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. Architect genes are responsible for organizing structures of the body during embryonic development. Some of them, namely the Hox genes, are involved in the formation of forelimbs. They are activated in two successive waves, enabling the formation of the arm, then the hand. A team led by Denis Duboule, a professor at UNIGE and EPFL, Switzerland, and Guillaume Andrey, from the Frontiers in Genetics National Research Center, uncovered the workings of this complex process. http://phys.org/news289738048.html Biology Thu, 06 Jun 2013 14:00:08 EST news289738048 (Phys.org) —A fundamental question in the evolution of animal body plans, is where did the head come from? In animals with a clear axis of right-left symmetry, the bilaterians, the head is where the brain is, at the anterior pole of the body. Little is known about the possible ancestor of bilaterians. Fortunately their sister group from that same progenitor, the cnidarians, can be studied in parallel today to give some clues. Cnidarians are creatures like jellyfish, hydra, and sea anemone which possess rudimentary nerve nets, but no clear brain. They all have just a single orifice to the external world, which basically does it all. In a recent paper published in PLOS Biology, researchers from the University of Bergen in Norway compared gene expression patterns in sea anemone (Nematostella vectensis, Nv) with that from a variety of bilaterian animals. They found that the head-forming region of bilaterians is actually derived from the aboral, the opposite-oral, side of the ancestral body plan. http://phys.org/news283710442.html Biology Thu, 28 Mar 2013 17:28:14 EST news283710442 Researchers have provided a glimpse at genetic expression in long-extinct fossil dinosaurs. This new insight comes from the discovery of a correlation between the genetic patterning observed in today's chickens and crocodiles, and the pattern of different bone shapes along their spines. For the first time a direct correlation between the genetic expression and morphological variation is identified. http://phys.org/news270197432.html Biology Tue, 23 Oct 2012 08:40:03 EST news270197432 The American paddlefish -- known for its bizarre, protruding snout and eggs harvested for caviar -- duplicated its entire genome about 42 million years ago, according to a new study published in the journal Genome Biology and Evolution. This finding may add a new twist to the way scientists study how fins evolved into limbs since the paddlefish is often used as a proxy for a more representative ancestor shared by humans and fishes. http://phys.org/news263556252.html Biology Tue, 07 Aug 2012 11:04:26 EST news263556252 Biologists have long assumed that all jawed vertebrates possess a full complement of nearly identical genes for critical aspects of their development. But a paper in the December 16 issue of Science with Benjamin King of the Mount Desert Island Biological Laboratory (MDIBL) as lead author shows that elasmobranchs, a subclass of cartilaginous fishes, lack a cluster of genes, HoxC, formerly thought to be essential for proper development. http://phys.org/news243179333.html Biology Thu, 15 Dec 2011 14:00:20 EST news243179333 In a surprising and unexpected discovery, scientists at NYU Langone Medical Center have found that a single type of gene acts as a master organizer of motor neurons in the spinal cord. The finding, published in the September 9, 2010 issue of Neuron, could help scientists develop new treatments for diseases such as Lou Gehrig's disease or spinal cord injury. http://phys.org/news203169126.html Medicine & Health Wed, 08 Sep 2010 13:10:01 EST news203169126 An unknown function that regulates how stem cells produce different types of cells in different parts of the nervous system has been discovered by Stefan Thor, professor of Developmental Biology, and graduate students Daniel Karlsson and Magnus Baumgardt, at Linköping University in Sweden. The results improve our understanding of how stem cells work, which is crucial for our ability to use stem cells to treat and repair organs. The findings are publishing next week in the online, open-access journal PLoS Biology. http://phys.org/news192817534.html Biology Tue, 11 May 2010 18:30:01 EST news192817534 Like all vertebrates, snakes, mice and humans have in common a skeleton made of segments, the vertebrae. But a snake has between 200-400 ribs extending from all vertebrae, from the neck to the tail-end, whereas mice have only 13 pairs of ribs, and humans have 12 pairs, in both cases making up the ribcage. In the latest issue of Developmental Cell, researchers from the Instituto Gulbenkian de Ciencia, in Portugal, reveal that, contrary to what was thought, making ribs is not the default state for vertebrates, but is actually an active process of balancing the activities of a remarkable class of genes - the Hox genes. http://phys.org/news191583046.html Medicine & Health Tue, 27 Apr 2010 10:40:16 EST news191583046 Vertebrates have in common a skeleton made of segments, the vertebrae. During development of the embryo, each segment is added in a time dependent manner, from the head-end to the tail-end: the first segments to be added become the vertebrae of the neck, later segments become the vertebrae with ribs and the last ones the vertebra located in the tail (in the case of a mouse, for example). In this process, it is crucial that, on the one hand, each segment, as it matures, becomes the correct type of vertebra and, on the other, that the number of vertebrae in the skeleton, and therefore the size of the spine, are minutely controlled. http://phys.org/news175861637.html Medicine & Health Tue, 27 Oct 2009 11:40:01 EST news175861637