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Thelasko writes "Ever wonder why heads of statetend to age twice as fast as the rest of us? New research shows that adrenaline may damage DNA, potentially accelerating aging."

Reader Ostracus informs us of research led by Michael Ehlers of Duke University that has identified a molecule, myosin Vb (five-b), that seems to be a critical component in the formation of memory. "A major puzzle for neurobiologists is how the brain can modify one... synapse at a time in a brain cell and not affect the thousands of other connections nearby. Plasticity, the ability of the brain to precisely rearrange the connections between its nerve cells, is the framework for learning and forming memories ... The discovery of a molecule that moves new receptors to the synapse so that the neuron... can respond more strongly helps to explain several observations about [brain] plasticity ... [The researchers] found that the myosin Vb molecule in hippocampal neurons responded to a flow of calcium ions from the synaptic space by popping up and into action. One end of the myosin is attached to meshlike actin filaments so it can 'walk' to the end of the nerve cells where receptors are. On its other end, it tows an endosome, a packet that contains new receptors. 'These endosomes are like little memories waiting to happen,' Ehlers said."

esocid tips us to news out of Duke University Medical Center, where researchers have discovered a type of microRNA that is related to the ability of zebrafish to regenerate lost or damaged organs. This is the result of a study initiated after it was discovered that zebrafish were able to recover from "massive injury" to the heart through their own regenerative biology. The scientists hope to be able to use this information to bring about similar healing in humans. Zebrafish have also been helpful in cancer research. "In zebrafish, one or more microRNAs appear to be important to keep regeneration on hold until the fish needs new tissue, the Duke researchers say. In response to an injury, the fish then damp down levels of these microRNAs to aid regrowth. Poss and many other cell biologists believe that mammals may have the same tissue regeneration capability as zebrafish, salamanders and newts, but that it is locked away somewhere in our genome, silenced in the course of evolution."