exploit the muscle power of cells to be pulled into the host cell cytoplasm. Thus, the strategies Salmonella use to infect cells are more complex than previously thought. According to the World Health Organization, the number of Salmonella infections is continuously rising, and the severity of infections is increasing. One of the reasons for this may be the sophisticated infection strategies the bacteria have evolved. The striking diversity of invasion strategies may allow Salmonella to infect multiple cell types and different hosts. http://phys.org/news222608963.html Biology Thu, 21 Apr 2011 12:49:37 EST news222608963 (PhysOrg.com) -- There's no question, drugs work in treating disease. But can they work better, and safer? http://phys.org/news222586066.html Nanotechnology Thu, 21 Apr 2011 06:28:11 EST news222586066 Active transport processes in cells ensure that proteins with specialized local functions reach their intracellular destinations. Impaired transport causes cellular dysfunction or even cell death. Scientists from Ludwig-Maximilians-Universitaet in Munich and Helmholtz Zentrum Muenchen have now revealed how such a transport complex recognizes its cargo and assembles. http://phys.org/news222514878.html Biology Wed, 20 Apr 2011 10:43:41 EST news222514878 A great many cellular processes are switched on or off by the modification of a given enzyme or other protein by addition of a phosphate molecule, known as phosphorylation. This regulatory activity occurs widely in the cytoplasm, but can take place in the nucleus as well. Recent work has shown the HP1α, a protein that guides the formation of heterochromatin, a form of the DNA-protein structure know as chromatin, is also subject to this post-translational modification, but the biological meaning of this event has remained unresolved. http://phys.org/news218885099.html Biology Wed, 09 Mar 2011 09:25:09 EST news218885099 One bad apple is all it takes to spoil the barrel. And one misfolded protein may be all that's necessary to corrupt other proteins, forming large aggregations linked to several incurable neurodegenerative diseases such as Huntington's, Parkinson's and Alzheimer's. http://phys.org/news217270341.html Medicine & Health Fri, 18 Feb 2011 16:53:16 EST news217270341 In a technique that could eventually shed light on how gene expression influences human disease, scientists at Albert Einstein College of Medicine of Yeshiva University have for the first time ever successfully visualized single molecules of naturally-occurring messenger RNA (mRNA) transcribed in living mammalian cells. The scientific achievement is detailed in the January 16 online edition of Nature Methods. http://phys.org/news214408435.html Chemistry Sun, 16 Jan 2011 13:54:36 EST news214408435 The so-called immune receptor Rx, conferring the resistance of some potato cultivars against potato virus X, does recognise the viruses in the cytoplasm, but – unexpectedly – its presence in the nucleus is also required for an effective defence response. Erik Slootweg and Wladimir Tameling, scientists of two different Chair Groups of Wageningen University, The Netherlands, have with a number of colleagues published this striking finding in two papers published in the same issue of the scientific journal The Plant Cell. http://phys.org/news213358193.html Biology Tue, 04 Jan 2011 10:10:09 EST news213358193 The cell signaling pathway known as Wnt, commonly activated in cancers, causes internal membranes within a healthy cell to imprison an enzyme that is vital in degrading proteins, preventing the enzyme from doing its job and affecting the stability of many proteins within the cell, researchers at UCLA's Jonsson Comprehensive Cancer Center have found. http://phys.org/news212333352.html Biology Thu, 23 Dec 2010 13:29:57 EST news212333352 Researchers at the University of Georgia have discovered a central switch that controls whether cells move or remain stationary. The misregulation of this switch may play a role in the increased movement of tumor cells and in the aggressiveness of tumors themselves. http://phys.org/news210954067.html Biology Tue, 07 Dec 2010 14:21:31 EST news210954067 (PhysOrg.com) -- Researchers at the University of Pennsylvania School of Medicine have documented a novel form of splicing in the cytoplasm of a nerve cell, which dictates a special form of a potassium channel protein in the outer membrane. The channel protein is found in the dendrites of hippocampus cells -- the seat of memory, learning, and spatial navigation -- and is involved in coordinating the electrical firing of nerve cells. http://phys.org/news209229549.html Medicine & Health Wed, 17 Nov 2010 16:10:01 EST news209229549 (PhysOrg.com) -- Dr. Joseph Glavy at Stevens Institute of Technology studies the smallest and most basic elements of life. The Assistant Professor of Chemical Biology runs the Glavy Lab, where advanced student scientists study the nuclear pore complexes (NPCs) in cells, observing the minutest mechanisms of life as they unfold during mitosis. The Glavy Lab's formal purpose is to study the NPC at the molecular level in the pursuit of the unknown or unexpected in the well-studied but not always well-understood nuclei of living cells. http://phys.org/news209134853.html Medicine & Health Tue, 16 Nov 2010 13:01:31 EST news209134853 Researchers have developed a promising new approach to vaccination for rotavirus, a common cause of severe diarrheal disease that is responsible for approximately 500,000 deaths among children in the developing world every year. In a study published in the November issue of Clinical and Vaccine Immunology, a vaccine delivered as nasal drops effectively induced an immune response in mice and protected them from rotavirus infection. The new vaccine delivery system has also been tested successfully and found to be heat stable with tetanus and is currently being tested with diphtheria and pertussis. http://phys.org/news209102144.html Medicine & Health Tue, 16 Nov 2010 04:20:02 EST news209102144 Researchers have uncovered a potential source of blood-derived biomarkers for certain kinds of cancer, according to a study. http://phys.org/news207902523.html Medicine & Health Tue, 02 Nov 2010 08:10:01 EST news207902523 A new study reveals that two enzymes help immune cells deploy pathogen-killing traps by unraveling and using the chromatin (DNA and its associated proteins) contained in the cells' nuclei to form defensive webs. The study appears online on October 25 in The Journal of Cell Biology. http://phys.org/news207230122.html Biology Mon, 25 Oct 2010 13:20:03 EST news207230122 Refinements to a fluorescent calcium ion indicator give scientists a powerful tool for tracking neuronal activity in the living brain http://phys.org/news206961179.html Medicine & Health Fri, 22 Oct 2010 10:13:20 EST news206961179 Scientists from The Scripps Research Institute have solved a long-standing mystery of how cells conduct "quality control" to eliminate the toxic effects of a certain kind of error in protein production. The findings may lead to a better understanding of a host of neurodegenerative diseases. http://phys.org/news203522608.html Biology Sun, 12 Sep 2010 15:03:59 EST news203522608 (PhysOrg.com) -- UC Berkeley researchers Karsten Weis, Jan Liphardt, and colleagues have used fluorescent probes called quantum dots to determine which molecules get into the nucleus via its nano-pores and which get kicked back out. Their findings could help design drugs that can get through the pores and target a cell's DNA. http://phys.org/news202628740.html Nanotechnology Thu, 02 Sep 2010 06:45:54 EST news202628740 (PhysOrg.com) -- For the first time, it's possible to experimentally capture a global snapshot of the conformation of thousands of RNA molecules in a cell. The finding is important because this scrappy little sister of DNA has recently been shown to be much more complex than previously thought. http://phys.org/news202567629.html Biology Wed, 01 Sep 2010 13:47:33 EST news202567629 Researchers at The Pennsylvania State University College of Medicine, Hershey, Pennsylvania have discovered that the Opioid Growth Factor (OGF, [Met5]-enkephalin) and its receptor, OGFr, a clinically important system with potent antitumor properties, has controlled entry from the cytoplasm to the nucleus. The nucleocytoplasmic passage of OGF-OGFr is critical to cell proliferation and suggests that there are hierarchical levels of nuclear import. This discovery, reported in the September 2010 issue of Experimental Biology and Medicine, provides new insights into understanding the pathobiology of diseases related to this native biological system, and contributes to the development of new agents that will enhance treatment effectiveness. http://phys.org/news201799939.html Biology Mon, 23 Aug 2010 16:50:01 EST news201799939 When searching for long-lost treasure, sometimes all you need is a good flashlight. http://phys.org/news199027868.html Biology Thu, 22 Jul 2010 14:31:26 EST news199027868 Scientists are reporting discovery of a way to help proteins such as the new generation of protein-based drugs -- sometimes heralded as tomorrow's potential "miracle cures" -- get past the biochemical "Entrance Forbidden" barrier that keeps them from entering cells and doing their work. http://phys.org/news198329350.html Chemistry Wed, 14 Jul 2010 13:00:03 EST news198329350 Intrahepatic cholangiocarcinoma (ICC) is a cancer of the bile duct in the liver. The clear cell subtype of ICC is a rare cancer; until now, only 8 cases have been reported. The number of reports is so small that a detail description of clear cell ICC is valuable. http://phys.org/news194696950.html Medicine & Health Wed, 02 Jun 2010 12:20:03 EST news194696950 Many tumor cells would not be viable due to aberrant chromosome distribution if they had not developed a special trick. Scientists from the German Cancer Research Center have investigated which genes are responsible for this survival strategy of cancer cells. The revealed that cancer cells rely on the tension of specific protein fibers to be able to multiply. Thus, proteins which maintain this tension are promising targets for new, target-specific anticancer drugs: If they are switched off, cancer cells die. http://phys.org/news194606936.html Medicine & Health Tue, 01 Jun 2010 10:29:17 EST news194606936