Int. J. Biosci.1( 4), 36-50, August 2011
LTP (Long Term Potentiation) pathway, which is responsible for long-term memory development is defined as the long-lasting enhancement in communication between two neurons that results from stimulating them simultaneously. One of the most important genes concerning this LTP pathway is Raf which actually encodes for KSR1 (kinase suppressor of ras-1) compartmentalizes Hippocampal Signal Transduction and sub serves synaptic plasticity and Memory formation has been explored through the use of comparative genomics in this work. For this purpose, syntenic regions for KSR1 genes in human, chimpanzee, mouse and other organisms are computationally searched to find about the conserved regions and their function through the course of evolution. A coding region was found on chromosome 16 syntenic region for KSR1 of chimpanzee. Sequence comparisons among members of the Raf family reveal the presence of three blocks of conserved sequences: conserved regions (CR) 1, 2, and 3. In this work conserved regions are found in near the C-terminal and N-terminal region was absent in both human and chimpanzee which suggests C terminal region is very important and N –terminal region is dispensable for raf-1 activity which supports the previous finding. Phylogenetic analysis showed that the KSR1 of human and chimpanzee are evolutionary distant from other organisms and human is most closely related with chimpanzee than any other organism which is also supported by previous evolutionary concept.
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