tailieunhanh - Báo cáo sinh học: "Neuronal remodeling on the evolutionary timescale"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Neuronal remodeling on the evolutionary timescale. | Journal of Biology BioMed Central Minireview Neuronal remodeling on the evolutionary timescale Ithai Rabinowitch and William Schafer Address MRC Laboratory of Molecular Biology Hills Road Cambridge CB2 0QH UK. Email wschafer@ Published 15 December 2008 Journal of Biology 2008 7 37 doi jbiol102 The electronic version of this article is the complete one and can be found online at http content 7 10 37 2008 BioMed Central Ltd Abstract Despite its remarkable capacity to undergo change at timescales ranging from a fraction of a second to a lifetime there are many aspects of the nervous system that can be modified only at the enormously longer evolutionary timescale. A new study in BMC Biology using nematodes illustrates such evolutionary neuronal remodeling. One of the hallmarks of the nervous system is its exceptional capacity to remodel itself through a huge variety of complex mechanisms occurring at multiple timescales. Within an individual s lifetime parameters such as synaptic efficacy membrane excitability and micro-morphology can undergo major changes during development or as a consequence of learning and memory. Over the much longer evolutionary timescale more fundamental remodeling can take place across species the number of neurons can be significantly modified the gross anatomy can be reorganized and the specializations of particular neurons and neuronal circuits can be substantially altered. Given the fundamental importance of behavior to an organism s survival and reproduction understanding the mechanisms by which evolutionary changes in brain circuitry modify behavior is a major challenge in evolutionary biology. Nematodes offer unique advantages for exploring neuronal remodeling at the evolutionary timescale. They have relatively simple nervous systems typically consisting of around 300 neurons and ample information exists on the phylogenetic relationships among nematode species. In addition a complete connectivity map is